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Ibekpobaoku AN, Oboh MA, Faal F, Adeniji E, Ajibaye O, Idowu ET, Amambua-Ngwa A. Sub-microscopic Plasmodium falciparum infections and multiple drug resistant single nucleotide polymorphic alleles in pregnant women from southwestern Nigeria. BMC Res Notes 2024; 17:129. [PMID: 38725016 PMCID: PMC11083805 DOI: 10.1186/s13104-024-06763-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 04/02/2024] [Indexed: 05/12/2024] Open
Abstract
OBJECTIVES The study evaluated sub-microscopic malaria infections in pregnancy using two malaria Rapid Diagnostic Tests (mRDTs), microscopy and RT-PCR and characterized Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and Plasmodium falciparum dihydropteroate synthase (Pfdhps) drug resistant markers in positive samples. METHODS This was a cross sectional survey of 121 pregnant women. Participants were finger pricked, blood drops were collected for rapid diagnosis with P. falciparum histidine-rich protein 11 rapid diagnostic test kit and the ultra-sensitive Alere Pf malaria RDT, Blood smears for microscopy and dried blood spots on Whatman filter paper for molecular analysis were made. Real time PCR targeting the var acidic terminal sequence (varATS) gene of P. falciparum was carried out on a CFX 96 real time system thermocycler (BioRad) in discriminating malaria infections. For each run, laboratory strain of P. falciparum 3D7 and nuclease free water were used as positive and negative controls respectively. Additionally, High resolution melt analyses was employed for genotyping of the different drug resistance markers. RESULTS Out of one hundred and twenty-one pregnant women sampled, the SD Bioline™ Malaria Ag P.f HRP2-based malaria rapid diagnostic test (mRDT) detected eight (0.06%) cases, the ultra-sensitive Alere™ malaria Ag P.f rapid diagnostic test mRDT had similar outcome in the same samples as detected by the HRP2-based mRDT. Microscopy and RT-PCR confirmed four out of the eight infections detected by both rapid diagnostic tests as true positive and RT-PCR further detected three false negative samples by the two mRDTs providing a sub-microscopic malaria prevalence of 3.3%. Single nucleotide polymorphism in Pfdhps gene associated with sulphadoxine resistance revealed the presence of S613 mutant genotypes in three of the seven positive isolates and isolates with mixed wild/mutant genotype at codon A613S. Furthermore, four mixed genotypes at the A581G codon were also recorded while the other Pfdhps codons (A436G, A437G and K540E) showed the presence of wild type alleles. In the Pfdhfr gene, there were mutations in 28.6%, 28.6%, and 85.7% at the I51, R59 and N108 codons respectively. Mixed wild and mutant type genotypes were also observed in 28.6% each of the N51I, and C59R codons. For the Pfcrt, two haplotypes CVMNK and CVIET were observed. The SVMNT was altogether absent. Triple mutant CVIET 1(14.3%) and triple mutant + wild genotype CVIET + CVMNK 1(14.3%) were observed. The Pfmdr1 haplotypes were single mutants YYND 1(14.3%); NFND 1(14.3%) and double mutants YFND 4(57.1%); YYDD 1(14.3%).
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Affiliation(s)
| | - Mary A Oboh
- Medical Research Council The Gambia Unit (MRC), Banjul, Gambia.
- Rochester Institute of Technology, Rochester, USA.
- University of Medical Sciences, Ondo, Nigeria.
| | - Fatou Faal
- Medical Research Council The Gambia Unit (MRC), Banjul, Gambia
| | | | - Olusola Ajibaye
- Nigerian Institute of Medical Research (NIMR), Yaba, Lagos, Nigeria
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Schreidah C, Giesbrecht D, Gashema P, Young N, Munyaneza T, Muvunyi CM, Thwai K, Mazarati JB, Bailey J, Juliano JJ, Karema C. Expansion of Artemisinin Partial Resistance Mutations and Lack of Histidine Rich Protein-2 and -3 Deletions in Plasmodium falciparum infections from Rukara, Rwanda. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.12.17.23300081. [PMID: 38196592 PMCID: PMC10775326 DOI: 10.1101/2023.12.17.23300081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Background Emerging artemisinin resistance and diagnostic resistance are a threat to malaria control in Africa. Plasmodium falciparum kelch13 (K13) propeller-domain mutations that confer artemisinin partial resistance have emerged in Africa. K13-561H was initially described at a frequency of 7.4% from Masaka in 2014-2015 but not present in nearby Rukara. By 2018, 19.6% of isolates in Masaka and 22% of isolates in Rukara contained the mutation. Longitudinal monitoring is essential to inform control efforts. In Rukara, we sought to assess recent K13-561H prevalence changes, as well as for other key mutations. Prevalence of hrp2/3 deletions was also assessed. Methods We genotyped samples collected in Rukara in 2021 for key artemisinin and partner drug resistance mutations using molecular inversion probe assays and for hrp2/3 deletions using qPCR. Results Clinically validated K13 artemisinin partial resistance mutations continue to increase in prevalence with the overall level of artemisinin resistance mutant infections reaching 32% in Rwanda. The increase appears to be due to the rapid emergence of K13-675V (6.4%, 6/94 infections), previously not observed, rather than continued expansion of 561H (23.5% 20/85). Mutations to partner drugs and other antimalarials were variable, with high levels of multidrug resistance 1 (MDR1) N86 (95.5%) associated with lumefantrine resistance and dihydrofolate reductase (DHFR) 164L (24.7%) associated with antifolate resistance, but low levels of amodiaquine resistance polymorphisms with chloroquine resistance transporter (CRT ) 76T: at 6.1% prevalence. No hrp2 or hrp3 gene deletions associated with diagnostic resistance were found. Conclusions Increasing prevalence of artemisinin partial resistance due to K13-561H and the rapid expansion of K13-675V is concerning for the longevity of artemisinin effectiveness in the region. False negative mRDT results do not appear to be an issue with no hrp2 or hpr3 deletions detected. Continued molecular surveillance in this region and surrounding areas is needed to follow artemisinin resistance and provide early detection of partner drug resistance, which would likely compromise control and increase malaria morbidity and mortality in East Africa.
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Nkemngo FN, Raissa LW, Nguete DN, Ndo C, Fru-Cho J, Njiokou F, Wanji S, Wondji CS. Geographical emergence of sulfadoxine-pyrimethamine drug resistance-associated P. falciparum and P. malariae alleles in co-existing Anopheles mosquito and asymptomatic human populations across Cameroon. Antimicrob Agents Chemother 2023; 67:e0058823. [PMID: 37947766 PMCID: PMC10720508 DOI: 10.1128/aac.00588-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 09/28/2023] [Indexed: 11/12/2023] Open
Abstract
Malaria molecular surveillance remains critical in detecting and tracking emerging parasite resistance to anti-malarial drugs. The current study employed molecular techniques to determine Plasmodium species prevalence and characterize the genetic diversity of Plasmodium falciparum and Plasmodium malariae molecular markers of sulfadoxine-pyrimethamine resistance in humans and wild Anopheles mosquito populations in Cameroon. Anopheles mosquito collections and parasitological survey were conducted in villages to determine Plasmodium species infection, and genomic phenotyping of anti-folate resistance was accomplished by sequencing the dihydrofolate-reductase (dhfr) and dihydropteroate-synthase (dhps) genes of naturally circulating P. falciparum and P. malariae isolates. The malaria prevalence in Elende was 73.5% with the 5-15 years age group harboring significant P. falciparum (27%) and P. falciparum + P. malariae (19%) infections. The polymorphism breadth of the pyrimethamine-associated Pfdhfr marker revealed a near fixation (94%) of the triple-mutant -A16I51R59N108I164. The Pfdhps backbone mediating sulfadoxine resistance reveals a high frequency of the V431A436G437K540A581A613 alleles (20.8%). Similarly, the Pmdhfr N50K55L57R58S59S114F168I170 haplotype (78.4%) was predominantly detected in the asexual blood stage. In contrast, the Pmdhps- S436A437occured at 37.2% frequency. The combined quadruple N50K55L57R58S59S114F168I170_ S436G437K540A581A613 (31.9%) was the major circulating haplotype with similar frequency in humans and mosquitoes. This study highlights the increasing frequency of the P. malariae parasite mostly common in asymptomatic individuals with apparent P. falciparum infection. Interventions directed at reducing malaria transmission such as the scaling-up of SP are favoring the emergence and spread of multiple drug-resistant alleles between the human and mosquito host systems.
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Affiliation(s)
- Francis N. Nkemngo
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Lymen W. Raissa
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
| | - Daniel N. Nguete
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
| | - Cyrille Ndo
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon
| | - Jerome Fru-Cho
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment, Buea, Cameroon
- Centre for Infection Biology and Translational Research, Forzi Institute, Buea, Cameroon
| | - Flobert Njiokou
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
| | - Samuel Wanji
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment, Buea, Cameroon
| | - Charles S. Wondji
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Guémas E, Coppée R, Ménard S, du Manoir M, Nsango S, Makaba Mvumbi D, Nakoune E, Eboumbou Moukoko CE, Bouyou Akotet MK, Mirabeau TY, Manguin S, Malekita Yobi D, Akiana J, Kouna LC, Mawili Mboumba DP, Voumbo-Matoumona DF, Otam AL, Rubbo PA, Lombart JP, Kwanai E, Cohen O, Iriart X, Ayong L, Lekana-Douki JB, Ariey F, Berry A. Evolution and spread of Plasmodium falciparum mutations associated with resistance to sulfadoxine-pyrimethamine in central Africa: a cross-sectional study. THE LANCET. MICROBE 2023; 4:e983-e993. [PMID: 37865113 DOI: 10.1016/s2666-5247(23)00211-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 10/23/2023]
Abstract
BACKGROUND Efficacy of sulfadoxine-pyrimethamine, the malaria chemoprophylaxis used in pregnant women, and in children when combined with amodiaquine, is threatened by the accumulation of mutations in the Plasmodium falciparum dihydropteroate synthase (pfdhps) and dihydrofolate reductase (pfdhfr) genes. Data on the prevalence of resistant alleles in central Africa and the new pfdhps I431V mutation, particularly associated with other mutations to form the pfdhps vagKgs allele, are scarce. We explored the frequency and geographical distribution of pfdhps and pfdhfr mutations in central Africa in 2014-18, and assessed the evolutionary origin of the vagKgs allele. METHODS Samples were collected at 18 health-care centres in seven countries (Angola, Cameroon, Central African Republic, Democratic Republic of the Congo, Gabon, Nigeria, and Republic of the Congo) from patients who showed possible symptoms of malaria between March 1, 2014, and Oct 31, 2018. Samples that were positive for P falciparum were transported to a laboratory in Toulouse, France, and genotyped. The frequency of pfdhfr and pfdhps mutations was studied in 1749 samples. Microsatellites in pfdhps flanking regions and whole-genome analysis compared with parasite genomes from the data-sharing network MalariaGEN were performed on samples carrying the vagKgs allele. FINDINGS Mapping of the prevalence of single nucleotide polymorphisms and corresponding alleles of pfdhfr and pfdhps showed a substantial spread of alleles associated with sulfadoxine-pyrimethamine resistance in central Africa during the 2014-18 period, especially an increase going west to east in pfdhps alleles carrying the K540E and A581G mutations. A high prevalence of the pfdhps I431V mutation was observed in Cameroon (exceeding 50% in the northern region) and Nigeria. Genomic analysis showed a recent African emergence and a clonal expansion of the most frequent pfdhps vagKgs allele. INTERPRETATION Reduced sulfadoxine-pyrimethamine efficacy due to increased resistance is a worrying situation, especially because the malaria transmission level is high in central Africa. Although the resistance phenotype remains to be confirmed, the emergence and spread of the vagKgs allele in west and central Africa could challenge the use of sulfadoxine-pyrimethamine. FUNDING Toulouse Institute for Infectious and Inflammatory Diseases.
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Affiliation(s)
- Emilie Guémas
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France; Département de Parasitologie et Mycologie, CHU Toulouse, Toulouse, France; LAAS-CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Romain Coppée
- Université Paris Cité and Sorbonne Paris Nord, INSERM, IAME, Paris, France
| | - Sandie Ménard
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France
| | - Milena du Manoir
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France
| | - Sandrine Nsango
- Faculté de Médecine et des Sciences Pharmaceutiques, Université de Douala, Douala, Cameroon; Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Dieudonné Makaba Mvumbi
- Department of Basic Sciences, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo; Institute for Medical Immunology, Université Libre de Bruxelles, Brussells, Belgium
| | | | - Carole Else Eboumbou Moukoko
- Faculté de Médecine et des Sciences Pharmaceutiques, Université de Douala, Douala, Cameroon; Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Marielle Karine Bouyou Akotet
- Département de Parasitologie Mycologie Médecine Tropicale, Faculté de Médecine de l'Université des Sciences de la Santé, Libreville, Gabon; Centre de Recherche Biomédicale en Pathogènes Infectieux et Pathologies Associées, CREIPA, Université des Sciences de la Santé, Libreville, Gabon
| | - Tatfeng Youtchou Mirabeau
- Department of Medical Laboratory Science, Faculty of Basic Medical Sciences, College of Health Sciences, Niger Delta University, Wilberforce Island, Nigeria
| | - Sylvie Manguin
- Hydro Sciences Montpellier, Université de Montpellier, CNRS, IRD, Montpellier, France
| | - Doudou Malekita Yobi
- Department of Basic Sciences, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jean Akiana
- Laboratoire National de Santé Publique, Université Marien Ngouabi, Brazzaville, Republic of the Congo
| | - Lady Charlène Kouna
- Unité d'Evolution Epidémiologie et Résistances Parasitaires, Centre Interdisciplinaire de Recherches Médicales de Franceville, Franceville, Gabon; Département de Parasitologie-Mycologie, Université des Sciences de la Santé, Libreville, Gabon
| | - Denise Patricia Mawili Mboumba
- Département de Parasitologie Mycologie Médecine Tropicale, Faculté de Médecine de l'Université des Sciences de la Santé, Libreville, Gabon; Centre de Recherche Biomédicale en Pathogènes Infectieux et Pathologies Associées, CREIPA, Université des Sciences de la Santé, Libreville, Gabon
| | - Dominique Fatima Voumbo-Matoumona
- Laboratoire National de Santé Publique, Université Marien Ngouabi, Brazzaville, Republic of the Congo; Unité d'Evolution Epidémiologie et Résistances Parasitaires, Centre Interdisciplinaire de Recherches Médicales de Franceville, Franceville, Gabon; Département de Parasitologie-Mycologie, Université des Sciences de la Santé, Libreville, Gabon
| | - Alliance-Laure Otam
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France
| | | | | | - Elisabeth Kwanai
- Coordination diocésaine de la Santé, Diocèse de Maroua-Mokolo, Maroua, Cameroon
| | - Olivia Cohen
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France
| | - Xavier Iriart
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France; Département de Parasitologie et Mycologie, CHU Toulouse, Toulouse, France
| | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Jean Bernard Lekana-Douki
- Unité d'Evolution Epidémiologie et Résistances Parasitaires, Centre Interdisciplinaire de Recherches Médicales de Franceville, Franceville, Gabon; Département de Parasitologie-Mycologie, Université des Sciences de la Santé, Libreville, Gabon
| | - Frédéric Ariey
- INSERM U1016, Institut Cochin, Laboratoire de Parasitologie-Mycologie, Hôpital Cochin, AP-HP, Université Paris Cité, Paris, France
| | - Antoine Berry
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université de Toulouse, CNRS UMR5051, INSERM UMR 1291, UPS, Toulouse, France; Département de Parasitologie et Mycologie, CHU Toulouse, Toulouse, France.
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Tarama CW, Soré H, Siribié M, Débé S, Kinda R, Ganou A, Nonkani WG, Tiendrebeogo F, Bantango W, Yira K, Sagnon A, Ilboudo S, Hien EY, Guelbéogo MW, Sagnon NF, Traoré Y, Ménard D, Gansané A. Plasmodium falciparum drug resistance-associated mutations in isolates from children living in endemic areas of Burkina Faso. Malar J 2023; 22:213. [PMID: 37474966 PMCID: PMC10360335 DOI: 10.1186/s12936-023-04645-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/11/2023] [Indexed: 07/22/2023] Open
Abstract
BACKGROUND Artemisinin-based combinations therapy (ACT) is the current frontline curative therapy for uncomplicated malaria in Burkina Faso. Sulfadoxine-pyrimethamine (SP) is used for the preventive treatment of pregnant women (IPTp), while SP plus amodiaquine (SP-AQ) is recommended for children under five in seasonal malaria chemoprevention (SMC). This study aimed to assess the proportions of mutations in the P. falciparum multidrug-resistance 1 (Pfmdr1), P. falciparum chloroquine resistance transporter (Pfcrt), P. falciparum dihydrofolate reductase (pfdhfr), and P. falciparum dihydropteroate synthase (pfdhps), genes from isolates collected during household surveys in Burkina Faso. METHODS Dried blood spots from Plasmodium falciparum-positive cases at three sites (Orodara, Gaoua, and Banfora) collected during the peak of transmission were analysed for mutations in Pfcrt (codons 72-76, 93, 97, 145, 218, 343, 350 and 353), Pfmdr-1 (codons 86, 184, 1034, 1042 and 1246) dhfr (codons 51, 59, 108, 164) and dhps (at codons 431, 436, 437, 540, 581, 613) genes using deep sequencing of multiplexed Polymerase chaine reaction (PCR) amplicons. RESULTS Of the 377 samples analysed, 346 (91.7%), 369 (97.9%), 368 (97.6%), and 374 (99.2%) were successfully sequenced for Pfcrt, Pfmdr-1, dhfr, and dhps, respectively. Most of the samples had a Pfcrt wild-type allele (89.3%). The 76T mutation was below 10%. The most frequent Pfmdr-1 mutation was detected at codon 184 (Y > F, 30.9%). The single mutant genotype (NFSND) predominated (66.7%), followed by the wild-type genotype (NYSND, 30.4%). The highest dhfr mutations were observed at codon 59R (69.8%), followed by codons 51I (66.6%) and 108 N (14.7%). The double mutant genotype (ACIRSI) predominated (52.4%). For mutation in the dhps gene, the highest frequency was observed at codon 437 K (89.3%), followed by codons 436 A (61.2%), and 613 S (14.4%). The double mutant genotype (IAKKAA) and the single mutant genotype (ISKKAA) were predominant (37.7% and 37.2%, respectively). The most frequent dhfr/dhps haplotypes were the triple mutant ACIRSI/IAKKAA (23%), the wild-type ACNCSI/ISKKAA (19%) and the double mutant ACIRSI/ISKKAA (14%). A septuple mutant ACIRNI/VAKKGA was observed in 2 isolates from Gaoua (0.5%). CONCLUSION The efficacy of ACT partner drugs and drugs used in IPTp and SMC does not appear to be affected by the low proportion of highly resistant mutants observed in this study. Continued monitoring, including molecular surveillance, is critical for decision-making on effective treatment policy in Burkina Faso.
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Affiliation(s)
| | - Harouna Soré
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Mafama Siribié
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Siaka Débé
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Réné Kinda
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Adama Ganou
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Wendyam Gérard Nonkani
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Farida Tiendrebeogo
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Winnie Bantango
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Kassoum Yira
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Aladari Sagnon
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Sonia Ilboudo
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | | | | | - NFale Sagnon
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso
| | - Yves Traoré
- Université Joseph KI-ZERBO, Ouagadougou, Burkina Faso
| | - Didier Ménard
- Malaria Genetic and Resistance Unit, Institut Pasteur, Université Paris Cité, INSERM U1201, 75015, Paris, France
- Malaria Parasite Biology and Vaccines, Institut Pasteur, Université Paris Cité, 75015, Paris, France
- Institute of Parasitology and Tropical Diseases, Université de Strasbourg, UR7292 Dynamics of Host-Pathogen Interactions, 67000, Strasbourg, France
- Laboratory of Parasitology and Medical Mycology, CHU Strasbourg, 67000, Strasbourg, France
| | - Adama Gansané
- Centre National de Recherche et de Formation sur le paludisme, Ouagadougou, Burkina Faso.
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Okoro RN, Geidam AD, Bukar AA, Zarami AB, Ohieku JD, Musa AB, Yerima TS. Superiority trial of intermittent treatment with dihydroartemisinin–piperaquine versus sulfadoxine–pyrimethamine for the prevention of malaria during pregnancy. FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2023. [DOI: 10.1186/s43094-023-00460-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Abstract
Background
Malaria in pregnancy is responsible for various adverse maternal and birth outcomes. The emerging resistance to sulfadoxine–pyrimethamine (SP) raises important concerns about its use for intermittent preventive treatment in pregnancy (IPTp) in Africa. This trial aimed to assess the efficacy and safety of IPTp with dihydroartemisinin–piperaquine (DP) as an alternative to IPTp with SP.
Results
The double-blind, randomized, and controlled superiority trial was conducted between July 2020 and June 2021. A total of 250 women were enrolled and randomly assigned to receive SP (n = 125) or DP (n = 125). Two hundred and six (82.4%) participants that contributed to the outcomes were included in the modified intention-to-treat (ITT) analysis, while 84 participants that completed the three courses of the study drugs were included in the per protocol (PP) analysis. The ITT analysis results showed that the incidence of histopathologically confirmed placental malaria was nonsignificantly higher in the DP group compared with the SP group (62.5% vs. 51.1%, P = 0.098). After adjusting for confounders, the risk of histopathologically confirmed placental malaria was also nonsignificantly higher in the DP group (Adjusted Relative Risk [RR] = 1.27, 95% CI 0.94–1.71) compared with the SP group. In contrast, the risk of a low APGAR score was significantly lower in the DP group (RR = 0.45, 95% CI 0.38–0.52) compared with the SP group. Also, the risk of a composite adverse birth outcome (low birth weight or preterm delivery or neonates small for the gestational age) was nonsignificantly lower in the DP group (Adjusted RR = 0.82, 95% CI 0.55–1.21) compared with the SP group. Both drugs were well tolerated, although nausea and vomiting occurred in a significant number of participants in the SP group.
Conclusions
A three-course IPTp with DP was safe and was not found to be superior to IPTp with SP in the prevention of placental malaria. Although IPTp with DP was associated with a significant lower risk of low APGAR score and nonsignificant lower risks of other adverse birth outcomes compared with IPTp with SP.
Trial registration
PACTR, PACTR202002644579177. Registered 20 February 2020, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9753.
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Spatiotemporal spread of Plasmodium falciparum mutations for resistance to sulfadoxine-pyrimethamine across Africa, 1990–2020. PLoS Comput Biol 2022; 18:e1010317. [PMID: 35951528 PMCID: PMC9371298 DOI: 10.1371/journal.pcbi.1010317] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 06/19/2022] [Indexed: 11/26/2022] Open
Abstract
Background Sulfadoxine-pyrimethamine (SP) is recommended in Africa in several antimalarial preventive regimens including Intermittent Preventive Treatment in pregnant women (IPTp), Intermittent Preventive Treatment in infants (IPTi) and Seasonal Malaria Chemoprevention (SMC). The effectiveness of SP-based preventive treatments are threatened in areas where Plasmodium falciparum resistance to SP is high. The prevalence of mutations in the dihydropteroate synthase gene (pfdhps) can be used to monitor SP effectiveness. IPTi-SP is recommended only in areas where the prevalence of the pfdhps540E mutation is below 50%. It has also been suggested that IPTp-SP does not have a protective effect in areas where the pfdhps581G mutation, exceeds 10%. However, pfdhps mutation prevalence data in Africa are extremely heterogenous and scattered, with data completely missing from many areas. Methods and findings The WWARN SP Molecular Surveyor database was designed to summarize dihydrofolate reductase (pfdhfr) and pfdhps gene mutation prevalence data. In this paper, pfdhps mutation prevalence data was used to generate continuous spatiotemporal surface maps of the estimated prevalence of the SP resistance markers pfdhps437G, pfdhps540E, and pfdhps581G in Africa from 1990 to 2020 using a geostatistical model, with a Bayesian inference framework to estimate uncertainty. The maps of estimated prevalence show an expansion of the pfdhps437G mutations across the entire continent over the last three decades. The pfdhps540E mutation emerged from limited foci in East Africa to currently exceeding 50% estimated prevalence in most of East and South East Africa. pfdhps540E distribution is expanding at low or moderate prevalence in central Africa and a predicted focus in West Africa. Although the pfdhps581G mutation spread from one focus in East Africa in 2000, to exceeding 10% estimated prevalence in several foci in 2010, the predicted distribution of the marker did not expand in 2020, however our analysis indicated high uncertainty in areas where pfdhps581G is present. Uncertainty was higher in spatial regions where the prevalence of a marker is intermediate or where prevalence is changing over time. Conclusions The WWARN SP Molecular Surveyor database and a set of continuous spatiotemporal surface maps were built to provide users with standardized, current information on resistance marker distribution and prevalence estimates. According to the maps, the high prevalence of pfdhps540E mutation was to date restricted to East and South East Africa, which is reassuring for continued use of IPTi and SMC in West Africa, but continuous monitoring is needed as the pfdhps540E distribution is expanding. Several foci where pfdhps581G prevalence exceeded 10% were identified. More data on the pfdhps581G distribution in these areas needs to be collected to guide IPTp-SP recommendations. Prevalence and uncertainty maps can be utilized together to strategically identify sites where increased surveillance can be most informative. This study combines a molecular marker database and predictive modelling to highlight areas of concern, which can be used to support decisions in public health, highlight knowledge gaps in certain regions, and guide future research. Despite great success in reducing death and illness from malaria over the last 20 years, the disease is still one of the main leading causes of death in low-income countries with estimated 229 million cases and 409,000 deaths annually. One of the main obstacles in malaria control is the development and spread of drug resistance. Several intermittent preventive treatments depend on the efficacy of the antimalarial drug sulfadoxine-pyrimethamine (SP); Intermittent Preventive Treatment in pregnant women (IPTp), Intermittent Preventive Treatment in infants (IPTi) and Seasonal Malaria Chemoprevention (SMC). Mutations in the dihydropteroate synthase gene (pfdhps) can cause resistance to SP treatment. In this paper, we use pfdhps mutation prevalence data to generate continuous spatiotemporal surface maps of the estimated prevalence of the SP resistance markers in Africa from 1990 to 2020 using a Bayesian geostatistical model. These predictive maps provide much needed insight about where SP can be used as part of preventive treatments. Spatial information on the spread of antimalarial resistance is critical for health organizations to prioritize surveillance measures, and plan control and elimination efforts.
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Issa I, Lamine MM, Hubert V, Ilagouma A, Adehossi E, Mahamadou A, Lobo NF, Sarr D, Shollenberger LM, Sandrine H, Jambou R, Laminou IM. Prevalence of Mutations in the Pfdhfr, Pfdhps, and Pfmdr1 Genes of Malarial Parasites Isolated from Symptomatic Patients in Dogondoutchi, Niger. Trop Med Infect Dis 2022; 7:tropicalmed7080155. [PMID: 36006247 PMCID: PMC9413624 DOI: 10.3390/tropicalmed7080155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 11/16/2022] Open
Abstract
The effectiveness of artemisinin-based combination therapies (ACTs) depends not only on that of artemisinin but also on that of partner molecules. This study aims to evaluate the prevalence of mutations in the Pfdhfr, Pfdhps, and Pfmdr1 genes from isolates collected during a clinical study. Plasmodium genomic DNA samples extracted from symptomatic malaria patients from Dogondoutchi, Niger, were sequenced by the Sanger method to determine mutations in the Pfdhfr (codons 51, 59, 108, and 164), Pfdhps (codons 436, 437, 540, 581, and 613), and Pfmdr1 (codons 86, 184, 1034, and 1246) genes. One hundred fifty-five (155) pre-treatment samples were sequenced for the Pfdhfr, Pfdhps, and Pfmdr1 genes. A high prevalence of mutations in the Pfdhfr gene was observed at the level of the N51I (84.97%), C59R (92.62%), and S108N (97.39%) codons. The key K540E mutation in the Pfdhps gene was not observed. Only one isolate was found to harbor a mutation at codon I431V. The most common mutation on the Pfmdr1 gene was Y184F in 71.43% of the mutations found, followed by N86Y in 10.20%. The triple-mutant haplotype N51I/C59R/S108N (IRN) was detected in 97% of the samples. Single-mutant (ICS and NCN) and double-mutant (IRS, NRN, and ICN) haplotypes were prevalent at 97% and 95%, respectively. Double-mutant haplotypes of the Pfdhps (581 and 613) and Pfmdr (86 and 184) were found in 3% and 25.45% of the isolates studied, respectively. The study focused on the molecular analysis of the sequencing of the Pfdhfr, Pfdhps, and Pfmdr1 genes. Although a high prevalence of mutations in the Pfdhfr gene have been observed, there is a lack of sulfadoxine pyrimethamine resistance. There is a high prevalence of mutation in the Pfmdr184 codon associated with resistance to amodiaquine. These data will be used by Niger’s National Malaria Control Program to better monitor the resistance of Plasmodium to partner molecules in artemisinin-based combination therapies.
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Affiliation(s)
- Ibrahima Issa
- Centre de Recherche Médicale et Sanitaire, Niamey P.O. Box 10887, Niger; (I.I.); (A.M.); (R.J.)
| | | | - Veronique Hubert
- Centre National de Référence du Paludisme à Paris en France, 75013 Paris, France; (V.H.); (H.S.)
| | - Amadou Ilagouma
- Faculty of Sciences, University Abdou Moumouni of Niamey, Niamey P.O. Box 10662, Niger; (A.I.); (E.A.)
| | - Eric Adehossi
- Faculty of Sciences, University Abdou Moumouni of Niamey, Niamey P.O. Box 10662, Niger; (A.I.); (E.A.)
| | - Aboubacar Mahamadou
- Centre de Recherche Médicale et Sanitaire, Niamey P.O. Box 10887, Niger; (I.I.); (A.M.); (R.J.)
| | - Neil F. Lobo
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA;
| | - Demba Sarr
- Department of Infectious Diseases, University of Georgia, Athens, GA 30602, USA;
| | | | - Houze Sandrine
- Centre National de Référence du Paludisme à Paris en France, 75013 Paris, France; (V.H.); (H.S.)
| | - Ronan Jambou
- Centre de Recherche Médicale et Sanitaire, Niamey P.O. Box 10887, Niger; (I.I.); (A.M.); (R.J.)
| | - Ibrahim Maman Laminou
- Centre de Recherche Médicale et Sanitaire, Niamey P.O. Box 10887, Niger; (I.I.); (A.M.); (R.J.)
- Correspondence: ; Tel.: +227-80-88-20-22
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Plowe CV. Malaria chemoprevention and drug resistance: a review of the literature and policy implications. Malar J 2022; 21:104. [PMID: 35331231 PMCID: PMC8943514 DOI: 10.1186/s12936-022-04115-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/03/2022] [Indexed: 01/19/2023] Open
Abstract
Chemoprevention strategies reduce malaria disease and death, but the efficacy of anti-malarial drugs used for chemoprevention is perennially threatened by drug resistance. This review examines the current impact of chemoprevention on the emergence and spread of drug resistant malaria, and the impact of drug resistance on the efficacy of each of the chemoprevention strategies currently recommended by the World Health Organization, namely, intermittent preventive treatment in pregnancy (IPTp); intermittent preventive treatment in infants (IPTi); seasonal malaria chemoprevention (SMC); and mass drug administration (MDA) for the reduction of disease burden in emergency situations. While the use of drugs to prevent malaria often results in increased prevalence of genetic mutations associated with resistance, malaria chemoprevention interventions do not inevitably lead to meaningful increases in resistance, and even high rates of resistance do not necessarily impair chemoprevention efficacy. At the same time, it can reasonably be anticipated that, over time, as drugs are widely used, resistance will generally increase and efficacy will eventually be lost. Decisions about whether, where and when chemoprevention strategies should be deployed or changed will continue to need to be made on the basis of imperfect evidence, but practical considerations such as prevalence patterns of resistance markers can help guide policy recommendations.
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Targeted Amplicon Deep Sequencing for Monitoring Antimalarial Resistance Markers in Western Kenya. Antimicrob Agents Chemother 2022; 66:e0194521. [PMID: 35266823 PMCID: PMC9017353 DOI: 10.1128/aac.01945-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Molecular surveillance of Plasmodium falciparum parasites is important to track emerging and new mutations and trends in established mutations and should serve as an early warning system for antimalarial resistance. Dried blood spots were obtained from a Plasmodium falciparum malaria survey in school children conducted across eight counties in western Kenya in 2019. Real-time PCR identified 500 P. falciparum-positive samples that were amplified at five drug resistance loci for targeted amplicon deep sequencing (TADS). The absence of important kelch 13 mutations was similar to previous findings in Kenya pre-2019, and low-frequency mutations were observed in codons 569 and 578. The chloroquine resistance transporter gene codons 76 and 145 were wild type, indicating that the parasites were chloroquine and piperaquine sensitive, respectively. The multidrug resistance gene 1 haplotypes based on codons 86, 184, and 199 were predominantly present in mixed infections with haplotypes NYT and NFT, driven by the absence of chloroquine pressure and the use of lumefantrine, respectively. The sulfadoxine-pyrimethamine resistance profile was a “superresistant” combination of triple mutations in both Pfdhfr (51I 59R 108N) and Pfdhps (436H 437G 540E), rendering sulfadoxine-pyrimethamine ineffective. TADS highlighted the low-frequency variants, allowing the early identification of new mutations, Pfmdr1 codon 199S and Pfdhfr codon 85I and emerging 164L mutations. The added value of TADS is its accuracy in identifying mixed-genotype infections and for high-throughput monitoring of antimalarial resistance markers.
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11
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Roux AT, Maharaj L, Oyegoke O, Akoniyon OP, Adeleke MA, Maharaj R, Okpeku M. Chloroquine and Sulfadoxine-Pyrimethamine Resistance in Sub-Saharan Africa-A Review. Front Genet 2021; 12:668574. [PMID: 34249090 PMCID: PMC8267899 DOI: 10.3389/fgene.2021.668574] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/20/2021] [Indexed: 12/20/2022] Open
Abstract
Malaria is a great concern for global health and accounts for a large amount of morbidity and mortality, particularly in Africa, with sub-Saharan Africa carrying the greatest burden of the disease. Malaria control tools such as insecticide-treated bed nets, indoor residual spraying, and antimalarial drugs have been relatively successful in reducing the burden of malaria; however, sub-Saharan African countries encounter great challenges, the greatest being antimalarial drug resistance. Chloroquine (CQ) was the first-line drug in the 20th century until it was replaced by sulfadoxine-pyrimethamine (SP) as a consequence of resistance. The extensive use of these antimalarials intensified the spread of resistance throughout sub-Saharan Africa, thus resulting in a loss of efficacy for the treatment of malaria. SP was replaced by artemisinin-based combination therapy (ACT) after the emergence of resistance toward SP; however, the use of ACTs is now threatened by the emergence of resistant parasites. The decreased selective pressure on CQ and SP allowed for the reintroduction of sensitivity toward those antimalarials in regions of sub-Saharan Africa where they were not the primary drug for treatment. Therefore, the emergence and spread of antimalarial drug resistance should be tracked to prevent further spread of the resistant parasites, and the re-emergence of sensitivity should be monitored to detect the possible reappearance of sensitivity in sub-Saharan Africa.
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Affiliation(s)
- Alexandra T. Roux
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, South Africa
| | - Leah Maharaj
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, South Africa
| | - Olukunle Oyegoke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, South Africa
| | - Oluwasegun P. Akoniyon
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, South Africa
| | - Matthew Adekunle Adeleke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, South Africa
| | - Rajendra Maharaj
- Office of Malaria Research, South African Medical Research Council, Cape Town, South Africa
| | - Moses Okpeku
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, South Africa
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Ndwiga L, Kimenyi KM, Wamae K, Osoti V, Akinyi M, Omedo I, Ishengoma DS, Duah-Quashie N, Andagalu B, Ghansah A, Amambua-Ngwa A, Tukwasibwe S, Tessema SK, Karema C, Djimde AA, Dondorp AM, Raman J, Snow RW, Bejon P, Ochola-Oyier LI. A review of the frequencies of Plasmodium falciparum Kelch 13 artemisinin resistance mutations in Africa. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2021; 16:155-161. [PMID: 34146993 PMCID: PMC8219943 DOI: 10.1016/j.ijpddr.2021.06.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/28/2021] [Accepted: 06/07/2021] [Indexed: 12/23/2022]
Abstract
Artemisinin resistance (AR) emerged in South East Asia 13 years ago and the identification of the resistance conferring molecular marker, Plasmodium falciparum Kelch 13 (Pfk13), 7 years ago has provided an invaluable tool for monitoring AR in malaria endemic countries. Molecular Pfk13 surveillance revealed the resistance foci in the Greater Mekong Subregion, an independent emergence in Guyana, South America, and a low frequency of mutations in Africa. The recent identification of the R561H Pfk13 AR associated mutation in Tanzania, Uganda and in Rwanda, where it has been associated with delayed parasite clearance, should be a concern for the continent. In this review, we provide a summary of Pfk13 resistance associated propeller domain mutation frequencies across Africa from 2012 to 2020, to examine how many other countries have identified these mutations. Only four African countries reported a recent identification of the M476I, P553L, R561H, P574L, C580Y and A675V Pfk13 mutations at low frequencies and with no reports of clinical treatment failure, except for Rwanda. These mutations present a threat to malaria control across the continent, since the greatest burden of malaria remains in Africa. A rise in the frequency of these mutations and their spread would reverse the gains made in the reduction of malaria over the last 20 years, given the lack of new antimalarial treatments in the event artemisinin-based combination therapies fail. The review highlights the frequency of Pfk13 propeller domain mutations across Africa, providing an up-to-date perspective of Pfk13 mutations, and appeals for an urgent and concerted effort to monitoring antimalarial resistance markers in Africa and the efficacy of antimalarials by re-establishing sentinel surveillance systems.
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Affiliation(s)
- Leonard Ndwiga
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya
| | - Kelvin M Kimenyi
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Centre for Biotechnology and Bioinformatics, University of Nairobi, Nairobi, Kenya
| | - Kevin Wamae
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya
| | - Victor Osoti
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya
| | - Mercy Akinyi
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya
| | - Irene Omedo
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Big Data Institute at the Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, United Kingdom
| | - Deus S Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania
| | - Nancy Duah-Quashie
- Department of Epidemiology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | - Anita Ghansah
- Department of Parasitology, Noguchi Memorial Institute for Medical Research (NMIMR), Accra, Ghana
| | | | | | | | - Corine Karema
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; Quality and Equity Healthcare, Kigali, Rwanda
| | - Abdoulaye A Djimde
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Arjen M Dondorp
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom; Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Jaishree Raman
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Disease, Sandringham, Gauteng, South Africa; Wits Research Institute for Malaria, Univerisity of Witwatersrand, Johannesburg, South Africa
| | - Robert W Snow
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Philip Bejon
- KEMRI-Wellcome Trust Collaborative Programme, P.O. Box 230, 80108, Kilifi, Kenya; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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Yimam Y, Nateghpour M, Mohebali M, Abbaszadeh Afshar MJ. A systematic review and meta-analysis of asymptomatic malaria infection in pregnant women in Sub-Saharan Africa: A challenge for malaria elimination efforts. PLoS One 2021; 16:e0248245. [PMID: 33793584 PMCID: PMC8016273 DOI: 10.1371/journal.pone.0248245] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 02/23/2021] [Indexed: 11/17/2022] Open
Abstract
Background In Sub-Saharan Africa (SSA), where malaria transmission is stable, malaria infection in pregnancy adversely affects pregnant women, fetuses, and newborns and is often asymptomatic. So far, a plethora of primary studies have been carried out on asymptomatic malaria infection in pregnant women in SSA. Nevertheless, no meta-analysis estimated the burden of asymptomatic malaria infection in pregnant women in SSA, so this meta-analysis was carried out to bridge this gap. Methods PubMed, Web of Science, Scopus, Embase, and ProQuest were systematically searched for relevant studies published until 4 August 2020, and also the expansion of the search was performed by October 24, 2020. We assessed heterogeneity among included studies using I-squared statistics (I2). Publication bias was assessed by visual inspection of the funnel plot and further quantitatively validated by Egger’s and Begg’s tests. The pooled prevalence and pooled odds ratio (OR) and their corresponding 95% Confidence Interval (CI) were estimated using the random-effects model in Stata 15 software. Results For this meta-analysis, we included 35 eligible studies. The overall prevalence estimate of asymptomatic Plasmodium infection prevalence was 26.1%% (95%CI: 21–31.2%, I2 = 99.0%). According to species-specific pooled prevalence estimate, Plasmodium falciparum was dominant species (22.1%, 95%CI: 17.1–27.2%, I2 = 98.6%), followed by Plasmodium vivax, Plasmodium malariae and Plasmodium ovale, respectively, found to be 3% (95%CI: 0–5%, I2 = 88.3%), 0.8% (95%CI: 0.3–0.13%, I2 = 60.5%), and 0.2% (95%CI: -0.01–0.5%, I2 = 31.5%). Asymptomatic malaria-infected pregnant women were 2.28 times more likely anemic (OR = 2.28, 95%CI: 1.66–3.13, I2 = 56.3%) than in non-infected pregnant women. Asymptomatic malaria infection was 1.54 times higher (OR = 1.54, 95%CI: 1.28–1.85, I2 = 11.5%) in primigravida women compared to multigravida women. Conclusion In SSA, asymptomatic malaria infection in pregnant women is prevalent, and it is associated with an increased likelihood of anemia compared to non-infected pregnant women. Thus, screening of asymptomatic pregnant women for malaria and anemia should be included as part of antenatal care.
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Affiliation(s)
- Yonas Yimam
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Department of Biology, Faculty of Natural and Computational Sciences, Woldia University, Woldia, Ethiopia
| | - Mehdi Nateghpour
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Mohebali
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Centers for Research of Endemic Parasites of Iran (CREPI), Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Javad Abbaszadeh Afshar
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Department of Medical Parasitology and Mycology, School of Medicine, Jiroft University of Medical Sciences, Jiroft, Iran
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Amenga-Etego LN, Asoala V, Agongo G, Jacob C, Goncalves S, Awandare GA, Rockett KA, Kwiatkowski D. Temporal evolution of sulfadoxine-pyrimethamine resistance genotypes and genetic diversity in response to a decade of increased interventions against Plasmodium falciparum in northern Ghana. Malar J 2021; 20:152. [PMID: 33731134 PMCID: PMC7968364 DOI: 10.1186/s12936-021-03693-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/06/2021] [Indexed: 11/26/2022] Open
Abstract
Background Anti-malarial drug resistance remains a key concern for the global fight against malaria. In Ghana sulfadoxine-pyrimethamine (SP) is used for intermittent preventive treatment of malaria in pregnancy and combined with amodiaquine for Seasonal Malaria Chemoprevention (SMC) during the high malaria season. Thus, surveillance of molecular markers of SP resistance is important to guide decision-making for these interventions in Ghana. Methods A total of 4469 samples from uncomplicated malaria patients collected from 2009 to 2018 was submitted to the Wellcome Trust Sanger Institute, UK for DNA sequencing using MiSeq. Genotypes were successfully translated into haplotypes in 2694 and 846 mono infections respectively for pfdhfr and pfdhps genes and the combined pfhdfr/pfdhps genes across all years. Results At the pfdhfr locus, a consistently high (> 60%) prevalence of parasites carrying triple mutants (IRNI) were detected from 2009 to 2018. Two double mutant haplotypes (NRNI and ICNI) were found, with haplotype NRNI having a much higher prevalence (average 13.8%) than ICNI (average 3.2%) across all years. Six pfdhps haplotypes were detected. Of these, prevalence of five fluctuated in a downward trend over time from 2009 to 2018, except a pfdhps double mutant (AGKAA), which increased consistently from 2.5% in 2009 to 78.2% in 2018. Across both genes, pfdhfr/pfdhps combined triple (NRNI + AAKAA) mutants were only detected in 2009, 2014, 2015 and 2018, prevalence of which fluctuated between 3.5 and 5.5%. The combined quadruple (IRNI + AAKAA) genotype increased in prevalence from 19.3% in 2009 to 87.5% in 2011 before fluctuating downwards to 19.6% in 2018 with an average prevalence of 37.4% within the nine years. Prevalence of parasites carrying the quintuple (IRNI + AGKAA or SGEAA) mutant haplotypes, which are highly refractory to SP increased over time from 14.0% in 2009 to 89.0% in 2016 before decreasing to 78.9 and 76.6% in 2017 and 2018 respectively. Though quintuple mutants are rising in prevalence in both malaria seasons, together these combined genotypes vary significantly within season but not between seasons. Conclusions Despite high prevalence of pfdhfr triple mutants and combined pfdhfr/pfdhps quadruple and quintuple mutants in this setting SP may still be efficacious. These findings are significant as they highlight the need to continuously monitor SP resistance, particularly using deep targeted sequencing to ascertain changing resistance patterns. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03693-3.
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Affiliation(s)
- Lucas N Amenga-Etego
- West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.
| | - Victor Asoala
- Navrongo Health Research Centre, Ghana Health Service, P. O. Box 114, Navrongo, Ghana
| | - Godfred Agongo
- Navrongo Health Research Centre, Ghana Health Service, P. O. Box 114, Navrongo, Ghana
| | - Christopher Jacob
- Wellcome Centre for Human Genetics, University of Oxford, Headington, Oxford, OX3 7BN, UK
| | - Sonia Goncalves
- Wellcome Centre for Human Genetics, University of Oxford, Headington, Oxford, OX3 7BN, UK
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Kirk A Rockett
- Wellcome Centre for Human Genetics, University of Oxford, Headington, Oxford, OX3 7BN, UK.,Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Dominic Kwiatkowski
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK.,Big Data Institute, University of Oxford, Oxford, UK
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Evidence that seasonal malaria chemoprevention with SPAQ influences blood and pre-erythrocytic stage antibody responses of Plasmodium falciparum infections in Niger. Malar J 2021; 20:1. [PMID: 33386070 PMCID: PMC7775624 DOI: 10.1186/s12936-020-03550-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 12/12/2020] [Indexed: 11/17/2022] Open
Abstract
Background In endemic areas, children develop slowly and naturally anti-Plasmodium antibodies and become semi-immune. Seasonal Malaria Chemoprevention (SMC) with sulfadoxine-pyrimethamine + amodiaquine (SPAQ) is a new strategy to reduce malaria morbidity in West African young children. However, SMC may impact on the natural acquisition of anti-Plasmodium immunity. This paper evaluates the effect of SMC with SPAQ on antibody concentration in young children from Niger. Methods This research was conducted in areas benefitting from SMC since 2014 (Zinder district), without SMC (Dosso district), and with 1 year of SMC since 2016 (Gaya district). To assess the relationship between SMC and Plasmodium falciparum IgG antibody responses, the total antibody concentrations against two P. falciparum asexual stage vaccine candidate antigens, circumsporozoite protein (CSP) and glutamate-rich protein R2 (GLURP-R2), in children aged 3 to 59 months across the three areas were compared. Antibody concentrations are quantified using an enzyme-linked immunosorbent assay on the elution extracted from positive and negative malaria Rapid Diagnostic Test cassettes. Results The analysis concerns two hundred and twenty-nine children aged from 3 to 59 months: 71 in Zinder, 77 in Dosso, and 81 in Gaya. In Zinder (CSP = 17.5 µg/ml and GLURP-R2 = 14.3 µg/ml) median antibody concentration observed are higher than in Gaya (CSP = 7.7 µg/ml and GLURP-R2 = 6.5 µg/ml) and Dosso (CSP = 4.5 µg/ml and GLURP-R2 = 3.6 µg/ml) (p < 0.0001). Conclusion The research reveals some evidences which show that seasonal malaria chemoprevention with SPAQ has an effect on blood stage antibody responses and pre-erythrocytic stage of P. falciparum infections in Niger. Increased antibody titres with increased SMC/SPAQ implementation. This contradicts hypothesis that SMC/SPAQ could reduce immunity to erythrocyte and liver-stage antigens. Further studies are necessary to provide better understanding of the SMC effect on malaria immunity.
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Jiang T, Cheng W, Yao Y, Tan H, Wu K, Li J. Molecular surveillance of anti-malarial resistance Pfdhfr and Pfdhps polymorphisms in African and Southeast Asia Plasmodium falciparum imported parasites to Wuhan, China. Malar J 2020; 19:434. [PMID: 33238987 PMCID: PMC7691106 DOI: 10.1186/s12936-020-03509-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 11/19/2020] [Indexed: 01/02/2023] Open
Abstract
Background Anti-malarial drug resistance is a severe challenge for eventual control and global elimination of malaria. Resistance to sulfadoxine-pyrimethamine (SP) increases as mutations accumulate in the Pfdhfr and Pfdhps genes. This study aimed to assess the polymorphisms and prevalence of mutation in these genes in the Plasmodium falciparum infecting migrant workers returning to Wuhan, China. Methods Blood samples were collected for 9 years (2011–2019). Parasite genomic DNA was extracted from blood spots on filter paper. The mutations were evaluated by nested PCR and sequencing. The single-nucleotide polymorphisms (SNPs) and haplotypes of the Pfdhfr and Pfdhps genes were analysed. Results Pfdhfr codon 108 showed a 94.7% mutation rate, while for Pfdhps, the rate for codon 437 was 79.0%. In total, five unique haplotypes at the Pfdhfr locus and 11 haplotypes at the Pfdhps locus were found while the Pfdhfr-Pfdhps combined loci revealed 28 unique haplotypes. A triple mutant (IRNI) of Pfdhfr was the most prevalent haplotype (84.4%). For Pfdhps, a single mutant (SGKAA) and a double mutant (SGEAA) were detected at frequencies of 37.8 and 22.3%, respectively. Among the combined haplotypes, a quadruple mutant (IRNI-SGKAA) was the most common, with a 30.0% frequency, followed by a quintuplet mutant (IRNI-SGEAA) with a frequency of 20.4%. Conclusion The high prevalence and saturation of Pfdhfr haplotypes and the medium prevalence of Pfdhps haplotypes demonstrated in the present data will provide support for predicting the status and progression of antifolate resistance in malaria-endemic regions and imported malaria in nonendemic areas. Additional interventions to evaluate and prevent SP resistance should be continuously considered.
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Affiliation(s)
- Tingting Jiang
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, China
| | - Weijia Cheng
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, China
| | - Yi Yao
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, China
| | - Huabing Tan
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, China
| | - Kai Wu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, China.
| | - Jian Li
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, China. .,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, China.
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Piperaquine Exposure Is Altered by Pregnancy, HIV, and Nutritional Status in Ugandan Women. Antimicrob Agents Chemother 2020; 64:AAC.01013-20. [PMID: 33020153 DOI: 10.1128/aac.01013-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 09/29/2020] [Indexed: 11/20/2022] Open
Abstract
Dihydroartemisinin-piperaquine (DHA-PQ) provides highly effective therapy and chemoprevention for malaria in pregnant African women. PQ concentrations of >10.3 ng/ml have been associated with reduced maternal parasitemia, placental malaria, and improved birth outcomes. We characterized the population pharmacokinetics (PK) of PQ in a post hoc analysis of human immunodeficiency virus (HIV)-infected and -uninfected pregnant women receiving DHA-PQ as chemoprevention every 4 or 8 weeks. The effects of covariates such as pregnancy, nutritional status (body mass index [BMI]), and efavirenz (EFV)-based antiretroviral therapy were investigated. PQ concentrations from two chemoprevention trials were pooled to create a population PK database from 274 women and 2,218 PK observations. A three-compartment model with an absorption lag best fit the data. Consistent with our prior intensive PK evaluation, pregnancy and EFV use resulted in a 72% and 61% increased PQ clearance, compared to postpartum and HIV-uninfected pregnant women, respectively. Low BMI at 28 weeks of gestation was associated with increased clearance (2% increase per unit decrease in BMI). Low-BMI women given DHA-PQ every 8 weeks had a higher prevalence of parasitemia, malaria infection, and placental malaria compared to women with higher BMIs. The reduced piperaquine exposure in women with low BMI as well as during EFV coadministration, compared to pregnant women with higher BMIs and not taking EFV, suggests that these populations could benefit from weekly instead of monthly dosing for prevention of malaria parasitemia. Simulations indicated that because of the BMI-clearance relationship, weight-based regimens would not improve protection compared to a 2,880 mg fixed-dose regimen when provided monthly. (The clinical trials described in this paper have been registered at ClinicalTrials.gov under identifiers NCT02163447 and NCT02282293.).
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18
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van Lenthe M, van der Meulen R, Lassovski M, Ouabo A, Bakula E, Badio C, Cibenda D, Okell L, Piriou E, Grignard L, Lanke K, Rao B, Bousema T, Roper C. Markers of sulfadoxine-pyrimethamine resistance in Eastern Democratic Republic of Congo; implications for malaria chemoprevention. Malar J 2019; 18:430. [PMID: 31852480 PMCID: PMC6921399 DOI: 10.1186/s12936-019-3057-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 12/07/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sulfadoxine-pyrimethamine (SP) is a cornerstone of malaria chemoprophylaxis and is considered for programmes in the Democratic Republic of Congo (DRC). However, SP efficacy is threatened by drug resistance, that is conferred by mutations in the dhfr and dhps genes. The World Health Organization has specified that intermittent preventive treatment for infants (IPTi) with SP should be implemented only if the prevalence of the dhps K540E mutation is under 50%. There are limited current data on the prevalence of resistance-conferring mutations available from Eastern DRC. The current study aimed to address this knowledge gap. METHODS Dried blood-spot samples were collected from clinically suspected malaria patients [outpatient department (OPD)] and pregnant women attending antenatal care (ANC) in four sites in North and South Kivu, DRC. Quantitative PCR (qPCR) was performed on samples from individuals with positive and with negative rapid diagnostic test (RDT) results. Dhps K450E and A581G and dhfr I164L were assessed by nested PCR followed by allele-specific primer extension and detection by multiplex bead-based assays. RESULTS Across populations, Plasmodium falciparum parasite prevalence was 47.9% (1160/2421) by RDT and 71.7 (1763/2421) by qPCR. Median parasite density measured by qPCR in RDT-negative qPCR-positive samples was very low with a median of 2.3 parasites/µL (IQR 0.5-25.2). Resistance genotyping was successfully performed in RDT-positive samples and RDT-negative/qPCR-positive samples with success rates of 86.2% (937/1086) and 55.5% (361/651), respectively. The presence of dhps K540E was high across sites (50.3-87.9%), with strong evidence for differences between sites (p < 0.001). Dhps A581G mutants were less prevalent (12.7-47.2%). The dhfr I164L mutation was found in one sample. CONCLUSIONS The prevalence of the SP resistance marker dhps K540E exceeds 50% in all four study sites in North and South Kivu, DRC. K540E mutations regularly co-occurred with mutations in dhps A581G but not with the dhfr I164L mutation. The current results do not support implementation of IPTi with SP in the study area.
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Affiliation(s)
| | - Renske van der Meulen
- Médecins Sans Frontières (MSF), Amsterdam, The Netherlands.,Radboud University Medical Centre, Nijmegen, The Netherlands
| | | | | | | | | | - Deogratias Cibenda
- Programme National de Lutte contre le Paludisme (PNLP) South Kivu, Bukavu, Democratic Republic of Congo
| | | | - Erwan Piriou
- Médecins Sans Frontières (MSF), Amsterdam, The Netherlands
| | - Lynn Grignard
- London School of Hygiene and Tropical Medicine, London, UK
| | - Kjerstin Lanke
- Radboud University Medical Centre, Nijmegen, The Netherlands
| | | | - Teun Bousema
- Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Cally Roper
- London School of Hygiene and Tropical Medicine, London, UK
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Kakuru A, Staedke SG, Dorsey G, Rogerson S, Chandramohan D. Impact of Plasmodium falciparum malaria and intermittent preventive treatment of malaria in pregnancy on the risk of malaria in infants: a systematic review. Malar J 2019; 18:304. [PMID: 31481075 PMCID: PMC6724246 DOI: 10.1186/s12936-019-2943-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/28/2019] [Indexed: 09/16/2023] Open
Abstract
Background Studies of the association between malaria in pregnancy (MiP) and malaria during infancy have provided mixed results. A systematic review was conducted to evaluate available evidence on the impact of Plasmodium falciparum malaria infection during pregnancy, and intermittent preventive treatment of malaria during pregnancy (IPTp), on the risk of clinical malaria or parasitaemia during infancy. Methods MEDLINE, EMBASE, Global Health, and Malaria in Pregnancy Library databases were searched from inception to 22 May 2018 for articles published in English that reported on associations between MiP and malaria risk in infancy. Search terms included malaria, Plasmodium falciparum, pregnancy, placenta, maternal, prenatal, foetal, newborn, infant, child or offspring or preschool. Randomized controlled trials and prospective cohort studies, which followed infants for at least 6 months, were included if any of the following outcomes were reported: incidence of clinical malaria, prevalence of parasitaemia, and time to first episode of parasitaemia or clinical malaria. Substantial heterogeneity between studies precluded meta-analysis. Thus, a narrative synthesis of included studies was conducted. Results The search yielded 14 published studies, 10 prospective cohort studies and four randomized trials; all were conducted in sub-Saharan Africa. Infants born to mothers with parasitaemia during pregnancy were at higher risk of malaria in three of four studies that assessed this association. Placental malaria detected by microscopy or histology was associated with a higher risk of malaria during infancy in nine of 12 studies, but only one study adjusted for malaria transmission intensity. No statistically significant associations between the use of IPTp or different IPTp regimens and the risk of malaria during infancy were identified. Conclusion Evidence of an association between MiP and IPTp and risk of malaria in infancy is limited and of variable quality. Most studies did not adequately adjust for malaria transmission intensity shared by mothers and their infants. Further research is needed to confirm or exclude an association between MiP and malaria in infancy. Randomized trials evaluating highly effective interventions aimed at preventing MiP, such as IPTp with dihydroartemisinin–piperaquine, may help to establish a causal association between MiP and malaria in infancy.
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Affiliation(s)
- Abel Kakuru
- Infectious Diseases Research Collaboration, P.O Box 7475, Kampala, Uganda. .,London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Sarah G Staedke
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Grant Dorsey
- University of California San Francisco, San Francisco, CA, USA
| | - Stephen Rogerson
- Department of Medicine at the Doherty Institute, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, 3000, Australia
| | - Daniel Chandramohan
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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20
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Ngatu NR, Kanbara S, Renzaho A, Wumba R, Mbelambela EP, Muchanga SMJ, Muzembo BA, Leon-Kabamba N, Nattadech C, Suzuki T, Oscar-Luboya N, Wada K, Ikeda M, Nojima S, Sugishita T, Ikeda S. Environmental and sociodemographic factors associated with household malaria burden in the Congo. Malar J 2019; 18:53. [PMID: 30808360 PMCID: PMC6390528 DOI: 10.1186/s12936-019-2679-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 02/14/2019] [Indexed: 11/10/2022] Open
Abstract
Background Malaria is one of the most severe public health issues that result in massive morbidity and mortality in most countries of the sub-Saharan Africa (SSA). This study aimed to determine the scope of household, accessibility to malaria care and factors associated with household malaria in the Democratic Republic of Congo (DRC). Methods This was a community-based cross-sectional study conducted in an urban and a rural sites in which 152 households participated, including 82 urban and 70 rural households (1029 members in total). The ‘malaria indicator questionnaire’ (MIQ) was anonymously answered by household heads (respondents), reporting on malaria status of household members in the last 12 months. Results There were 67.8% of households using insecticide-treated bed nets (ITN) only, 14.0% used indoor residual spraying (IRS) only, 7.3% used ordinary bed nets (without insecticide treatment), 1.4% used mosquito repelling cream, 2.2% combined ITN and IRS, whereas 7.3% of households did not employ any preventive measure; p < 0.01). In addition, 96.7% of households were affected by malaria (at least one malaria case), and malaria frequency per household was relatively high (mean: 4.5 ± 3.1 cases reported) in the last 12 months. The mean individual malaria care expenditure was relatively high (101.6 ± 10.6 USD) in the previous 12 months; however, the majority of households (74.5%) earned less than 50 USD monthly. In addition, of the responders who suffered from malaria, 24.1% did not have access to malaria care at a health setting. Furthermore, a multivariate analysis with adjustment for age, education level and occupation showed that household size (OR = 1.43 ± 0.13; 95% CI 1.18–1.73; p < 0.001), inappropriate water source (OR = 2.41 ± 0.18; 95% CI 1.17–2.96; p < 0.05) absence of periodic water, sanitation and hygiene (WASH) intervention in residential area (OR = 1.63 ± 1.15; 95% CI 1.10–2.54; p < 0.05), and rural residence (OR = 4.52 ± 2.47; 95% CI 1.54–13.21; p < 0.01) were associated with household malaria. Conclusion This study showed that household size, income, WASH status and rural site were malaria-associated factors. Scaling up malaria prevention through improving WASH status in the residential environment may contribute to reducing the disease burden.
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Affiliation(s)
- Nlandu Roger Ngatu
- School of Medicine and Graduate School of Public Health, International University of Health and Welfare, Narita, Japan.
| | - Sakiko Kanbara
- Graduate School of Nursing, University of Kochi, Kochi, Japan
| | | | - Roger Wumba
- Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Etongola P Mbelambela
- Department of Environmental Medicine, Kochi University Medical School, Nankoku, Japan
| | | | - Basilua Andre Muzembo
- School of Medicine and Graduate School of Public Health, International University of Health and Welfare, Narita, Japan
| | - Ngombe Leon-Kabamba
- Department of Public Health, University of Kamina, Kamina, Democratic Republic of the Congo
| | - Choomplang Nattadech
- School of Medicine and Graduate School of Public Health, International University of Health and Welfare, Narita, Japan
| | - Tomoko Suzuki
- School of Medicine and Graduate School of Public Health, International University of Health and Welfare, Narita, Japan
| | - Numbi Oscar-Luboya
- School of Public Health, University of Lubumbashi, Lubumbashi, Democratic Republic of the Congo
| | - Koji Wada
- School of Medicine and Graduate School of Public Health, International University of Health and Welfare, Narita, Japan
| | - Mitsunori Ikeda
- Graduate School of Nursing, University of Kochi, Kochi, Japan
| | - Sayumi Nojima
- Graduate School of Nursing, University of Kochi, Kochi, Japan
| | | | - Shunya Ikeda
- School of Medicine and Graduate School of Public Health, International University of Health and Welfare, Narita, Japan
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21
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Amimo F, Moon TD, Magit A, Sacarlal J, Lambert B, Nomura S. Trends in comparative efficacy and safety of malaria control interventions for maternal and child health outcomes in Africa: a study protocol for a Bayesian network meta-regression exploring the effect of HIV and malaria endemicity spectrum. BMJ Open 2019; 9:e024313. [PMID: 30798310 PMCID: PMC6398739 DOI: 10.1136/bmjopen-2018-024313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 11/05/2018] [Accepted: 12/18/2018] [Indexed: 01/25/2023] Open
Abstract
INTRODUCTION Unprecedented global efforts to prevent malaria morbidity and mortality in sub-Saharan Africa have saved hundreds of thousands of lives across the continent in the last two decades. This study aims to determine how the comparative efficacy and safety of available malaria control interventions intended to improve maternal and child health outcomes have changed over time considering the varied epidemiological contexts on the continent. METHODS We will review all randomised controlled trials that investigated malaria control interventions in pregnant women in sub-Saharan Africa and were published between January 1980 and December 2018. We will subsequently use network meta-regression to estimate temporal trends in the relative and absolute efficacy and safety of Intermittent Preventive Treatments, Intermittent Screening and Treatments, Insecticide-treated bed nets, and their combinations, and predict their ranking according to their relative and absolute efficacy and safety over time. Our outcomes will include 12 maternal and 7 child mortality and morbidity outcomes, known to be associated with either malaria infection or control. We will use intention-to-treat analysis to derive our estimates and meta-regression to estimate temporal trends and the effect modification by HIV infection, malaria endemicity and Plasmodium falciparum resistance to sulfadoxine-pyrimethamine, while adjusting for multiple potential confounders via propensity score calibration. PROSPERO REGISTRATION NUMBER CRD42018095138.
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Affiliation(s)
- Floriano Amimo
- Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Troy D Moon
- Division of Infectious Diseases, Vanderbilt Institute for Global Health, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Anthony Magit
- Human Research Protection Program, University of California San Diego School of Medicine, San Diego, California, USA
| | - Jahit Sacarlal
- Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Ben Lambert
- MRC Centre for Outbreak Analysis and Modelling, Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Shuhei Nomura
- Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Marealle AI, Mbwambo DP, Mikomangwa WP, Kilonzi M, Mlyuka HJ, Mutagonda RF. A decade since sulfonamide-based anti-malarial medicines were limited for intermittent preventive treatment of malaria among pregnant women in Tanzania. Malar J 2018; 17:409. [PMID: 30400908 PMCID: PMC6219183 DOI: 10.1186/s12936-018-2565-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/01/2018] [Indexed: 11/10/2022] Open
Abstract
Background Despite the development of resistance to Plasmodium falciparum malaria, sulfadoxine–pyrimethamine is still effective for intermittent preventive treatment of malaria in pregnancy (IPTp). In Tanzania, more than 10 years have passed since sulfadoxine–pyrimethamine and sulfamethopyrazine–pyrimethamine (SPs) were reserved for IPTp only. However, the retail pharmaceutical outlet dispensers’ knowledge and their compliance with the policies have not been recently explored. Therefore, this study was designed to investigate dispensers’ knowledge about these medications together with their actual dispensing practices, a decade since they were limited for IPTp use only. Methods This descriptive cross-sectional study was conducted between February and July 2017 in all municipalities of Dar-es-Salaam city. Data were collected by direct interviews using a structured questionnaire to assess knowledge and a simulated client approach was used to assess the actual practice of medicine dispensers. Data analysis was done by using SPSS version 20 and Chi square test was used to test significant differences in proportions between different categorical variables. A p-value of less than 0.05 was considered to be statistically significant. Results A random sample of 422 medicine dispensers participated in this study whereby 185 (43.8%) were from community pharmacies and 237 (56.2%) from accredited drug dispensing outlets. The study revealed that SPs were available in 76% of the community pharmaceutical outlets in Dar es Salaam. In general majority of the dispensers (64%) had moderate to high knowledge about SPs and their indication. About 80% of the dispensers were aware that SP is reserved for IPTp. However, irrespective of the level of knowledge, almost all dispensers (92%) were willing to dispense the medicines for the purpose of treating malaria, contrary to the current Tanzania malaria treatment guideline. Conclusion Majority of the medicine dispensers in the community pharmaceutical outlets were knowledgeable about SPs and their indications. Disappointingly, almost all dispensers irrespective of their levels of knowledge were willing to dispense SPs for treatment of malaria contrary to the available treatment guidelines.
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Affiliation(s)
- Alphonce I Marealle
- Department of Clinical Pharmacy & Pharmacology, School of Pharmacy, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania.
| | - Dennis P Mbwambo
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Wigilya P Mikomangwa
- Department of Clinical Pharmacy & Pharmacology, School of Pharmacy, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania
| | - Manase Kilonzi
- Department of Clinical Pharmacy & Pharmacology, School of Pharmacy, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania
| | - Hamu J Mlyuka
- Department of Clinical Pharmacy & Pharmacology, School of Pharmacy, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania
| | - Ritah F Mutagonda
- Department of Clinical Pharmacy & Pharmacology, School of Pharmacy, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania
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Druetz T, Corneau-Tremblay N, Millogo T, Kouanda S, Ly A, Bicaba A, Haddad S. Impact Evaluation of Seasonal Malaria Chemoprevention under Routine Program Implementation: A Quasi-Experimental Study in Burkina Faso. Am J Trop Med Hyg 2017; 98:524-533. [PMID: 29260654 PMCID: PMC5929206 DOI: 10.4269/ajtmh.17-0599] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Seasonal malaria chemoprevention (SMC) for children < 5 is a strategy that is gaining popularity in West African countries. Although its efficacy to reduce malaria incidence has been demonstrated in trials, the effects of SMC implemented in routine program conditions, outside of experimental contexts, are unknown. In 2014 and 2015, a survey was conducted in 1,311 households located in Kaya District (Burkina Faso) where SMC had been recently introduced. All children < 72 months were tested for malaria and anemia. A pre–post study with control group was designed to measure SMC impact during high transmission season. A difference-in-differences approach was coupled in the analysis with propensity score weighting to control for observable and time-invariant nonobservable confounding factors. SMC reduced the parasitemia point and period prevalence by 3.3 and 24% points, respectively; this translated into protective effects of 51% and 62%. SMC also reduced the likelihood of having moderate to severe anemia by 32%, and history of recent fever by 46%. Self-reported coverage for children at the first cycle was 83%. The SMC program was successfully added to a package of interventions already in place. To our knowledge, with prevalence < 10% during the peak of the transmission season, this is the first time that malaria can be reported as hypo-endemic in a sub-Sahelian setting in Burkina Faso. SMC has great potential, and along with other interventions, it could contribute to approaching the threshold where elimination strategies will be envisioned in Burkina Faso.
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Affiliation(s)
- Thomas Druetz
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
| | | | - Tieba Millogo
- Institut de Recherche en Sciences de la Santé, Ouagadougou, Burkina Faso
| | - Seni Kouanda
- Institut de Recherche en Sciences de la Santé, Ouagadougou, Burkina Faso
| | - Antarou Ly
- Department of Preventive and Social Medicine, Faculty of Medicine, Laval University, Quebec City, Canada
| | - Abel Bicaba
- Société d'Études et de Recherches en Santé Publique, Ouagadougou, Burkina Faso
| | - Slim Haddad
- Department of Preventive and Social Medicine, Faculty of Medicine, Laval University, Quebec City, Canada
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Conrad MD, Mota D, Foster M, Tukwasibwe S, Legac J, Tumwebaze P, Whalen M, Kakuru A, Nayebare P, Wallender E, Havlir DV, Jagannathan P, Huang L, Aweeka F, Kamya MR, Dorsey G, Rosenthal PJ. Impact of Intermittent Preventive Treatment During Pregnancy on Plasmodium falciparum Drug Resistance-Mediating Polymorphisms in Uganda. J Infect Dis 2017; 216:1008-1017. [PMID: 28968782 PMCID: PMC5853776 DOI: 10.1093/infdis/jix421] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 08/17/2017] [Indexed: 11/13/2022] Open
Abstract
Background In a recent trial of intermittent preventive treatment in pregnancy (IPTp) in Uganda, dihydroartemisinin-piperaquine (DP) was superior to sulfadoxine-pyrimethamine (SP) in preventing maternal and placental malaria. Methods We compared genotypes using sequencing, fluorescent microsphere, and quantitative polymerase chain reaction assays at loci associated with drug resistance in Plasmodium falciparum isolated from subjects receiving DP or SP. Results Considering aminoquinoline resistance, DP was associated with increased prevalences of mutations at pfmdr1 N86Y, pfmdr1 Y184F, and pfcrt K76T compared to SP (64.6% vs 27.4%, P < .001; 93.9% vs 59.2%, P < .001; and 87.7% vs 75.4%, P = .03, respectively). Increasing plasma piperaquine concentration at the time of parasitemia was associated with increasing pfmdr1 86Y prevalence; no infections with the N86 genotype occurred with piperaquine >2.75 ng/mL. pfkelch13 propeller domain polymorphisms previously associated with artemisinin resistance were not identified. Recently identified markers of piperaquine resistance were uncommon and not associated with DP. Considering antifolate resistance, SP was associated with increased prevalence of a 5-mutation haplotype (pfdhfr 51I, 59R, and 108N; pfdhps 437G and 581G) compared to DP (90.8% vs 60.0%, P = .001). Conclusions IPTp selected for genotypes associated with decreased sensitivity to treatment regimens, but genotypes associated with clinically relevant DP resistance in Asia have not emerged in Uganda.
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Affiliation(s)
| | | | | | | | | | | | | | - Abel Kakuru
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | | | - Prasanna Jagannathan
- University of California, San Francisco,Stanford University, Palo Alto, California
| | | | | | - Moses R Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda,Makerere University College of Health Sciences, Kampala, Uganda
| | | | - Philip J Rosenthal
- University of California, San Francisco,Correspondence: P. J. Rosenthal, University of California, San Francisco, Box 0811, San Francisco, CA 94143 ()
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25
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Natureeba P, Kakuru A, Muhindo M, Ochieng T, Ategeka J, Koss CA, Plenty A, Charlebois ED, Clark TD, Nzarubara B, Nakalembe M, Cohan D, Rizzuto G, Muehlenbachs A, Ruel T, Jagannathan P, Havlir DV, Kamya MR, Dorsey G. Intermittent Preventive Treatment With Dihydroartemisinin-Piperaquine for the Prevention of Malaria Among HIV-Infected Pregnant Women. J Infect Dis 2017; 216:29-35. [PMID: 28329368 DOI: 10.1093/infdis/jix110] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Accepted: 02/21/2017] [Indexed: 11/13/2022] Open
Abstract
Background Daily trimethoprim-sulfamethoxazole (TMP-SMX) and insecticide-treated nets remain the main interventions for prevention of malaria in human immunodeficiency virus (HIV)-infected pregnant women in Africa. However, antifolate and pyrethroid resistance threaten the effectiveness of these interventions, and new ones are needed. Methods We conducted a double-blinded, randomized, placebo-controlled trial comparing daily TMP-SMX plus monthly dihydroartemisinin-piperaquine (DP) to daily TMP-SMX alone in HIV-infected pregnant women in an area of Uganda where indoor residual spraying of insecticide had recently been implemented. Participants were enrolled between gestation weeks 12 and 28 and given an insecticide-treated net. The primary outcome was detection of active or past placental malarial infection by histopathologic analysis. Secondary outcomes included incidence of malaria, parasite prevalence, and adverse birth outcomes. Result All 200 women enrolled were followed through delivery, and the primary outcome was assessed in 194. There was no statistically significant difference in the risk of histopathologically detected placental malarial infection between the daily TMP-SMX plus DP arm and the daily TMP-SMX alone arm (6.1% vs. 3.1%; relative risk, 1.96; 95% confidence interval, .50-7.61; P = .50). Similarly, there were no differences in secondary outcomes. Conclusions Among HIV-infected pregnant women in the setting of indoor residual spraying of insecticide, adding monthly DP to daily TMP-SMX did not reduce the risk of placental or maternal malaria or improve birth outcomes. Clinical Trials Registration NCT02282293.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Atis Muehlenbachs
- Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | | | | | - Moses R Kamya
- School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
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26
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Kajubi R, Huang L, Jagannathan P, Chamankhah N, Were M, Ruel T, Koss CA, Kakuru A, Mwebaza N, Kamya M, Havlir D, Dorsey G, Rosenthal PJ, Aweeka FT. Antiretroviral Therapy With Efavirenz Accentuates Pregnancy-Associated Reduction of Dihydroartemisinin-Piperaquine Exposure During Malaria Chemoprevention. Clin Pharmacol Ther 2017; 102:520-528. [PMID: 28187497 PMCID: PMC5546920 DOI: 10.1002/cpt.664] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 02/02/2017] [Accepted: 02/03/2017] [Indexed: 11/08/2022]
Abstract
Dihydroartemisinin (DHA)-piperaquine is promising for malaria chemoprevention in pregnancy. We assessed the impacts of pregnancy and efavirenz-based antiretroviral therapy on exposure to DHA and piperaquine in pregnant Ugandan women. Intensive sampling was performed at 28 weeks gestation in 31 HIV-uninfected pregnant women, in 27 HIV-infected pregnant women receiving efavirenz, and in 30 HIV-uninfected nonpregnant women. DHA peak concentration and area under the concentration time curve (AUC0-8hr ) were 50% and 47% lower, respectively, and piperaquine AUC0-21d was 40% lower in pregnant women compared to nonpregnant women. DHA AUC0-8hr and piperaquine AUC0-21d were 27% and 38% lower, respectively, in pregnant women receiving efavirenz compared to HIV-uninfected pregnant women. Exposure to DHA and piperaquine were lower among pregnant women and particularly in women on efavirenz, suggesting a need for dose modifications. The study of modified dosing strategies for these populations is urgently needed.
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Affiliation(s)
- Richard Kajubi
- Infectious Disease Research Collaboration, Makerere University
College of Health Sciences- all in Kampala, Uganda
- Department of Pharmacology and Therapeutics, Makerere University
College of Health Sciences- all in Kampala, Uganda
| | - Liusheng Huang
- Department of Clinical Pharmacy, University of California, San
Francisco, San Francisco General Hospital, San Francisco, CA, USA
| | - Prasanna Jagannathan
- Department of Medicine, University of California, San Francisco, San
Francisco General Hospital, San Francisco, CA, USA
| | - Nona Chamankhah
- Department of Clinical Pharmacy, University of California, San
Francisco, San Francisco General Hospital, San Francisco, CA, USA
| | - Moses Were
- Infectious Disease Research Collaboration, Makerere University
College of Health Sciences- all in Kampala, Uganda
| | - Theodore. Ruel
- Department of Pediatrics, University of California, San Francisco,
San Francisco General Hospital, San Francisco, CA, USA
| | - Catherine A. Koss
- Department of Medicine, University of California, San Francisco, San
Francisco General Hospital, San Francisco, CA, USA
| | - Abel Kakuru
- Infectious Disease Research Collaboration, Makerere University
College of Health Sciences- all in Kampala, Uganda
| | - Norah Mwebaza
- Infectious Disease Research Collaboration, Makerere University
College of Health Sciences- all in Kampala, Uganda
- Department of Pharmacology and Therapeutics, Makerere University
College of Health Sciences- all in Kampala, Uganda
| | - Moses Kamya
- Infectious Disease Research Collaboration, Makerere University
College of Health Sciences- all in Kampala, Uganda
| | - Diane Havlir
- Department of Medicine, University of California, San Francisco, San
Francisco General Hospital, San Francisco, CA, USA
| | - Grant Dorsey
- Department of Medicine, University of California, San Francisco, San
Francisco General Hospital, San Francisco, CA, USA
| | - Philip J. Rosenthal
- Department of Medicine, University of California, San Francisco, San
Francisco General Hospital, San Francisco, CA, USA
| | - Francesca T. Aweeka
- Department of Clinical Pharmacy, University of California, San
Francisco, San Francisco General Hospital, San Francisco, CA, USA
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27
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Presence of quintuple dhfr N51, C59, S108 - dhps A437, K540 mutations in Plasmodium falciparum isolates from pregnant women and the general population in Nanoro, Burkina Faso. Mol Biochem Parasitol 2017; 217:13-15. [PMID: 28818675 DOI: 10.1016/j.molbiopara.2017.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/21/2017] [Accepted: 08/06/2017] [Indexed: 11/21/2022]
Abstract
Sulphadoxine-pyrimethamine (SP) is only used for intermittent preventive treatment during pregnancy (IPTp) in most Sub-Saharan African countries. However, there are concerns about the efficacy of IPTp-SP because of increasing resistance. Combinations of point mutations in the dhps and dhfr genes of Plasmodium falciparum are associated with SP resistance, in particular the quintuple dhfr (N51, C59, S108) - dhps (codons A437, K540) mutant. In Nanoro, Burkina Faso, filter paper samples from pregnant women at first antenatal care visit and at delivery plus samples from the general population (GP) were studied for dhfr and dhps mutations by sequencing. Quintuple mutants were present in 2 delivery and 4 GP samples. This is the first time the quintuple mutation is found in Burkina Faso and although the prevalence is still very low, emergence of the quintuple mutation could highly diminish the efficacy of IPTp-SP. Close surveillance of SP resistance mutations is therefore warranted.
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28
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Ruizendaal E, Schallig HDFH, Scott S, Traore-Coulibaly M, Bradley J, Lompo P, Natama HM, Traore O, Valea I, Dierickx S, Drabo KM, Pagnoni F, Alessandro UD, Tinto H, Mens PF. Evaluation of Malaria Screening during Pregnancy with Rapid Diagnostic Tests Performed by Community Health Workers in Burkina Faso. Am J Trop Med Hyg 2017; 97:1190-1197. [PMID: 28722627 DOI: 10.4269/ajtmh.17-0138] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
One of the current strategies to prevent malaria in pregnancy is intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP). However, in order for pregnant women to receive an adequate number of SP doses, they should attend a health facility on a regular basis. In addition, SP resistance may decrease IPTp-SP efficacy. New or additional interventions for preventing malaria during pregnancy are therefore warranted. Because it is known that community health workers (CHWs) can diagnose and treat malaria in children, in this study screening and treatment of malaria in pregnancy by CHWs was evaluated as an addition to the regular IPTp-SP program. CHWs used rapid diagnostic tests (RDTs) for screening and artemether-lumefantrine was given in case of a positive RDT. Overall, CHWs were able to conduct RDTs with a sensitivity of 81.5% (95% confidence interval [CI] 67.9-90.2) and high specificity of 92.1% (95% CI 89.9-93.9) compared with microscopy. After a positive RDT, 79.1% of women received artemether-lumefantrine. When treatment was not given, this was largely due to the woman being already under treatment. Almost all treated women finished the full course of artemether-lumefantrine (96.4%). In conclusion, CHWs are capable of performing RDTs with high specificity and acceptable sensitivity, the latter being dependent on the limit of detection of RDTs. Furthermore, CHWs showed excellent adherence to test results and treatment guidelines, suggesting they can be deployed for screen and treat approaches of malaria in pregnancy.
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Affiliation(s)
- Esmée Ruizendaal
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Henk D F H Schallig
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Susana Scott
- Disease Control and Elimination, Medical Research Council Unit, Fajara, The Gambia.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Maminata Traore-Coulibaly
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - John Bradley
- Medical Research Council (MRC) Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Palpouguini Lompo
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Hamtandi M Natama
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Ousmane Traore
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Innocent Valea
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Susan Dierickx
- Amsterdam Institute of Social Science Research, Amsterdam, The Netherlands.,Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Koiné M Drabo
- Institut de Recherche en Sciences de la Santé (IRSS), Ouagadougou, Burkina Faso
| | | | - Umberto d' Alessandro
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Disease Control and Elimination, Medical Research Council Unit, Fajara, The Gambia
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Petra F Mens
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
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29
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Ndam NT, Mbuba E, González R, Cisteró P, Kariuki S, Sevene E, Rupérez M, Fonseca AM, Vala A, Maculuve S, Jiménez A, Quintó L, Ouma P, Ramharter M, Aponte JJ, Nhacolo A, Massougbodji A, Briand V, Kremsner PG, Mombo-Ngoma G, Desai M, Macete E, Cot M, Menéndez C, Mayor A. Resisting and tolerating P. falciparum in pregnancy under different malaria transmission intensities. BMC Med 2017; 15:130. [PMID: 28712360 PMCID: PMC5513247 DOI: 10.1186/s12916-017-0893-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 06/15/2017] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Resistance and tolerance to Plasmodium falciparum can determine the progression of malaria disease. However, quantitative evidence of tolerance is still limited. We investigated variations in the adverse impact of P. falciparum infections among African pregnant women under different intensities of malaria transmission. METHODS P. falciparum at delivery was assessed by microscopy, quantitative PCR (qPCR) and placental histology in 946 HIV-uninfected and 768 HIV-infected pregnant women from Benin, Gabon, Kenya and Mozambique. Resistance was defined by the proportion of submicroscopic infections and the levels of anti-parasite antibodies quantified by Luminex, and tolerance by the relationship of pregnancy outcomes with parasite densities at delivery. RESULTS P. falciparum prevalence by qPCR in peripheral and/or placental blood of HIV-uninfected Mozambican, Gabonese and Beninese women at delivery was 6% (21/340), 11% (28/257) and 41% (143/349), respectively. The proportion of peripheral submicroscopic infections was higher in Benin (83%) than in Mozambique (60%) and Gabon (55%; P = 0.033). Past or chronic placental P. falciparum infection was associated with an increased risk of preterm birth in Mozambican newborns (OR = 7.05, 95% CI 1.79 to 27.82). Microscopic infections were associated with reductions in haemoglobin levels at delivery among Mozambican women (-1.17 g/dL, 95% CI -2.09 to -0.24) as well as with larger drops in haemoglobin levels from recruitment to delivery in Mozambican (-1.66 g/dL, 95% CI -2.68 to -0.64) and Gabonese (-0.91 g/dL, 95% CI -1.79 to -0.02) women. Doubling qPCR-peripheral parasite densities in Mozambican women were associated with decreases in haemoglobin levels at delivery (-0.16 g/dL, 95% CI -0.29 to -0.02) and increases in the drop of haemoglobin levels (-0.29 g/dL, 95% CI -0.44 to -0.14). Beninese women had higher anti-parasite IgGs than Mozambican women (P < 0.001). No difference was found in the proportion of submicroscopic infections nor in the adverse impact of P. falciparum infections in HIV-infected women from Kenya (P. falciparum prevalence by qPCR: 9%, 32/351) and Mozambique (4%, 15/417). CONCLUSIONS The lowest levels of resistance and tolerance in pregnant women from areas of low malaria transmission were accompanied by the largest adverse impact of P. falciparum infections. Exposure-dependent mechanisms developed by pregnant women to resist the infection and minimise pathology can reduce malaria-related adverse outcomes. Distinguishing both types of defences is important to understand how reductions in transmission can affect malaria disease. TRIAL REGISTRATION ClinicalTrials.gov NCT00811421 . Registered 18 December 2008.
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Affiliation(s)
- Nicaise Tuikue Ndam
- Institut de Recherche pour le Développement (IRD), Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie, Paris, France.,Faculté des Sciences de la Santé (FSS), Université d'Aboméy Calavi, Cotonou, Benin
| | - Emmanuel Mbuba
- Ifakara Health Institute (IHI), Bagamoyo Research and Training Centre (BRTC), Bagamoyo, Tanzania
| | - Raquel González
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Pau Cisteró
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Simon Kariuki
- Kenya Medical Research Institute (KEMRI)/Centre for Global Health Research, Kisumu, Kenya
| | - Esperança Sevene
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique.,Universidade Eduardo Mondlane, Maputo, Mozambique
| | - María Rupérez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Ana Maria Fonseca
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Graduate Program in Areas of Basic and Applied Biology, Universidade do Porto, Porto, Portugal
| | - Anifa Vala
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Sonia Maculuve
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Alfons Jiménez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Llorenç Quintó
- Faculté des Sciences de la Santé (FSS), Université d'Aboméy Calavi, Cotonou, Benin
| | - Peter Ouma
- Kenya Medical Research Institute (KEMRI)/Centre for Global Health Research, Kisumu, Kenya
| | - Michael Ramharter
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - John J Aponte
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Arsenio Nhacolo
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Achille Massougbodji
- Faculté des Sciences de la Santé (FSS), Université d'Aboméy Calavi, Cotonou, Benin
| | - Valerie Briand
- Institut de Recherche pour le Développement (IRD), Paris, France
| | - Peter G Kremsner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Ghyslain Mombo-Ngoma
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Meghna Desai
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Eusebio Macete
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Michel Cot
- Institut de Recherche pour le Développement (IRD), Paris, France
| | - Clara Menéndez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Alfredo Mayor
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain. .,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique.
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30
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Ruizendaal E, Tahita MC, Geskus RB, Versteeg I, Scott S, d'Alessandro U, Lompo P, Derra K, Traore-Coulibaly M, de Jong MD, Schallig HDFH, Tinto H, Mens PF. Increase in the prevalence of mutations associated with sulfadoxine-pyrimethamine resistance in Plasmodium falciparum isolates collected from early to late pregnancy in Nanoro, Burkina Faso. Malar J 2017; 16:179. [PMID: 28454537 PMCID: PMC5410088 DOI: 10.1186/s12936-017-1831-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/23/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pregnant women are a high-risk group for Plasmodium falciparum infections, which may result in maternal anaemia and low birth weight newborns, among other adverse birth outcomes. Intermittent preventive treatment with sulfadoxine-pyrimethamine during pregnancy (IPTp-SP) is widely implemented to prevent these negative effects of malaria. However, resistance against SP by P. falciparum may decrease efficacy of IPTp-SP. Combinations of point mutations in the dhps (codons A437, K540) and dhfr genes (codons N51, C59, S108) of P. falciparum are associated with SP resistance. In this study the prevalence of SP resistance mutations was determined among P. falciparum found in pregnant women and the general population (GP) from Nanoro, Burkina Faso and the association of IPTp-SP dosing and other variables with mutations was studied. METHODS Blood spots on filter papers were collected from pregnant women at their first antenatal care visit (ANC booking) and at delivery, from an ongoing trial and from the GP in a cross-sectional survey. The dhps and dhfr genes were amplified by nested PCR and products were sequenced to identify mutations conferring resistance (ANC booking, n = 400; delivery, n = 223; GP, n = 400). Prevalence was estimated with generalized estimating equations and for multivariate analyses mixed effects logistic regression was used. RESULTS The prevalence of the triple dhfr mutation was high, and significantly higher in the GP and at delivery than at ANC booking, but it did not affect birth weight. Furthermore, quintuple mutations (triple dhfr and double dhps mutations) were found for the first time in Burkina Faso. IPTp-SP did not significantly affect the occurrence of any of the mutations, but high transmission season was associated with increased mutation prevalence in delivery samples. It is unclear why the prevalence of mutations was higher in the GP than in pregnant women at ANC booking. CONCLUSION The high number of mutants and the presence of quintuple mutants in Burkina Faso confirm concerns about the efficacy of IPTp-SP in the near future. Other drug combinations to tackle malaria in pregnancy should, therefore, be explored. An increase in mutation prevalence due to IPTp-SP dosing could not be confirmed.
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Affiliation(s)
- Esmée Ruizendaal
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands.
| | - Marc C Tahita
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Ronald B Geskus
- Department of Clinical Epidemiology, Biostatistic and Bioinformatics, Academic Medical Centre, Amsterdam, The Netherlands.,Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Viet Nam
| | - Inge Versteeg
- Koninklijk Instituut voor de Tropen, Amsterdam, The Netherlands
| | - Susana Scott
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.,Disease Control and Elimination, Medical Research Council Unit, Fajara, Gambia
| | - Umberto d'Alessandro
- Disease Control and Elimination, Medical Research Council Unit, Fajara, Gambia.,Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Palpouguini Lompo
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Karim Derra
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Maminata Traore-Coulibaly
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Menno D de Jong
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Henk D F H Schallig
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé-Unité de Recherche Clinique de Nanoro, (IRSS-URCN), Nanoro, Burkina Faso
| | - Petra F Mens
- Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
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31
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Lynch CA, Pearce R, Pota H, Egwang C, Egwang T, Bhasin A, Cox J, Abeku TA, Roper C. Travel and the emergence of high-level drug resistance in Plasmodium falciparum in southwest Uganda: results from a population-based study. Malar J 2017; 16:150. [PMID: 28415996 PMCID: PMC5392983 DOI: 10.1186/s12936-017-1812-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 04/08/2017] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND The I164L mutation on the dhfr gene confers high level resistance to sulfadoxine-pyrimethamine (SP) but it is rare in Africa except in a cluster of reports where prevalence >10% in highland areas of southwest Uganda and eastern Rwanda. The occurrence of the dhfr I164L mutation was investigated in community surveys in this area and examined the relationship to migration. METHODS A cross-sectional prevalence survey was undertaken in among villages within the catchment areas of two health facilities in a highland site (Kabale) and a highland fringe site (Rukungiri) in 2007. Sociodemographic details, including recent migration, were collected for each person included in the study. A total of 206 Plasmodium falciparum positive subjects were detected by rapid diagnostic test; 203 in Rukungiri and 3 in Kabale. Bloodspot samples were taken and were screened for dhfr I164L. RESULTS Sequence analysis confirmed the presence of the I164L mutations in twelve P. falciparum positive samples giving an estimated prevalence of 8.6% in Rukungiri. Of the three parasite positive samples in Kabale, none had I164L mutations. Among the twelve I164L positives three were male, ages ranged from 5 to 90 years of age. None of those with the I164L mutation had travelled in the 8 weeks prior to the survey, although three were from households from which at least one household member had travelled during that period. Haplotypes were determined in non-mixed infections and showed the dhfr I164L mutation occurs in both as a N51I + S108N + I164L haplotype (n = 2) and N51I + C59R + S108N + I164L haplotype (n = 5). Genotyping of flanking microsatellite markers showed that the I164L occurred independently on the triple mutant (N51I, C59R + S108N) and double mutant (N51I + S108N) background. CONCLUSIONS There is sustained local transmission of parasites with the dhfr I164L mutation in Rukungiri and no evidence to indicate its occurrence is associated with recent travel to highly resistant neighbouring areas. The emergence of a regional cluster of I164L in SW Uganda and Rwanda indicates that transmission of I164L is facilitated by strong drug pressure in low transmission areas potentially catalysed in those areas by travel and the importation of parasites from relatively higher transmission settings.
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Affiliation(s)
- Caroline A Lynch
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
| | - Richard Pearce
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Hirva Pota
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | | | | | - Amit Bhasin
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Jonathan Cox
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | | | - Cally Roper
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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Guerra M, Neres R, Salgueiro P, Mendes C, Ndong-Mabale N, Berzosa P, de Sousa B, Arez AP. Plasmodium falciparum Genetic Diversity in Continental Equatorial Guinea before and after Introduction of Artemisinin-Based Combination Therapy. Antimicrob Agents Chemother 2017; 61:e02556-15. [PMID: 27795385 PMCID: PMC5192141 DOI: 10.1128/aac.02556-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 10/17/2016] [Indexed: 11/20/2022] Open
Abstract
Efforts to control malaria may affect malaria parasite genetic variability and drug resistance, the latter of which is associated with genetic events that promote mechanisms to escape drug action. The worldwide spread of drug resistance has been a major obstacle to controlling Plasmodium falciparum malaria, and thus the study of the origin and spread of associated mutations may provide some insights into the prevention of its emergence. This study reports an analysis of P. falciparum genetic diversity, focusing on antimalarial resistance-associated molecular markers in two socioeconomically different villages in mainland Equatorial Guinea. The present study took place 8 years after a previous one, allowing the analysis of results before and after the introduction of an artemisinin-based combination therapy (ACT), i.e., artesunate plus amodiaquine. Genetic diversity was assessed by analysis of the Pfmsp2 gene and neutral microsatellite loci. Pfdhps and Pfdhfr alleles associated with sulfadoxine-pyrimethamine (SP) resistance and flanking microsatellite loci were investigated, and the prevalences of drug resistance-associated point mutations of the Pfcrt, Pfmdr1, Pfdhfr, and Pfdhps genes were estimated. Further, to monitor the use of ACT, we provide the baseline prevalences of K13 propeller mutations and Pfmdr1 copy numbers. After 8 years, noticeable differences occurred in the distribution of genotypes conferring resistance to chloroquine and SP, and the spread of mutated genotypes differed according to the setting. Regarding artemisinin resistance, although mutations reported as being linked to artemisinin resistance were not present at the time, several single nucleotide polymorphisms (SNPs) were observed in the K13 gene, suggesting that closer monitoring should be maintained to prevent the possible spread of artemisinin resistance in Africa.
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Affiliation(s)
- Mónica Guerra
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisbon, Portugal
| | - Rita Neres
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisbon, Portugal
| | - Patrícia Salgueiro
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisbon, Portugal
| | - Cristina Mendes
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisbon, Portugal
| | - Nicolas Ndong-Mabale
- Centro de Referencia para el Control de Endemias, Instituto de Salud Carlos III, Bata, Equatorial Guinea
| | - Pedro Berzosa
- Centro Nacional de Medicina Tropical, Instituto de Salud Carlos III, Madrid, Spain
| | - Bruno de Sousa
- Faculdade de Psicologia e de Ciências da Educação, Universidade de Coimbra, Coimbra, Portugal
| | - Ana Paula Arez
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Lisbon, Portugal
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Oguike MC, Falade CO, Shu E, Enato IG, Watila I, Baba ES, Bruce J, Webster J, Hamade P, Meek S, Chandramohan D, Sutherland CJ, Warhurst D, Roper C. Molecular determinants of sulfadoxine-pyrimethamine resistance in Plasmodium falciparum in Nigeria and the regional emergence of dhps 431V. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2016; 6:220-229. [PMID: 27821281 PMCID: PMC5094156 DOI: 10.1016/j.ijpddr.2016.08.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 08/12/2016] [Indexed: 11/19/2022]
Abstract
There are few published reports of mutations in dihydropteroate synthetase (dhps) and dihydrofolate reductase (dhfr) genes in P. falciparum populations in Nigeria, but one previous study has recorded a novel dhps mutation at codon 431 among infections imported to the United Kingdom from Nigeria. To assess how widespread this mutation is among parasites in different parts of the country and consequently fill the gap in sulfadoxine-pyrimethamine (SP) resistance data in Nigeria, we retrospectively analysed 1000 filter paper blood spots collected in surveys of pregnant women and children with uncomplicated falciparum malaria between 2003 and 2015 from four sites in the south and north. Genomic DNA was extracted from filter paper blood spots and placental impressions. Point mutations at codons 16, 50, 51, 59, 108, 140 and 164 of the dhfr gene and codons 431, 436, 437, 540, 581 and 613 of the dhps gene were evaluated by nested PCR amplification followed by direct sequencing. The distribution of the dhps-431V mutation was widespread throughout Nigeria with the highest prevalence in Enugu (46%). In Ibadan where we had sequential sampling, its prevalence increased from 0% to 6.5% between 2003 and 2008. Although there were various combinations of dhps mutations with 431V, the combination 431V + 436A + 437G+581G+613S was the most common. All these observations support the view that dhps-431V is on the increase. In addition, P. falciparum DHPS crystal structure modelling shows that the change from Isoleucine to Valine (dhps-431V) could alter the effects of both S436A/F and A437G, which closely follow the 2nd β-strand. Consequently, it is now a research priority to assess the implications of dhps-VAGKGS mutant haplotype on continuing use of SP in seasonal malaria chemoprevention (SMC) and intermittent preventive treatment in pregnancy (IPTp). Our data also provides surveillance data for SP resistance markers in Nigeria between 2003 and 2015. We present data on dhps and dhfr mutations in P. falciparum populations in Nigeria. Increased prevalence of I431V mutation was seen between 2003 and 2015 from 0 to 36%. The 431V + 436A + 437G + 581G + 613S was the most common with dhps-431V mutation. Crystal structure modelling of Pf DHPS shows that 431Vcould alter S436A and A437G.
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Affiliation(s)
- Mary C Oguike
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.
| | - Catherine O Falade
- Department of Pharmacology and Therapeutics, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Elvis Shu
- Department of Pharmacology and Therapeutics, College of Medicine, University of Nigeria, Enugu Campus, Enugu, Nigeria
| | - Izehiuwa G Enato
- Department of Child Health, University of Benin Teaching Hospital, Benin City, Nigeria
| | - Ismaila Watila
- Department of Paediatrics, Specialist Hospital Maiduguri, Borno State, Nigeria
| | - Ebenezer S Baba
- Malaria Consortium, Regional Office for Africa, Kampala, Uganda
| | - Jane Bruce
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jayne Webster
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Daniel Chandramohan
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Colin J Sutherland
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David Warhurst
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Cally Roper
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Fernandes S, Sicuri E, Halimatou D, Akazili J, Boiang K, Chandramohan D, Coulibaly S, Diawara SI, Kayentao K, Ter Kuile F, Magnussen P, Tagbor H, Williams J, Woukeu A, Cairns M, Greenwood B, Hanson K. Cost effectiveness of intermittent screening followed by treatment versus intermittent preventive treatment during pregnancy in West Africa: analysis and modelling of results from a non-inferiority trial. Malar J 2016; 15:493. [PMID: 27663678 PMCID: PMC5035479 DOI: 10.1186/s12936-016-1539-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 09/14/2016] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Emergence of high-grade sulfadoxine-pyrimethamine (SP) resistance in parts of Africa has led to growing concerns about the efficacy of intermittent preventive treatment of malaria during pregnancy (IPTp) with SP. The incremental cost-effectiveness of intermittent screening and treatment (ISTp) with artemether-lumefantrine (AL) as an alternative strategy to IPTp-SP was estimated followed by a simulation of the effects on cost-effectiveness of decreasing efficacy of IPTp-SP due to SP resistance. The analysis was based on results from a multi-centre, non-inferiority trial conducted in West Africa. METHODS A decision tree model was analysed from a health provider perspective. Model parameters for all trial countries with appropriate ranges and distributions were used in a probabilistic sensitivity analysis. Simulations were performed in hypothetical cohorts of 1000 pregnant women who received either ISTp-AL or IPTp-SP. In addition a cost-consequences analysis was conducted. Trial estimates were used to calculate disability-adjusted-life-years (DALYs) for low birth weight and severe/moderate anaemia (both shown to be non-inferior for ISTp-AL) and clinical malaria (inferior for ISTp-AL). Cost estimates were obtained from observational studies, health facility costings and public procurement databases. Results were calculated as incremental cost per DALY averted. Finally, the cost-effectiveness changes with decreasing SP efficacy were explored by simulation. RESULTS Relative to IPTp-SP, delivering ISTp-AL to 1000 pregnant women cost US$ 4966.25 more (95 % CI US$ 3703.53; 6376.83) and led to a small excess of 28.36 DALYs (95 % CI -75.78; 134.18), with LBW contributing 81.3 % of this difference. The incremental cost-effectiveness ratio was -175.12 (95 % CI -1166.29; 1267.71) US$/DALY averted. Simulations show that cost-effectiveness of ISTp-AL increases as the efficacy of IPTp-SP decreases, though the specific threshold at which ISTp-AL becomes cost-effective depends on assumptions about the contribution of bed nets to malaria control, bed net coverage and the willingness-to-pay threshold used. CONCLUSIONS At SP efficacy levels currently observed in the trial settings it would not be cost-effective to switch from IPTp-SP to ISTp-AL, mainly due to the substantially higher costs of ISTp-AL and limited difference in outcomes. The modelling results indicate thresholds below which IPT-SP efficacy must fall for ISTp-AL to become a cost-effective option for the prevention of malaria in pregnancy.
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Affiliation(s)
- Silke Fernandes
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Elisa Sicuri
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Diawara Halimatou
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Dentistry, Malaria Research and Training Centre, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | | | | | - Daniel Chandramohan
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Sheikh Coulibaly
- Faculty of Health Sciences, University of Ouagadougou, Ouagadougou, Burkina Faso
| | - Sory Ibrahim Diawara
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Dentistry, Malaria Research and Training Centre, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Kassoum Kayentao
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Dentistry, Malaria Research and Training Centre, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali.,Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - Pascal Magnussen
- Institute of International Health, Immunology and Microbiology, Centre for Medical Parasitology and Institute of Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - Harry Tagbor
- School of Medicine, University of Health and Allied Sciences, Ho, Ghana
| | | | - Arouna Woukeu
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Matthew Cairns
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Brian Greenwood
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Kara Hanson
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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Kavishe RA, Kaaya RD, Nag S, Krogsgaard C, Notland JG, Kavishe AA, Ishengoma D, Roper C, Alifrangis M. Molecular monitoring of Plasmodium falciparum super-resistance to sulfadoxine-pyrimethamine in Tanzania. Malar J 2016; 15:335. [PMID: 27339129 PMCID: PMC4918075 DOI: 10.1186/s12936-016-1387-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 06/15/2016] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Sulfadoxine-pyrimethamine (SP) is recommended for prophylactic treatment of malaria in pregnancy while artemisinin combination therapy is the recommended first-line anti-malarial treatment. Selection of SP resistance is ongoing since SP is readily available in health facilities and in private drug shops in sub-Saharan Africa. This study reports on the prevalence and distribution of Pfdhps mutations A540E and A581G in Tanzania. When found together, these mutations confer high-level SP resistance (sometimes referred to as 'super-resistance'), which is associated with loss in protective efficacy of SP-IPTp. METHODS DNA samples were extracted from malaria-positive blood samples on filter paper, used malaria rapid diagnostic test strips and whole blood collected from eight sites in seven administrative regions of Tanzania. PCR-RFLP and SSOP-ELISA techniques were used to genotype the A540E and A581G Pfdhps. Data were analysed using SPSS version 18 while Chi square and/or Fischer Exact tests were used to compare prevalence between regions. RESULTS A high inter-regional variation of Pfdhps-540E was observed (χ(2) = 76.8, p < 0.001). High inter-regional variation of 581G was observed (FE = 85.3, p < 0.001). Both Tanga and Kagera were found to have the highest levels of SP resistance. A high prevalence of Pfdhps-581G was observed in Tanga (56.6 %) in northeastern Tanzania and in Kagera (20.4 %) in northwestern Tanzania and the 540-581 EG haplotype was found at 54.5 and 19.4 %, respectively. Pfdhps-581G was not detected in Pwani and Lindi regions located south of Tanga region. CONCLUSIONS Selection of SP super-resistant Pfdhps A581G is highest in northern Tanzania. Variation in distribution of SP resistance is observed across the country: northeastern Tanga region and northwestern Kagera region have highest prevalence of SP super-resistance markers, while in Pwani and Lindi in the southeast the prevalence of super-resistance was zero. More studies should be conducted to understand the factors underlying the remarkable heterogeneity in SP resistance in the country.
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Affiliation(s)
| | - Robert D Kaaya
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Sidsel Nag
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Camilla Krogsgaard
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jakob Ginsbak Notland
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Deus Ishengoma
- National Institute for Medical Research, Tanga Centre, Tanzania
| | - Cally Roper
- London School of Hygiene and Tropical Medicine, London, UK
| | - Michael Alifrangis
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Kakuru A, Jagannathan P, Muhindo MK, Natureeba P, Awori P, Nakalembe M, Opira B, Olwoch P, Ategeka J, Nayebare P, Clark TD, Feeney ME, Charlebois ED, Rizzuto G, Muehlenbachs A, Havlir DV, Kamya MR, Dorsey G. Dihydroartemisinin-Piperaquine for the Prevention of Malaria in Pregnancy. N Engl J Med 2016; 374:928-39. [PMID: 26962728 PMCID: PMC4847718 DOI: 10.1056/nejmoa1509150] [Citation(s) in RCA: 165] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Intermittent treatment with sulfadoxine-pyrimethamine is widely recommended for the prevention of malaria in pregnant women in Africa. However, with the spread of resistance to sulfadoxine-pyrimethamine, new interventions are needed. METHODS We conducted a double-blind, randomized, controlled trial involving 300 human immunodeficiency virus (HIV)-uninfected pregnant adolescents or women in Uganda, where sulfadoxine-pyrimethamine resistance is widespread. We randomly assigned participants to a sulfadoxine-pyrimethamine regimen (106 participants), a three-dose dihydroartemisinin-piperaquine regimen (94 participants), or a monthly dihydroartemisinin-piperaquine regimen (100 participants). The primary outcome was the prevalence of histopathologically confirmed placental malaria. RESULTS The prevalence of histopathologically confirmed placental malaria was significantly higher in the sulfadoxine-pyrimethamine group (50.0%) than in the three-dose dihydroartemisinin-piperaquine group (34.1%, P=0.03) or the monthly dihydroartemisinin-piperaquine group (27.1%, P=0.001). The prevalence of a composite adverse birth outcome was lower in the monthly dihydroartemisinin-piperaquine group (9.2%) than in the sulfadoxine-pyrimethamine group (18.6%, P=0.05) or the three-dose dihydroartemisinin-piperaquine group (21.3%, P=0.02). During pregnancy, the incidence of symptomatic malaria was significantly higher in the sulfadoxine-pyrimethamine group (41 episodes over 43.0 person-years at risk) than in the three-dose dihydroartemisinin-piperaquine group (12 episodes over 38.2 person-years at risk, P=0.001) or the monthly dihydroartemisinin-piperaquine group (0 episodes over 42.3 person-years at risk, P<0.001), as was the prevalence of parasitemia (40.5% in the sulfadoxine-pyrimethamine group vs. 16.6% in the three-dose dihydroartemisinin-piperaquine group [P<0.001] and 5.2% in the monthly dihydroartemisinin-piperaquine group [P<0.001]). In each treatment group, the risk of vomiting after administration of any dose of the study agents was less than 0.4%, and there were no significant differences among the groups in the risk of adverse events. CONCLUSIONS The burden of malaria in pregnancy was significantly lower among adolescent girls or women who received intermittent preventive treatment with dihydroartemisinin-piperaquine than among those who received sulfadoxine-pyrimethamine, and monthly treatment with dihydroartemisinin-piperaquine was superior to three-dose dihydroartemisinin-piperaquine with regard to several outcomes. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT02163447.).
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Affiliation(s)
- Abel Kakuru
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Prasanna Jagannathan
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Mary K Muhindo
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Paul Natureeba
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Patricia Awori
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Miriam Nakalembe
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Bishop Opira
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Peter Olwoch
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - John Ategeka
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Patience Nayebare
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Tamara D Clark
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Margaret E Feeney
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Edwin D Charlebois
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Gabrielle Rizzuto
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Atis Muehlenbachs
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Diane V Havlir
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Moses R Kamya
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
| | - Grant Dorsey
- From the Infectious Diseases Research Collaboration (A.K., M.K.M., P. Natureeba, P.A., B.O., P.O., J.A., P. Nayebare), the Department of Obstetrics and Gynecology, Makerere University College of Health Sciences (M.N.), and the School of Medicine, Makerere University College of Health Sciences (M.R.K.) - all in Kampala, Uganda; the Departments of Medicine (P.J., T.D.C., M.E.F., D.V.H., G.D.), Pediatrics (M.E.F.), and Pathology (G.R.) and the Center for AIDS Prevention Studies (E.D.C.), University of California, San Francisco, San Francisco; and the Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta (A.M.)
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Matangila JR, Mitashi P, Inocêncio da Luz RA, Lutumba PT, Van Geertruyden JP. Efficacy and safety of intermittent preventive treatment for malaria in schoolchildren: a systematic review. Malar J 2015; 14:450. [PMID: 26574017 PMCID: PMC4647321 DOI: 10.1186/s12936-015-0988-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 11/04/2015] [Indexed: 11/10/2022] Open
Abstract
Background Intermittent preventive treatment (IPT) is a proven malaria control strategy in infants and pregnancy. School-aged children represent 26 % of the African population, and an increasing percentage of them are scholarized. Malaria is causing 50 % of deaths in this age group and malaria control efforts may shift the malaria burden to older age groups. Schools have been suggested as a platform for health interventions delivery (deworming, iron-folic acid, nutrients supplementation, (boost-)immunization) and as a possible delivery system for IPT in schoolchildren (IPTsc). However, the current evidence on the efficacy and safety of IPTsc is limited and the optimal therapeutic regimen remains controversial. Methods A systematic search for studies reporting efficacy and safety of IPT in schoolchildren was conducted using PubMed, Web of Science, Clinicaltrials and WHO/ICTRP database, and abstracts from congresses with the following key words: intermittent, preventive treatment AND malaria OR Plasmodium falciparum AND schoolchildren NOT infant NOT pregnancy. Results Five studies were identified. Most IPTsc regimes demonstrated substantial protection against malaria parasitaemia, with dihydroartemisinin-piperaquine (DP) given monthly having the highest protective effect (PE) (94 %; 95 % CI 93–96). Contrarily, SP did not provide any PE against parasitaemia. However, no IPT regimen provided a PE above 50 % in regard to anaemia, and highest protection was provided by SP+ amodiaquine (AQ) given four-monthly (50 %; 95 % CI 41–53). The best protection against clinical malaria was observed in children monthly treated with DP (97 %; 95 % CI 87–98). However, there was no protection when the drug was given three-monthly. No severe adverse events were associated with the drugs used for IPTsc. Conclusion IPTsc may reduce the malaria-related burden in schoolchildren. However, more studies assessing efficacy of IPT in particular against malaria-related anaemia and clinical malaria in schoolchildren must be conducted.
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Affiliation(s)
- Junior R Matangila
- Département de Médecine Tropicale, Faculté de Médecine, Université de Kinshasa, BP 747, Kinshasa, XI, Democratic Republic of the Congo. .,Epidemiology for Global Health Institute, University of Antwerp, Campus DrieEiken, Universiteitsplein 1, Wilrijk, 2610, Belgium.
| | - Patrick Mitashi
- Département de Médecine Tropicale, Faculté de Médecine, Université de Kinshasa, BP 747, Kinshasa, XI, Democratic Republic of the Congo.
| | - Raquel A Inocêncio da Luz
- Epidemiology for Global Health Institute, University of Antwerp, Campus DrieEiken, Universiteitsplein 1, Wilrijk, 2610, Belgium.
| | - Pascal T Lutumba
- Département de Médecine Tropicale, Faculté de Médecine, Université de Kinshasa, BP 747, Kinshasa, XI, Democratic Republic of the Congo.
| | - Jean-Pierre Van Geertruyden
- Epidemiology for Global Health Institute, University of Antwerp, Campus DrieEiken, Universiteitsplein 1, Wilrijk, 2610, Belgium.
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Muanda FT, Chaabane S, Boukhris T, Santos F, Sheehy O, Perreault S, Blais L, Bérard A. Antimalarial drugs for preventing malaria during pregnancy and the risk of low birth weight: a systematic review and meta-analysis of randomized and quasi-randomized trials. BMC Med 2015; 13:193. [PMID: 26275820 PMCID: PMC4537579 DOI: 10.1186/s12916-015-0429-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/17/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND It is known that antimalarial drugs reduce the risk of low birth weight (LBW) in pregnant patients. However, a previous Cochrane review did not evaluate whether the level of antimalarial drug resistance could modify the protective effect of antimalarial drugs in this regard. In addition, no systematic review exists comparing current recommendations for malaria prevention during pregnancy to alternative regimens in Africa. Therefore, we conducted a comprehensive systematic review and meta-analysis to assess the efficacy of antimalarial drugs for malaria prevention during pregnancy in reducing the risk of LBW. METHODS We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) for articles published up to 21 November 2014, in English or French, and identified additional studies from reference lists. We included randomized and quasi-randomized studies reporting LBW as one of the outcomes. We extracted data and assessed the risk of bias in selected studies. All pooled analyses were based on a random effect model, and we used a funnel plot and trim and fill method to test and adjust for publication bias. RESULTS A total of 25 studies met the inclusion criteria (37,981 subjects). Compared to no use, all combined antimalarial drugs were associated with a 27% (RR 0.73, 95% CI 0.56-0.97, ten studies) reduction in the risk of LBW. The level of antimalarial drug resistance modified the protective effect of the antimalarial drug used for prevention of LBW during pregnancy. Sulfadoxine-pyrimethamine was not associated with a reduction in the risk of LBW in regions where the prevalence of the dihydropteroate synthase 540E mutation exceeds 50% (RR 0.99, 95% CI 0.80-1.22, three studies). The risk of LBW was similar when sulfadoxine-pyrimethamine was compared to mefloquine (RR 1.05, 95% CI 0.86-1.29, two studies). CONCLUSION Prophylactic antimalarial drugs and specifically sulfadoxine-pyrimethamine may no longer protect against the risk of LBW in areas of high-level resistance. In Africa, there are currently no suitable alternative drugs to replace sulfadoxine-pyrimethamine for malaria prevention during pregnancy.
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Affiliation(s)
- Flory Tsobo Muanda
- Faculty of Pharmacy, University of Montreal, 2940 Chemin de Polytechnique, Montreal, QC, H3T 1J4, Canada. .,Research Center, CHU Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
| | - Sonia Chaabane
- Faculty of Pharmacy, University of Montreal, 2940 Chemin de Polytechnique, Montreal, QC, H3T 1J4, Canada. .,Research Center, CHU Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
| | - Takoua Boukhris
- Faculty of Pharmacy, University of Montreal, 2940 Chemin de Polytechnique, Montreal, QC, H3T 1J4, Canada. .,Research Center, CHU Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
| | - Fabiano Santos
- Faculty of Medicine, McGill University, 3605 Rue de la Montagne, Montreal, QC, H3G 2M1, Canada.
| | - Odile Sheehy
- Research Center, CHU Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
| | - Sylvie Perreault
- Faculty of Pharmacy, University of Montreal, 2940 Chemin de Polytechnique, Montreal, QC, H3T 1J4, Canada.
| | - Lucie Blais
- Faculty of Pharmacy, University of Montreal, 2940 Chemin de Polytechnique, Montreal, QC, H3T 1J4, Canada.
| | - Anick Bérard
- Faculty of Pharmacy, University of Montreal, 2940 Chemin de Polytechnique, Montreal, QC, H3T 1J4, Canada. .,Research Center, CHU Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
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Chauvin P, Menard S, Iriart X, Nsango SE, Tchioffo MT, Abate L, Awono-Ambéné PH, Morlais I, Berry A. Prevalence of Plasmodium falciparum parasites resistant to sulfadoxine/pyrimethamine in pregnant women in Yaoundé, Cameroon: emergence of highly resistant pfdhfr/pfdhps alleles. J Antimicrob Chemother 2015; 70:2566-71. [PMID: 26080363 DOI: 10.1093/jac/dkv160] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 05/22/2015] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES To determine, 6 years after the adoption of intermittent preventive treatment of pregnant women with sulfadoxine/pyrimethamine (IPTp-SP) in Cameroon, (i) the polymorphism and prevalence of Plasmodium falciparum dihydrofolate reductase (pfdhfr) and dihydropteroate synthase (pfdhps) gene mutations associated with sulfadoxine/pyrimethamine resistance and (ii) the consequences of sulfadoxine/pyrimethamine use in the selection of pfdhfr/pfdhps alleles. METHODS pfdhfr and pfdhps genes from P. falciparum isolates collected in Yaoundé (Cameroon) from pregnant women with symptomatic malaria before taking IPTp-SP [SP- group (control) (n = 51)] or afterwards [SP+ group (n = 49)] were sequenced. RESULTS The pfdhfr N51I, C59R, S108N triple mutant had a prevalence close to 100% (96/100) and no mutations at codons 50 and 164 were detected in either of the groups. The most frequent pfdhps mutation was A437G with a prevalence of 76.5% (39/51) in the SP- group, which was significantly higher in pregnant women who took sulfadoxine/pyrimethamine [95.9% (47/49)] (P = 0.012). Our study confirmed the presence of the pfdhps K540E mutation in Cameroon, but it remained rare. The prevalence of pfdhps A581G and A613S mutations had increased [5.9% (3/51) and 11.8% (6/51) in the control group, respectively] since the last studies in 2005. Surprisingly, the new pfdhps I431V mutation was detected, at a prevalence of 9.8% (5/51), and was found to be associated with other pfdhfr/pfdhps alleles to form an octuple N51I, C59R, S108N/I431V, S436A, A437G, A581G, A613S mutant. CONCLUSIONS Significant changes were found in pfdhps polymorphism. In particular, we observed several parasites carrying eight mutations in pfdhfr/pfdhps genes, which are very susceptible to having a high level of resistance to sulfadoxine/pyrimethamine.
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Affiliation(s)
- Pamela Chauvin
- Service de Parasitologie-Mycologie, CHU Toulouse, Toulouse, France
| | - Sandie Menard
- Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, CNRS UMR5282, Université de Toulouse, Toulouse, France
| | - Xavier Iriart
- Service de Parasitologie-Mycologie, CHU Toulouse, Toulouse, France Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, CNRS UMR5282, Université de Toulouse, Toulouse, France
| | - Sandrine E Nsango
- Faculté de Médecine et des Sciences Pharmaceutiques, Université de Douala, Douala, Cameroon Laboratoire d'Entomologie Médicale, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale, Yaoundé, Cameroon
| | - Majoline T Tchioffo
- Laboratoire d'Entomologie Médicale, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale, Yaoundé, Cameroon UMR MIVEGEC, IRD, 224-CNR, 5290-UM1-UM2, Institut de Recherche pour le Développement, Montpellier, France
| | - Luc Abate
- UMR MIVEGEC, IRD, 224-CNR, 5290-UM1-UM2, Institut de Recherche pour le Développement, Montpellier, France
| | - Parfait H Awono-Ambéné
- Laboratoire d'Entomologie Médicale, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale, Yaoundé, Cameroon
| | - Isabelle Morlais
- Laboratoire d'Entomologie Médicale, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale, Yaoundé, Cameroon UMR MIVEGEC, IRD, 224-CNR, 5290-UM1-UM2, Institut de Recherche pour le Développement, Montpellier, France
| | - Antoine Berry
- Service de Parasitologie-Mycologie, CHU Toulouse, Toulouse, France Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, CNRS UMR5282, Université de Toulouse, Toulouse, France
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Iwalokun BA, Iwalokun SO, Adebodun V, Balogun M. Carriage of Mutant Dihydrofolate Reductase and Dihydropteroate Synthase Genes among Plasmodium falciparum Isolates Recovered from Pregnant Women with Asymptomatic Infection in Lagos, Nigeria. Med Princ Pract 2015; 24:436-43. [PMID: 26202938 PMCID: PMC5588254 DOI: 10.1159/000430987] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 04/28/2015] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To assess N51I, C59R and S108N polymorphisms of dihydrofolate reductase (dhfr) and A437G and K540E of dihydropteroate synthase (dhps) genes of P. falciparum isolates recovered from pregnant women with asymptomatic malaria in a coastal setting in Nigeria. SUBJECTS AND METHODS A total of 107 consenting and consecutively enrolled pregnant women (mean age ± standard deviation, 26.6 ± 4.5 years) attending antenatal care at the Iru/Victoria Island Primary Health Centre, Lagos, were screened for peripheral malaria by microscopy, by a histidine-rich protein-2-based rapid diagnostic test (RDT) and by polymerase chain reaction (PCR) using finger-pricked and dot blood samples. DNA was extracted from the blood and used for dhfr and dhps gene polymorphism analyses by PCR and restriction fragment length polymorphism. The sociodemographic and parasite data obtained were analysed. RESULTS Of the 107 patients, 34 (31.8%), 46 (43%) and 40 (37.4%) were found to be P. falciparum infected using microscopy, RDT and corrected RDT-PCR, respectively (p < 0.05). The prevalence of P. falciparum isolates with mutant and mixed genotypes of dhfr at codons 51, 59 and 108 was 70, 75 and 80%, respectively, and the triple mutation in the homozygous form was 35%. The prevalence of the homozygous quintuple dhfr plus dhps mutant was 5%, while that of the P. falciparum isolates with mutant or mixed genotypes of dhps at codons 437 and 540 was 37.5 and 22.5%, respectively. CONCLUSION This study revealed the emergence of the K540E mutation among the parasite population in Lagos. However, it supports the implementation of the intermittent preventive treatment of malaria during pregnancy with sulphadoxine-pyrimethamine with continuous effectiveness monitoring in the study area.
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Affiliation(s)
- Bamidele Abiodun Iwalokun
- Department of Biochemistry and Nutrition, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria
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Bigira V, Kapisi J, Clark TD, Kinara S, Mwangwa F, Muhindo MK, Osterbauer B, Aweeka FT, Huang L, Achan J, Havlir DV, Rosenthal PJ, Kamya MR, Dorsey G. Protective efficacy and safety of three antimalarial regimens for the prevention of malaria in young Ugandan children: a randomized controlled trial. PLoS Med 2014; 11:e1001689. [PMID: 25093754 PMCID: PMC4122345 DOI: 10.1371/journal.pmed.1001689] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 06/26/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Chemoprevention offers a promising strategy for prevention of malaria in African children. However, the optimal chemoprevention drug and dosing strategy is unclear in areas of year-round transmission and resistance to many antimalarial drugs. To compare three available regimens, we conducted an open-label randomized controlled trial of chemoprevention in Ugandan children. METHODS AND FINDINGS This study was conducted between June 28, 2010, and September 25, 2013. 400 infants were enrolled and 393 randomized at 6 mo of age to no chemoprevention, monthly sulfadoxine-pyrimethamine (SP), daily trimethoprim-sulfamethoxazole (TS), or monthly dihydroartemisinin-piperaquine (DP). Study drugs were administered at home without supervision. Piperaquine (PQ) levels were used as a measure of compliance in the DP arm. Participants were given insecticide-treated bednets, and caregivers were encouraged to bring their child to a study clinic whenever they were ill. Chemoprevention was stopped at 24 mo of age, and participants followed-up an additional year. Primary outcome was the incidence of malaria during the intervention period. During the intervention, the incidence of malaria in the no chemoprevention arm was 6.95 episodes per person-year at risk. Protective efficacy was 58% (95% CI, 45%-67%, p<0.001) for DP, 28% (95% CI, 7%-44%, p = 0.01) for TS, and 7% for SP (95% CI, -19% to 28%, p = 0.57). PQ levels were below the detection limit 52% of the time when malaria was diagnosed in the DP arm, suggesting non-adherence. There were no differences between the study arms in the incidence of serious adverse events during the intervention and the incidence of malaria during the 1-y period after the intervention was stopped. CONCLUSIONS For preventing malaria in children living in an area of high transmission intensity, monthly DP was the most efficacious and safe, although adherence may pose a problem. Monthly SP and daily TS may not be appropriate in areas with high transmission intensity and frequent resistance to antifolates. TRIAL REGISTRATION www.ClinicalTrials.gov NCT00948896 Please see later in the article for the Editors' Summary.
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Affiliation(s)
- Victor Bigira
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - James Kapisi
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Tamara D. Clark
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Stephen Kinara
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | - Beth Osterbauer
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Francesca T. Aweeka
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Liusheng Huang
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Jane Achan
- Department of Pediatrics, Makerere University College of Health Sciences, Kampala, Uganda
| | - Diane V. Havlir
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Philip J. Rosenthal
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
| | - Moses R. Kamya
- Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, United States of America
- * E-mail:
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Duvignaud A, Denoeud-Ndam L, Akakpo J, Agossou KV, Afangnihoun A, Komongui DG, Atadokpédé F, Dossou-Gbété L, Girard PM, Zannou DM, Cot M. Incidence of malaria-related fever and morbidity due to Plasmodium falciparum among HIV1-infected pregnant women: a prospective cohort study in South Benin. Malar J 2014; 13:255. [PMID: 24996807 PMCID: PMC4089929 DOI: 10.1186/1475-2875-13-255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 06/30/2014] [Indexed: 11/28/2022] Open
Abstract
Background Malaria and HIV are two major causes of morbidity and mortality among pregnant women in sub-Saharan Africa. Foetal and neonatal outcomes of this co-infection have been extensively studied. However, little is known about maternal morbidity due to clinical malaria in pregnancy, especially malaria-related fever, in the era of generalized access to antiretroviral therapy and anti-malarial preventive strategies. Methods A cohort study was conducted in order to estimate the incidence rate and to determine the factors associated with malaria-related fever, as well as the maternal morbidity attributable to malaria in a high-transmission setting of South Benin among HIV-infected pregnant women. Four-hundred and thirty-two women who participated in a randomized trial testing strategies to prevent malaria in pregnancy were included and followed until delivery, with at least three scheduled visits during pregnancy. Confirmed malaria-related fever was defined as axillary temperature >37.5°C and a concomitant, positive, thick blood smear or rapid diagnostic test for Plasmodium falciparum. Suspected malaria-related fever was defined as an axillary temperature >37.5°C and the concomitant administration of an anti-malarial treatment in the absence of parasitological investigation. Results Incidence rate for confirmed malaria-related fever was of 127.9 per 1,000 person-year (PY) (95% confidence interval (CI): 77.4-211.2). In multivariate analysis, CD4 lymphocytes (Relative Risk (RR) for a 50 cells/mm3 variation = 0.82; CI: 0.71-0.96), antiretroviral treatment started before inclusion (RR = 0.34; CI: 0.12-0.98) and history of symptomatic malaria in early pregnancy (RR = 7.10; CI: 2.35-22.49) were associated with the incidence of confirmed or suspected malaria-related fever. More than a half of participants with parasitaemia were symptomatic, with fever being the most common symptom. The crude fraction of febrile episodes attributable to malaria was estimated at 91%. Conclusions This work highlights that malaria is responsible for a substantial morbidity in HIV-infected pregnant women, with cellular immunodepression as a major determinant, and establishes the possible advantage offered by the early initiation of antiretroviral treatment. Trial registration PACOME Study has been registered under the number NCT00970879.
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Coulibaly SO, Kayentao K, Taylor S, Guirou EA, Khairallah C, Guindo N, Djimde M, Bationo R, Soulama A, Dabira E, Barry B, Niangaly M, Diakite H, Konate S, Keita M, Traore B, Meshnick SR, Magnussen P, Doumbo OK, ter Kuile FO. Parasite clearance following treatment with sulphadoxine-pyrimethamine for intermittent preventive treatment in Burkina-Faso and Mali: 42-day in vivo follow-up study. Malar J 2014; 13:41. [PMID: 24484467 PMCID: PMC3914849 DOI: 10.1186/1475-2875-13-41] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 01/28/2014] [Indexed: 11/21/2022] Open
Abstract
Background Intermittent Preventive Treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) is widely used for the control of malaria in pregnancy in Africa. The emergence of resistance to SP is a concern requiring monitoring the effectiveness of SP for IPTp. Methods This was an in-vivo efficacy study to determine the parasitological treatment response and the duration of post-treatment prophylaxis among asymptomatic pregnant women receiving SP as part of IPTp in Mali and Burkina-Faso. The primary outcome was the PCR-unadjusted % of patients with parasites recurrence by day 42 defined as a positive diagnostic test by malaria smear at any visit between days 4 and 42. Treatment failure was based on the standard World Health Organization criteria. The therapeutic response was estimated using the Kaplan-Meier curve. Results A total of 580 women were enrolled in Mali (N=268) and Burkina-Faso (N=312) and followed weekly for 42 days. Among these, 94.3% completed the follow-up. The PCR-unadjusted cumulative risk of recurrence by day 42 was 4.9% overall, and 3.2% and 6.5% in Mali and Burkina Faso respectively (Hazard Ratio [HR] =2.14, 95%, CI [0.93-4.90]; P=0.070), and higher among the primi– and secundigravida (6.4%) than multigravida (2.2%, HR=3.01 [1.04-8.69]; P=0.042). The PCR-adjusted failure risk was 1.1% overall (Mali 0.8%, Burkina-Faso 1.4%). The frequencies (95% CI) of the dhfr double and triple mutant and dhps 437 and 540 alleles mutant genotype at enrolment were 24.2% (23.7-25.0), 4.7% (4.4-5.0), and 21.4% (20.8-22.0) and 0.37% (0.29-0.44) in Mali, and 7.1% (6.5-7.7), 44.9% (43.8-46.0) and 75.3% (74.5-76.2) and 0% in Burkina-Faso, respectively. There were no dhfr 164L or dhps 581G mutations. Conclusion SP remains effective at clearing existing infections when provided as IPTp to asymptomatic pregnant women in Mali and Burkina. Continued monitoring of IPTp-SP effectiveness, including of the impact on birth parameters in this region is essential.
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Affiliation(s)
| | - Kassoum Kayentao
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Center, Faculty of Medicine and Odonto-stomatology of Bamako, University of Sciences, Technics and Technologies, BP: 1805, Bamako, Mali.
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Progress in paediatric parasitology: a preface to a topic focusing on ever younger subjects. Parasitology 2014; 138:1453-8. [PMID: 21923961 DOI: 10.1017/s0031182011001545] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Without realizing it perhaps, the research activities of many parasitologists are often focused upon the study of parasites most commonly found in children. Though there is little recognition of paediatric parasitology as a separate topic within medical parasitology, with the global interest in promotion of maternal and child health, alleviation of diseases associated with poverty and requirements of 'child-sized' medicines, a more formal consideration is now timely. Recent research, for example, has highlighted that defining precisely the 'first-age' at which parasites interfere with a child's health, or normal developmental processes, is being revised. Attention is now drawn towards ever younger subjects, for parasites have the capacity to also influence the health of the foetus within the in utero environment, altering immune-development. These subtle, yet evolutionary profound interactions perhaps manifest themselves as to why some children are more prone to infection(s), develop overt disease and sadly die while others do not. Here, we address the growing importance of paediatric parasitology and its applications within disease control strategies as highlighted in the 2010 Autumn Symposium of the British Society of Parasitology.
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Mapping 'partially resistant', 'fully resistant', and 'super resistant' malaria. Trends Parasitol 2013; 29:505-15. [PMID: 24028889 DOI: 10.1016/j.pt.2013.08.002] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 08/12/2013] [Accepted: 08/12/2013] [Indexed: 11/24/2022]
Abstract
Sulfadoxine-pyrimethamine (SP) is used throughout Africa for intermittent preventive treatment (IPT) of malaria, but resistance threatens its efficacy. We found marked regional differences in the genotypes responsible for SP resistance when mapping recent surveys of dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) mutations. In West Africa, a 'partially resistant' combination of dhfr N51I, N59R, and S108N with dhps A437G predominates, whereas in East Africa the 'fully resistant' combination of dhfr N51I, N59R, and S108N with dhps A437G+K540E is found. There are three East African foci where 'fully resistant' populations have additionally acquired dhps 581G and/or dhfr 164L to become 'super resistant'. SP-IPT in infants and pregnant women is reported to have failed in super resistant areas prompting review of SP-IPT use in affected areas.
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Flegg JA, Metcalf CJE, Gharbi M, Venkatesan M, Shewchuk T, Hopkins Sibley C, Guerin PJ. Trends in antimalarial drug use in Africa. Am J Trop Med Hyg 2013; 89:857-865. [PMID: 24019436 PMCID: PMC3820326 DOI: 10.4269/ajtmh.13-0129] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Resistance to chloroquine (CQ) and sulphadoxine-pyrimethamine (SP) led the World Health Organization (WHO) to recommend changes in national drug policies. The time between policy changes and their implementation profoundly affects program impact. We developed a model based on data on antimalarial treatments, extracted from household surveys and national antimalarial policy information from the literature. Drug use in each country during the time period 1999–2011 and the trend in reduction of CQ use after policy change were estimated. The SP use estimates were correlated with the prevalence of a molecular marker associated with SP resistance. There was no spatial pattern in the country-level rate of reduction of CQ use, after policy change. In East Africa SP drug use was strongly correlated to resistance. If artemisinin resistance spreads to, or emerges in, Africa this methodology will be a valuable tool to estimate actual drug use and its impact on changes in drug efficacy.
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Affiliation(s)
- Jennifer A. Flegg
- *Address correspondence to Jennifer A. Flegg, Centre for Tropical Medicine, University of Oxford, CCVTM, Churchill Hospital, Old Road, Oxford, OX3 7LJ, UK. E-mail:
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Arinaitwe E, Ades V, Walakira A, Ninsiima B, Mugagga O, Patil TS, Schwartz A, Kamya MR, Nasr S, Chang M, Filler S, Dorsey G. Intermittent preventive therapy with sulfadoxine-pyrimethamine for malaria in pregnancy: a cross-sectional study from Tororo, Uganda. PLoS One 2013; 8:e73073. [PMID: 24023811 PMCID: PMC3762885 DOI: 10.1371/journal.pone.0073073] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 07/17/2013] [Indexed: 11/19/2022] Open
Abstract
Background Intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is widely recommended in sub-Saharan Africa to reduce the risk of malaria and improve birth outcomes. However, there are reports that the efficacy of IPTp with SP is waning, especially in parts of Africa where antimalarial resistance to this drug has become widespread. Methodology/Principal Findings We conducted a cross-sectional study of 565 HIV-uninfected women giving birth at Tororo District Hospital in southeastern Uganda. The primary objective of the study was to measure associations between use of SP during pregnancy from antenatal records and the risk of adverse outcomes including placental malaria, low birth weight, maternal parasitemia and maternal anemia. The proportion of women who reported taking 0, 1, 2, and 3 doses of SP during pregnancy was 5.7%, 35.8%, 56.6% and 2.0% respectively. Overall, the prevalence of placental malaria was 17.5%, 28.1%, and 66.2% by placental smear, PCR, and histopathology, respectively. In multivariate analyses controlling for potential confounders, ≥2 doses of SP was associated with non-significant trends towards lower odds of placental malaria by placental smear (OR = 0.75, p = 0.25), placental malaria by PCR (OR = 0.93, p = 0.71), placental malaria by histopathology (OR = 0.75, p = 0.16), low birth weight (OR = 0.63, p = 0.11), maternal parasitemia (OR = 0.88, p = 0.60) and maternal anemia (OR = 0.88, p = 0.48). Using a composite outcome, ≥2doses of SP was associated with a significantly lower odds of placental malaria, low birth weight, maternal parasitemia, or maternal anemia (OR = 0.52, p = 0.01). Conclusions/Significance In this area of Uganda with intense malaria transmission, the prevalence of placental malaria by histopathology was high even among women who reported taking at least 2 doses of SP during pregnancy. The reported use of ≥2 doses of SP was not associated with protection against individual birth and maternal outcome measures but did protect against a composite measure of any adverse outcome.
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Affiliation(s)
| | - Veronica Ades
- Department of Obstetrics, Gynecology & Reproductive Sciences, University of California San Francisco, San Francisco, California, United States of America
| | | | - Boaz Ninsiima
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Olive Mugagga
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Teja S. Patil
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Alanna Schwartz
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Moses R. Kamya
- Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Sussann Nasr
- Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Michelle Chang
- Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Scott Filler
- The Global Fund to Fight Acquired Immune Deficiency Syndrome, Tuberculosis, and Malaria, Geneva, Switzerland
| | - Grant Dorsey
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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Ndiaye D, Dieye B, Ndiaye YD, Van Tyne D, Daniels R, Bei AK, Mbaye A, Valim C, Lukens A, Mboup S, Ndir O, Wirth DF, Volkman S. Polymorphism in dhfr/dhps genes, parasite density and ex vivo response to pyrimethamine in Plasmodium falciparum malaria parasites in Thies, Senegal. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2013; 3:135-42. [PMID: 24533303 PMCID: PMC3862402 DOI: 10.1016/j.ijpddr.2013.07.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/19/2013] [Accepted: 07/21/2013] [Indexed: 11/14/2022]
Abstract
Prevalence of dhfr/dhps mutations increased significantly between 2003 and 2011. Triple mutant dhfr 51I/59R/108N increased, from 40% in 2003 to 93% in 2011. Quadruple mutant dhfr and dhps 437G increased, from 20% to 66% then down. A strong correlation between ex vivo response to pyrimethamine and dhfr genotype.
Resistance to sulfadoxine–pyrimethamine (SP) in Plasmodium falciparum malaria parasites is associated with mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes, and these mutations have spread resistance worldwide. SP, used for several years in Senegal, has been recommended for intermittent preventive treatment for malaria in pregnancy (IPTp) and has been widely implemented since 2003 in this country. There is currently limited data on SP resistance from molecular marker genotyping, and no data on pyrimethamine ex vivo sensitivity in Senegal. Molecular markers of SP resistance and pyrimethamine ex vivo sensitivity were investigated in 416 parasite samples collected from the general population, from the Thies region between 2003 and 2011. The prevalence of the N51I/C59R/S108N triple mutation in dhfr increased from 40% in 2003 to 93% in 2011. Furthermore, the prevalence of the dhfr N51I/C59R/S108N and dhps A437G quadruple mutation increased, from 20% to 66% over the same time frame, then down to 44% by 2011. There was a significant increase in the prevalence of the dhfr triple mutation, as well as an association between dhfr genotypes and pyrimethamine response. Conversely, dhps mutations in codons 436 and 437 did not show consistent variation between 2003 and 2011. These findings suggest that regular screening for molecular markers of antifolate resistance and ex vivo drug response monitoring should be incorporated with ongoing in vivo efficacy monitoring in areas where IPTp-SP is implemented and where pyrimethamine and sulfa drugs are still widely administered in the general population.
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Affiliation(s)
- Daouda Ndiaye
- Faculty of Medicine and Pharmacy, University Cheikh Anta Diop, Dakar, PO Box 5005, Dakar, Senegal
| | - Baba Dieye
- Faculty of Medicine and Pharmacy, University Cheikh Anta Diop, Dakar, PO Box 5005, Dakar, Senegal
| | - Yaye D Ndiaye
- Faculty of Medicine and Pharmacy, University Cheikh Anta Diop, Dakar, PO Box 5005, Dakar, Senegal
| | - Daria Van Tyne
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
| | - Rachel Daniels
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
| | - Amy K Bei
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
| | - Aminata Mbaye
- Faculty of Medicine and Pharmacy, University Cheikh Anta Diop, Dakar, PO Box 5005, Dakar, Senegal
| | - Clarissa Valim
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
| | - Amanda Lukens
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
| | - Souleymane Mboup
- Faculty of Medicine and Pharmacy, University Cheikh Anta Diop, Dakar, PO Box 5005, Dakar, Senegal
| | - Omar Ndir
- Faculty of Medicine and Pharmacy, University Cheikh Anta Diop, Dakar, PO Box 5005, Dakar, Senegal
| | - Dyann F Wirth
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
| | - Sarah Volkman
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA
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Venkatesan M, Alifrangis M, Roper C, Plowe CV. Monitoring antifolate resistance in intermittent preventive therapy for malaria. Trends Parasitol 2013; 29:497-504. [PMID: 23948432 DOI: 10.1016/j.pt.2013.07.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 07/18/2013] [Accepted: 07/19/2013] [Indexed: 10/26/2022]
Abstract
Mutations in the Plasmodium falciparum genes Pfdhfr and Pfdhps have rendered sulfadoxine-pyrimethamine (SP) ineffective for malaria treatment in most regions of the world. Yet, SP is efficacious as intermittent preventive therapy in pregnant women (IPTp) and infants (IPTi) and as seasonal malaria control in children (SMC). SP-IPTp is being widely implemented in sub-Saharan Africa. SP-IPTi is recommended where the prevalence of SP-resistant malaria parasites is low, whereas SMC is recommended for areas of intense seasonal malaria transmission. The continuing success of these interventions depends largely on the prevalence of Pfdhfr and Pfdhps resistance mutations in the target population. Here we review the relationship between resistance mutations and SP-IPT within target populations in the context of monitoring and informing implementation of this intervention.
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Affiliation(s)
- Meera Venkatesan
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, 685 West Baltimore Street, HSF1-480, Baltimore, MD 21201, USA; WorldWide Antimalarial Resistance Network (WWARN) Molecular Module(*)
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Spatiotemporal mathematical modelling of mutations of the dhps gene in African Plasmodium falciparum. Malar J 2013; 12:249. [PMID: 23866695 PMCID: PMC3728261 DOI: 10.1186/1475-2875-12-249] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/02/2013] [Indexed: 11/28/2022] Open
Abstract
Background Plasmodium falciparum has repeatedly evolved resistance to first-line anti-malarial drugs, thwarting efforts to control and eliminate the disease and in some period of time this contributed largely to an increase in mortality. Here a mathematical model was developed to map the spatiotemporal trends in the distribution of mutations in the P. falciparum dihydropteroate synthetase (dhps) gene that confer resistance to the anti-malarial sulphadoxine, and are a useful marker for the combination of alleles in dhfr and dhps that is highly correlated with resistance to sulphadoxine-pyrimethamine (SP). The aim of this study was to present a proof of concept for spatiotemporal modelling of trends in anti-malarial drug resistance that can be applied to monitor trends in resistance to components of artemisinin combination therapy (ACT) or other anti-malarials, as they emerge or spread. Methods Prevalence measurements of single nucleotide polymorphisms in three codon positions of the dihydropteroate synthetase (dhps) gene from published studies of dhps mutations across Africa were used. A model-based geostatistics approach was adopted to create predictive surfaces of the dhps540E mutation over the spatial domain of sub-Saharan Africa from 1990-2010. The statistical model was implemented within a Bayesian framework and hence quantified the associated uncertainty of the prediction of the prevalence of the dhps540E mutation in sub-Saharan Africa. Conclusions The maps presented visualize the changing prevalence of the dhps540E mutation in sub-Saharan Africa. These allow prediction of space-time trends in the parasite resistance to SP, and provide probability distributions of resistance prevalence in places where no data are available as well as insight on the spread of resistance in a way that the data alone do not allow. The results of this work will be extended to design optimal sampling strategies for the future molecular surveillance of resistance, providing a proof of concept for similar techniques to design optimal strategies to monitor resistance to ACT.
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