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Manzoni G, Try R, Guintran JO, Christiansen-Jucht C, Jacoby E, Sovannaroth S, Zhang Z, Banouvong V, Shortus MS, Reyburn R, Chanthavisouk C, Linn NYY, Thapa B, Khine SK, Sudathip P, Gopinath D, Thieu NQ, Ngon MS, Cong DT, Hui L, Kelley J, Valecha NNK, Bustos MD, Rasmussen C, Tuseo L. Progress towards malaria elimination in the Greater Mekong Subregion: perspectives from the World Health Organization. Malar J 2024; 23:64. [PMID: 38429807 PMCID: PMC10908136 DOI: 10.1186/s12936-024-04851-z] [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: 11/09/2023] [Accepted: 01/11/2024] [Indexed: 03/03/2024] Open
Abstract
Malaria remains a global health challenge, disproportionately affecting vulnerable communities. Despite substantial progress, the emergence of anti-malarial drug resistance poses a constant threat. The Greater Mekong Subregion (GMS), which includes Cambodia, China's Yunnan province, Lao People's Democratic Republic, Myanmar, Thailand, and Viet Nam has been the epicentre for the emergence of resistance to successive generations of anti-malarial therapies. From the perspective of the World Health Organization (WHO), this article considers the collaborative efforts in the GMS, to contain Plasmodium falciparum artemisinin partial resistance and multi-drug resistance and to advance malaria elimination. The emergence of artemisinin partial resistance in the GMS necessitated urgent action and regional collaboration resulting in the Strategy for Malaria Elimination in the Greater Mekong Subregion (2015-2030), advocating for accelerated malaria elimination interventions tailored to country needs, co-ordinated and supported by the WHO Mekong malaria elimination programme. The strategy has delivered substantial reductions in malaria across all GMS countries, with a 77% reduction in malaria cases and a 97% reduction in malaria deaths across the GMS between 2012 and 2022. Notably, China was certified malaria-free by WHO in 2021. Countries' ownership and accountability have been pivotal, with each GMS country outlining its priorities in strategic and annual work plans. The development of strong networks for anti-malarial drug resistance surveillance and epidemiological surveillance was essential. Harmonization of policies and guidelines enhanced collaboration, ensuring that activities were driven by evidence. Challenges persist, particularly in Myanmar, where security concerns have limited recent progress, though an intensification and acceleration plan aims to regain momentum. Barriers to implementation can slow progress and continuing innovation is needed. Accessing mobile and migrant populations is key to addressing remaining transmission foci, requiring effective cross-border collaboration. In conclusion, the GMS has made significant progress towards malaria elimination, particularly in the east where several countries are close to P. falciparum elimination. New and persisting challenges require sustained efforts and continued close collaboration. The GMS countries have repeatedly risen to every obstacle presented, and now is the time to re-double efforts and achieve the 2030 goal of malaria elimination for the region.
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Affiliation(s)
- Giulia Manzoni
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia.
- Independent Consultant, Antananarivo, Madagascar.
| | - Rady Try
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia
| | - Jean Olivier Guintran
- World Health Organization Country Office, Phnom Penh, Cambodia
- Independent Consultant, Le Bar sur Loup, France
| | | | - Elodie Jacoby
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia
- Independent Consultant, Ho Chi Minh, Viet Nam
| | - Siv Sovannaroth
- National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Zaixing Zhang
- World Health Organization Country Office, Phnom Penh, Cambodia
| | | | | | - Rita Reyburn
- World Health Organization Country Office, Vientiane, Lao PDR
| | | | - Nay Yi Yi Linn
- National Malaria Control Programme, Nay Pyi Taw, Myanmar
| | - Badri Thapa
- World Health Organization Country Office, Yangon, Myanmar
| | | | - Prayuth Sudathip
- Division of Vector Borne Diseases, Department of Disease Control, Bangkok, Thailand
| | - Deyer Gopinath
- World Health Organization Country Office, Bangkok, Thailand
| | - Nguyen Quang Thieu
- National Institute of Malariology, Parasitology and Entomology, Hanoi, Viet Nam
| | | | | | - Liu Hui
- Yunnan Institute of Parasitic Diseases, Yunnan, China
| | - James Kelley
- World Health Organization, Regional Office for the Western Pacific, Manila, Philippines
| | | | - Maria Dorina Bustos
- World Health Organization, Regional Office for South-East Asia, New Delhi, India
| | | | - Luciano Tuseo
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia
- World Health Organization, Regional Office for the Western Pacific, Manila, Philippines
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Meier-Scherling CPG, Watson OJ, Asua V, Ghinai I, Katairo T, Garg S, Conrad M, Rosenthal PJ, Okell LC, Bailey JA. Selection of artemisinin partial resistance Kelch13 mutations in Uganda in 2016-22 was at a rate comparable to that seen previously in South-East Asia. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.02.03.24302209. [PMID: 38352505 PMCID: PMC10862983 DOI: 10.1101/2024.02.03.24302209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Background Artemisinin partial resistance, mediated by mutations in the Plasmodium falciparum Kelch13 protein (K13), rapidly spread in South-East Asia (SEA), undermining antimalarial efficacies of artemisinin-based combination therapies (ACT). Validated K13 mutations have recently arisen in Africa, but rates of increase are not well characterized. Methods We investigated K13 mutation prevalence at 16 sites in Uganda (2016-2022, 6586 samples), and five sites in SEA (2003-2018, 5465 samples) by calculating selection coefficients using Bayesian mixed-effect linear models. We then tested whether SEA K13 mutation prevalence could have been forecast accurately using up to the first five years of available data and forecast future K13 mutation prevalence in Uganda. Findings The selection coefficient for the prevalence of relevant K13 mutations (441L, 469F/Y, 561H, 675V) was estimated at s=0·383 (95% CrI: 0·247 - 0·528) per year, a 38% relative prevalence increase. Selection coefficients across Uganda were s=0·968 (0·463 - 1·569) for 441L, s=0·153 (-0·445 - 0·727) for 469F, s=0·222 (-0·011 - 0·398) for 469Y, and s=0·152 (-0·023 - 0·312) for 675V. In SEA, the selection coefficient was s=-0·005 (-0·852 - 0·814) for 539T, s=0·574 (-0·092 - 1·201) for 580Y, and s=0·308 (0·089 - 0·536) for all validated K13 mutations. Forecast prevalences for Uganda assuming constant selection neared fixation (>95% prevalence) within a decade (2028-2033) for combined K13 mutations. Interpretation The selection of K13 mutations in Uganda was at a comparable rate to that observed in SEA, suggesting K13 mutations may continue to increase quickly in Uganda. Funding NIH R01AI156267, R01AI075045, and R01AI089674.
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Affiliation(s)
| | - Oliver J Watson
- Medical Research Council Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Victor Asua
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Thomas Katairo
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Shreeya Garg
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Melissa Conrad
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Philip J. Rosenthal
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Lucy C Okell
- Medical Research Council Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Jeffrey A. Bailey
- Center for Computational Molecular Biology, Brown University, Providence, RI, USA
- Department of Pathology and Laboratory Medicine, Warren Alpert Medical School, Brown University, RI, USA
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3
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Platon L, Ménard D. Plasmodium falciparum ring-stage plasticity and drug resistance. Trends Parasitol 2024; 40:118-130. [PMID: 38104024 DOI: 10.1016/j.pt.2023.11.007] [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: 09/26/2023] [Revised: 11/15/2023] [Accepted: 11/15/2023] [Indexed: 12/19/2023]
Abstract
Malaria is a life-threatening tropical disease caused by parasites of the genus Plasmodium, of which Plasmodium falciparum is the most lethal. Malaria parasites have a complex life cycle, with stages occurring in both the Anopheles mosquito vector and human host. Ring stages are the youngest form of the parasite in the intraerythrocytic developmental cycle and are associated with evasion of spleen clearance, temporary growth arrest (TGA), and drug resistance. This formidable ability to survive and develop into mature, sexual, or growth-arrested forms demonstrates the inherent population heterogeneity. Here we highlight the role of the ring stage as a crossroads in parasite development and as a reservoir of surviving cells in the human host via TGA survival mechanisms.
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Affiliation(s)
- Lucien Platon
- Institut Pasteur, Université Paris Cité, Malaria Genetics and Resistance Unit, INSERM U1201, F-75015 Paris, France; Sorbonne Université, Collège Doctoral ED 515 Complexité du Vivant, F-75015 Paris, France; Université de Strasbourg, Institute of Parasitology and Tropical Diseases, UR7292 Dynamics of Host-Pathogen Interactions, F-67000 Strasbourg, France.
| | - Didier Ménard
- Institut Pasteur, Université Paris Cité, Malaria Genetics and Resistance Unit, INSERM U1201, F-75015 Paris, France; Institut Pasteur, Université Paris Cité, Malaria Parasite Biology and Vaccines Unit, F-75015 Paris, France; Université de Strasbourg, Institute of Parasitology and Tropical Diseases, UR7292 Dynamics of Host-Pathogen Interactions, F-67000 Strasbourg, France; CHU Strasbourg, Laboratory of Parasitology and Medical Mycology, F-67000 Strasbourg, France.
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Suphakhonchuwong N, Rungsihirunrat K, Kuesap J. Surveillance of drug resistance molecular markers in Plasmodium vivax before and after introduction of dihydroartemisinin and piperaquine in Thailand: 2009-2019. Parasitol Res 2023; 122:2871-2883. [PMID: 37725258 DOI: 10.1007/s00436-023-07977-2] [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: 05/30/2023] [Accepted: 09/12/2023] [Indexed: 09/21/2023]
Abstract
Resistance to antimalarial drugs is a serious issue around the world. Widespread Plasmodium vivax and P. falciparum coinfections are commonly found in Thailand. Dihydroartemisinin and piperaquine (DHA-PPQ) have been used as first-line treatments for P. falciparum since 2015, and chloroquine (CQ) and primaquine (PQ) have remained first-line drugs for P. vivax for more than 60 years. Coinfections may lead parasites to evolve with regard to genetics under selective drug pressure. This study is aimed at investigating genes linked to antimalarial resistance in P. vivax before and after introduction of DHA-PPQ as a new drug regimen in Thailand. A total of 400 P. vivax isolates were collected from samples along the Thai-Myanmar and Thai-Malaysian borders before (2009-2015) and after (2016-2019) introduction of DHA-PPQ. Genomic DNA of P. vivax was obtained and subjected to analysis of five drug resistance-associated genes (Pvdhfr, Pvdhps, Pvmdr1, Pvcrt-o, and PvK12) by nested polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and nucleotide sequencing. A high prevalence of Pvdhfr was found in both endemic areas over the period. The quadruple (57I/58R/61M/117T) Pvdhfr haplotype was predominant in both periods in both endemic areas. Although the wild-type haplotype of Pvdhps was predominant in Thai-Malaysian isolates in both periods, a single mutant haplotype (383G) was dominant in Thai-Myanmar isolates during both periods. A low prevalence of the Pvmdr1 976F mutation was found in both periods among Thai-Myanmar isolates. A significant decrease in Pvmdr1 976F was identified in Thai-Malaysian isolates from the second period (p < 0.01). Only one nonsynonymous mutation of Pvcrt-o (193E) and one synonymous mutation of PvK12 (R584) were detected in four isolates (4.7%) and one isolate (0.5%) in the first period among Thai-Myanmar isolates, respectively. Thus, with limited clinical efficacy data, the low prevalence of drug-resistance markers may suggest that there is a low prevalence of P. vivax-resistant strains and that the current drug regimen for P. vivax is still effective for treating this P. vivax parasite population. Continued surveillance of antimalarial drug resistance markers and monitoring of clinical drug efficacy should be conducted for epidemiological and policy implications.
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Affiliation(s)
| | | | - Jiraporn Kuesap
- Faculty of Allied Health Sciences, Thammasat University, Pathumthani, 12120, Thailand.
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Li M, Liu H, Tang L, Yang H, Bustos MDG, Tu H, Ringwald P. Genetic characteristics of P. falciparum parasites collected from 2012 to 2016 and anti-malaria resistance along the China-Myanmar border. PLoS One 2023; 18:e0293590. [PMID: 37948402 PMCID: PMC10637670 DOI: 10.1371/journal.pone.0293590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 10/16/2023] [Indexed: 11/11/2023] Open
Abstract
BACKGROUNDS The therapeutic efficacy studies of DHA-PIP for uncomplicated Plasmodium falciparum patients were implemented from 2012 to 2016 along China (Yunnan province)-Myanmar border, which verified the high efficacy of DHA-PIP. With the samples collected in these studies, the genetic characteristics of P. falciparum parasites based on in vivo parasite clearance time (PCT) was investigated to explore if these parasites had developed resistance to DHA and PIP at molecular level. METHODS The genetic characteristics were investigated based on K13 genotypes, copy numbers of genes pfpm2 and pfmdr1, and nine microsatellite loci (Short Tandem Repeats, STR) flanking the K13 gene on chromosome 13. The PCT 50s were compared based on different K13 genotypes, sites, periods and copy numbers. RESULTS In the NW (North-West Yunnan province bordering with Myanmar) region, F446I was the main K13 genotype. No significant differences for PCT 50s presented among three K13 genotypes. In SW (South-West Yunnan province bordering with Myanmar) region, only wild K13 genotype was detected in all parasite isolates whose PCT 50s was significantly longer than those in NW region. For the copy numbers of genes, parasite isolates containing multiple copies of pfmdr1 gene were found in both regions, but only single copy of pfpm2 gene was detected. Though the prevalence of parasite isolates with multiple copies of pfmdr1 gene in SW region was higher than that in NW region, no difference in PCT 50s were presented between isolates with single and multiple copies of pfmdr1 gene. The median He values of F446I group and Others (Non-F446I K13 mutation) group were 0.08 and 0.41 respectively. The mean He values of ML group (Menglian County in SW) and W (wild K13 genotype in NW) group were 0 and 0.69 respectively. The mean Fst values between ML and W groups were significantly higher than the other two K13 groups. CONCLUSIONS P. falciparum isolates in NW and SW regions had very different genetic characteristics. The F446I was hypothesized to have independently appeared and spread in NW region from 2012 and 2016. The high susceptibility of PIP had ensured the efficacy of DHA-PIP in vivo. Multiple copy numbers of pfmdr1 gene might be a potential cause of prolonged clearance time of ACTs drugs along China-Myanmar border. TRIAL REGISTRATION Trial registration: ISRCTN, ISRCTN 11775446. Registered 17 April 2020-Retrospectively registered, the registered name was Investigating resistance to DHA-PIP for the treatment of Plasmodium falciparum malaria and chloroquine for the treatment of Plasmodium vivax malaria in Yunnan, China. http://www.isrctn.com/ISRCTN11775446.
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Affiliation(s)
- Mei Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Beijing, China
- NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, Shanghai, China
- National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Hui Liu
- Yunnan Institute of Parasitic Diseases, Yunnan, 665000, China
| | - Linhua Tang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Beijing, China
- NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, Shanghai, China
- National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Henglin Yang
- Yunnan Institute of Parasitic Diseases, Yunnan, 665000, China
| | | | - Hong Tu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Beijing, China
- NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, Shanghai, China
- National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Pascal Ringwald
- Coordinator Director Office, Global Malaria Programme, Geneva, Swizerland
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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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Win KN, Manopwisedjaroen K, Phumchuea K, Suansomjit C, Chotivanich K, Lawpoolsri S, Cui L, Sattabongkot J, Nguitragool W. Molecular markers of dihydroartemisinin-piperaquine resistance in northwestern Thailand. Malar J 2022; 21:352. [PMID: 36437462 PMCID: PMC9701414 DOI: 10.1186/s12936-022-04382-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 11/11/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Dihydroartemisinin-piperaquine (DHA-PPQ) combination therapy is the current first-line treatment for Plasmodium falciparum malaria in Thailand. Since its introduction in 2015, resistance to this drug combination has emerged in the eastern part of the Greater Mekong Subregion including the eastern part of Thailand near Cambodia. This study aimed to assess whether the resistance genotypes have arisen the western part of country. METHODS Fifty-seven P. falciparum-infected blood samples were collected in Tak province of northwestern Thailand between 2013 and 2019. Resistance to DHA was examined through the single nucleotide polymorphisms (SNPs) of kelch13. PPQ resistance was examined through the copy number plasmepsin-2 and the SNPs of Pfcrt. RESULTS Among the samples whose kelch13 were successfully sequenced, approximately half (31/55; 56%) had mutation associated with artemisinin resistance, including G533S (23/55; 42%), C580Y (6/55; 11%), and G538V (2/55; 4%). During the study period, G533S mutation appeared and increased from 20% (4/20) in 2014 to 100% (9/9) in 2019. No plasmepsin-2 gene amplification was observed, but one sample (1/54) had the Pfcrt F145I mutation previously implicated in PPQ resistance. CONCLUSIONS Kelch13 mutation was common in Tak Province in 2013-2019. A new mutation G533S emerged in 2014 and rose to dominance in 2019. PPQ resistance marker Pfcrt F145I was also detected in 2019. Continued surveillance of treatment efficacy and drug resistance markers is warranted.
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Affiliation(s)
- Khine Nwe Win
- grid.10223.320000 0004 1937 0490Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Khajohnpong Manopwisedjaroen
- grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Kanit Phumchuea
- grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Chayanut Suansomjit
- grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Kesinee Chotivanich
- grid.10223.320000 0004 1937 0490Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Saranath Lawpoolsri
- grid.10223.320000 0004 1937 0490Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Liwang Cui
- grid.170693.a0000 0001 2353 285XDepartment of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612 USA
| | - Jetsumon Sattabongkot
- grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand
| | - Wang Nguitragool
- grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand ,grid.10223.320000 0004 1937 0490Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Rd, Ratchathewi, Bangkok, 10400 Thailand
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Guillot C, Bouchard C, Aenishaenslin C, Berthiaume P, Milord F, Leighton PA. Criteria for selecting sentinel unit locations in a surveillance system for vector-borne disease: A decision tool. Front Public Health 2022; 10:1003949. [PMID: 36438246 PMCID: PMC9686450 DOI: 10.3389/fpubh.2022.1003949] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 10/10/2022] [Indexed: 11/11/2022] Open
Abstract
Objectives With vector-borne diseases emerging across the globe, precipitated by climate change and other anthropogenic changes, it is critical for public health authorities to have well-designed surveillance strategies in place. Sentinel surveillance has been proposed as a cost-effective approach to surveillance in this context. However, spatial design of sentinel surveillance system has important impacts on surveillance outcomes, and careful selection of sentinel unit locations is therefore an essential component of planning. Methods A review of the available literature, based on the realist approach, was used to identify key decision issues for sentinel surveillance planning. Outcomes of the review were used to develop a decision tool, which was subsequently validated by experts in the field. Results The resulting decision tool provides a list of criteria which can be used to select sentinel unit locations. We illustrate its application using the case example of designing a national sentinel surveillance system for Lyme disease in Canada. Conclusions The decision tool provides researchers and public health authorities with a systematic, evidence-based approach for planning the spatial design of sentinel surveillance systems, taking into account the aims of the surveillance system and disease and/or context-specific considerations.
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Affiliation(s)
- Camille Guillot
- Groupe de recherche en épidémiologie des zoonoses et santé publique (GREZOSP), Faculté de médecine vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada,Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada,Centre de recherche en santé publique de l'Université de Montréal et du CIUSSS du Centre-Sud-de-l'île-de-Montréal (CReSP), Montréal, QC, Canada,*Correspondence: Camille Guillot
| | - Catherine Bouchard
- Groupe de recherche en épidémiologie des zoonoses et santé publique (GREZOSP), Faculté de médecine vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada,Public Health Risk Sciences Division, National Microbiology Laboratory, Public Health Agency of Canada, St. Hyacinthe, QC, Canada
| | - Cécile Aenishaenslin
- Groupe de recherche en épidémiologie des zoonoses et santé publique (GREZOSP), Faculté de médecine vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada
| | - Philippe Berthiaume
- Groupe de recherche en épidémiologie des zoonoses et santé publique (GREZOSP), Faculté de médecine vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada,Public Health Risk Sciences Division, National Microbiology Laboratory, Public Health Agency of Canada, St. Hyacinthe, QC, Canada
| | - François Milord
- Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Patrick A. Leighton
- Groupe de recherche en épidémiologie des zoonoses et santé publique (GREZOSP), Faculté de médecine vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada,Centre de recherche en santé publique de l'Université de Montréal et du CIUSSS du Centre-Sud-de-l'île-de-Montréal (CReSP), Montréal, QC, Canada
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9
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Lek D, Rachmat A, Harrison D, Chin G, Chaoratanakawee S, Saunders D, Menard D, Rogers WO. Efficacy of three anti-malarial regimens for uncomplicated Plasmodium falciparum malaria in Cambodia, 2009-2011: a randomized controlled trial and brief review. Malar J 2022; 21:259. [PMID: 36071520 PMCID: PMC9450427 DOI: 10.1186/s12936-022-04279-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 08/28/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Anti-malarial resistance remains an important public health challenge in Cambodia. The effectiveness of three therapies for uncomplicated falciparum malaria was evaluated in Oddar Meanchey province in Northern Cambodia from 2009 to 2011. METHODS In this randomized, open-label, parallel group-controlled trial, 211 subjects at least 5 years old with uncomplicated falciparum malaria were treated with 3 days of directly observed therapy: 63 received artesunate-mefloquine (AS/MQ), 77 received dihydroartemisinin-piperaquine (DHA/PPQ), and 71 received atovaquone-proguanil (ATQ/PG). The subjects were followed for 42 days or until recurrent parasitaemia. Genotyping of msp1, msp2, and glurp among individual parasite isolates distinguished recrudescence from reinfection. Pfmdr1 copy number was measured by real-time PCR and half-maximal parasite inhibitory concentrations (IC50) were measured in vitro by 48-h isotopic hypoxanthine incorporation assay. RESULTS The per-protocol PCR-adjusted efficacy (95% confidence interval) at 42 days was 80.6% (70.8-90.5%) for AS/MQ, 97.2% (93.3-100%) for DHA/PPQ, and 92.9% (86.1-99.6%) for ATQ/PG. On day 3, 57.9% remained parasitaemic in the AS/MQ and DHA/PPQ arms. At baseline, 46.9% had microscopic Plasmodium falciparum gametocytaemia. Both recurrences in the DHA/PPQ arm lost Pfmdr1 copy number amplification at recrudescence. All four recurrences in the ATQ/PG arm were wild-type for cytochrome bc1. One subject withdrew from the ATQ/PG arm due to drug allergy. CONCLUSIONS This study was conducted at the epicentre of substantial multi-drug resistance that emerged soon thereafter. Occurring early in the national transition from AS/MQ to DHA/PPQ, both DHA/PPQ and ATQ/PG had acceptable efficacy against uncomplicated falciparum malaria. However, efficacy of AS/MQ was only 80% with apparent mefloquine resistance based on elevated Pfmdr1 copy number and IC50. By 2009, there was already significant evidence of artemisinin resistance not previously reported at the Northern Cambodia-Thai border. This study suggests the basis for early development of significant DHA/PPQ failures within 3 years of introduction. Artemisinin resistance likely occurred on the Northern border concurrently with that reported along the Western border in Pailin. Trial registration This legacy trial was conducted prior to International Committee of Medical Journal Editors' requirements for preregistration on ClinicalTrials.gov. The full protocol has been provided.
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Affiliation(s)
- Dysoley Lek
- National Centre for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia.
| | - Agus Rachmat
- U.S. Naval Medical Research Unit 2, Phnom Penh, Cambodia
| | | | - Geoffrey Chin
- Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | | | - David Saunders
- Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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10
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Kubota R, Ishino T, Iwanaga S, Shinzawa N. Evaluation of the Effect of Gene Duplication by Genome Editing on Drug Resistance in Plasmodium falciparum. Front Cell Infect Microbiol 2022; 12:915656. [PMID: 35865822 PMCID: PMC9294729 DOI: 10.3389/fcimb.2022.915656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/01/2022] [Indexed: 11/22/2022] Open
Abstract
The emergence and spread of drug-resistant Plasmodium falciparum have compromised antimalarial efficacy and threatened the global malaria elimination campaign using artemisinin combination therapies. The impacts of amino acid substitutions in antimalarial drug resistance-associated genes on drug susceptibility have been investigated; however, the effects of amplification of those genes remain unexplored due to the lack of robust genetic approaches. Here, we generated transgenic P. falciparum parasites with an additional copy of a drug resistance-associated gene using the highly efficient CRISPR/Cas9 system and investigated their drug response. Insertion of a drug resistance-associated gene expression cassette in the genome resulted in a roughly twofold increase of mRNA levels of the target gene mdr1, which encodes multidrug resistance protein 1. The gene duplication event contributed to resistance to mefloquine, lumefantrine, and dihydroartemisinin, while the duplication of a genomic region encoding plasmepsin 2 and plasmepsin 3 did not affect resistance to antimalarial drugs, including piperaquine. We further demonstrated that mdr1 mRNA expression levels are strongly associated with mefloquine resistance in several field-derived P. falciparum lines with various genetic backgrounds. This study provides compelling evidence that mdr1 could serve as a molecular marker for the surveillance of mefloquine-resistant parasites. Long DNA integration into parasite genomes using the CRISPR/Cas9 system provides a useful tool for the evaluation of the effect of copy number variation on drug response.
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Affiliation(s)
- Rie Kubota
- Department of Parasitology and Tropical Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tomoko Ishino
- Department of Parasitology and Tropical Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shiroh Iwanaga
- Department of Molecular Protozoology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Naoaki Shinzawa
- Department of Parasitology and Tropical Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- *Correspondence: Naoaki Shinzawa,
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11
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Assessing the Roles of Molecular Markers of Antimalarial Drug Resistance and the Host Pharmacogenetics in Drug-Resistant Malaria. J Trop Med 2022; 2022:3492696. [PMID: 35620049 PMCID: PMC9129956 DOI: 10.1155/2022/3492696] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/17/2022] [Accepted: 04/29/2022] [Indexed: 01/11/2023] Open
Abstract
Malaria caused by the Plasmodium parasites is a major public health concern in malaria-endemic regions with P. falciparum causing the most severe form of the disease. The use of antimalarial drugs for the management of the disease proves to be one of the best methods to manage the disease. Unfortunately, P. falciparum has developed resistance to almost all the current in-use antimalarial drugs. Parasite development of resistance is primarily caused by both parasite and host genetic factors. The parasite genetic factors involve undergoing mutation in the drug target sites or increasing the drug target gene copy number to prevent the intended action of the antimalarial drugs. The host pharmacogenetic factors which determine how a particular antimalarial drug is metabolized could result in variations of drug plasma concentration and consequently contribute to variable treatment outcomes and the emergence or propagation of resistant parasites. Since both host and parasite genomes play a role in antimalarial drug action, a key question often asked is, “which of the two strongly drives or controls antimalarial drug resistance?” A major finding in our recent study published in the Malaria Journal indicates that the parasite's genetic factors rather than the host are likely to energize resistance to an antimalarial drug. However, others have reported contrary findings suggesting that the host genetic factors are the force behind resistance to antimalarial drugs. To bring clarity to these observations, there is the need for deciphering the major driving force behind antimalarial drug resistance through optimized strategies aimed at alleviating the phenomenon. In this direction, literature was systematically reviewed to establish the role and importance of each of the two factors aforementioned in the etiology of drug-resistant malaria. Using Internet search engines such as Pubmed and Google, we looked for terms likely to give the desired information which we herein present. We then went ahead to leverage the obtained information to discuss the globally avid aim of combating antimalarial drug resistance.
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12
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Population Pharmacokinetics of Antimalarial Naphthoquine in Combination with Artemisinin in Tanzanian Children and Adults: Dose Optimization. Antimicrob Agents Chemother 2022; 66:e0169621. [PMID: 35465706 PMCID: PMC9112936 DOI: 10.1128/aac.01696-21] [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] [Indexed: 11/20/2022] Open
Abstract
The combination antimalarial therapy of artemisinin-naphthoquine (ART-NQ) was developed as a single-dose therapy, aiming to improve adherence relative to the multiday schedules of other artemisinin combination therapies. The pharmacokinetics of ART-NQ has not been well characterized, especially in children. A pharmacokinetic study was conducted in adults and children over 5 years of age (6 to 10, 11 to 17, and ≥18 years of age) with uncomplicated malaria in Tanzania. The median weights for the three age groups were 20, 37.5, and 55 kg, respectively. Twenty-nine patients received single doses of 20 mg/kg of body weight for artemisinin and 8 mg/kg for naphthoquine, and plasma drug concentrations were assessed at 13 time points over 42 days from treatment. We used nonlinear mixed-effects modeling to interpret the data, and allometric scaling was employed to adjust for the effect of body size. The pharmacokinetics of artemisinin was best described by one-compartment model and that of naphthoquine by a two-compartment disposition model. Clearance values for a typical patient (55-kg body weight and 44.3-kg fat-free mass) were estimated as 66.7 L/h (95% confidence interval [CI], 57.3 to 78.5 L/h) for artemisinin and 44.2 L/h (95% CI, 37.9 to 50.6 L/h) for naphthoquine. Nevertheless, we show via simulation that patients weighing ≥70 kg achieve on average a 30% lower day 7 concentration compared to a 48-kg reference patient at the doses tested, suggesting dose increases may be warranted to ensure adequate exposure. (This study has been registered at ClinicalTrials.gov under identifier NCT01930331.).
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13
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Asih PBS, Rozi IE, Dewayanti FK, Wangsamuda S, Zulfah S, Robaha M, Hutahaean J, Anggraeni ND, Kusumaningsih M, Mulyani PS, Sariwati E, Basri HH, Bustos MDG, Syafruddin D. Efficacy and safety of dihydroartemisinin–piperaquine for the treatment of uncomplicated Plasmodium falciparum and Plasmodium vivax malaria in Papua and Sumatra, Indonesia. Malar J 2022; 21:95. [PMID: 35305658 PMCID: PMC8934463 DOI: 10.1186/s12936-022-04101-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 02/23/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Dihydroartemisinin–piperaquine (DHA–PPQ) has been adopted as first-line therapy for uncomplicated falciparum malaria in Indonesia since 2010. The efficacy of DHA–PPQ was evaluated in 2 sentinel sites in Keerom District, Papua and Merangin District, Jambi, Sumatra from April 2017 to April 2018.
Methods
Clinical and parasitological parameters were monitored over a 42-day period following the World Health Organization standard in vivo protocol and subjects meeting the inclusion criteria were treated with DHA–PPQ once daily for 3 days, administered orally.
Results
In Papua, 6339 subjects were screened through active and passive cases detection. Of the 114 falciparum and 81 vivax cases enrolled, 102 falciparum and 80 vivax cases completed the 42 day follow up, and 12 falciparum and 1 vivax cases were either lost to follow up or withdrawn. Kaplan–Meier analysis of microscopy readings of 102 falciparum cases revealed 93.1% (95% CI 86.4–97.2) as Adequate Clinical and Parasitological Response (ACPR). No delay in parasite clearance nor severe adverse reaction was observed. Recurrent parasites of Plasmodium falciparum were detected in 7 cases and categorized as late treatment failures (LTF) at days 21, 35, and 42 and one of which was reinfected by Plasmodium vivax at day 42. Two cases were confirmed as recrudescent infection and 4 were re-infection. The PCR-corrected DHA–PPQ efficacy for P. falciparum was 97.9% (95% CI 92.7–99.7). Of the 80 cases of P. vivax that were followed up, 71 cases were completely cured and classified as ACPR (88.8%, 95% CI 79.7–94.7) and 9 cases showed recurrent infection at days 35 and 42, and classified as LTF. In Sumatra, of the 751 subjects screened, 35 vivax subjects enrolled, 34 completed the 42 day follow up. Thirty-three cases were completely cured and classified as ACPR (97.1%, 95% CI 84.7–99.9) and 1 recurrent infection was observed and classified as LTF. No delay in parasite clearance nor severe adverse reaction was observed. Analysis of the Pfk13 gene in P. falciparum cases from Papua revealed no mutations associated with artemisinin resistance in the 20 SNPs previously reported. Analysis of the Pfpm2 gene at day 0 and day of recurrence in recrudescent cases revealed the same single copy number, whereas 3 of the 4 re-infection cases carried 2–3 Pfpm2 gene copy numbers.
Conclusion
Treatment of falciparum and vivax malaria cases with DHA–PPQ showed a high efficacy and safety.
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14
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Ocan M, Ashaba FK, Mwesigwa S, Edgar K, Kamya MR, Nsobya SL. Prevalence of arps10, fd, pfmdr-2, pfcrt and pfkelch13 gene mutations in Plasmodium falciparum parasite population in Uganda. PLoS One 2022; 17:e0268095. [PMID: 35511795 PMCID: PMC9070901 DOI: 10.1371/journal.pone.0268095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 04/21/2022] [Indexed: 11/18/2022] Open
Abstract
In Uganda, Artemether-Lumefantrine and Artesunate are recommended for uncomplicated and severe malaria respectively, but are currently threatened by parasite resistance. Genetic and epigenetic factors play a role in predisposing Plasmodium falciparum parasites to acquiring Pfkelch13 (K13) mutations associated with delayed artemisinin parasite clearance as reported in Southeast Asia. In this study, we report on the prevalence of mutations in the K13, pfmdr-2 (P. falciparum multidrug resistance protein 2), fd (ferredoxin), pfcrt (P. falciparum chloroquine resistance transporter), and arps10 (apicoplast ribosomal protein S10) genes in Plasmodium falciparum parasites prior to (2005) and after (2013) introduction of artemisinin combination therapies for malaria treatment in Uganda. A total of 200 P. falciparum parasite DNA samples were screened. Parasite DNA was extracted using QIAamp DNA mini kit (Qiagen, GmbH, Germany) procedure. The PCR products were sequenced using Sanger dideoxy sequencing method. Of the 200 P. falciparum DNA samples screened, sequencing for mutations in K13, pfmdr-2, fd, pfcrt, arps10 genes was successful in 142, 186, 141, 128 and 74 samples respectively. Overall, we detected six (4.2%, 6/142; 95%CI: 1.4-7.0) K13 single nucleotide polymorphisms (SNPs), of which 3.9% (2/51), 4.4% (4/91) occurred in 2005 and 2013 samples respectively. All four K13 SNPs in 2013 samples were non-synonymous (A578S, E596V, S600C and E643K) while of the two SNPs in 2005 samples, one (Y588N) is non-synonymous and the other (I587I) is synonymous. There was no statistically significant difference in the prevalence of K13 (p = 0.112) SNPs in the samples collected in 2005 and 2013. The overall prevalence of SNPs in pfmdr-2 gene was 39.8% (74/186, 95%CI: 25.1-50.4). Of this, 4.2% (4/95), 76.9% (70/91) occurred in 2005 and 2013 samples respectively. In 2005 samples only one SNP, Y423F (4.2%, 4/95) was found while in 2013, Y423F (38.5%, 35/91) and I492V (38.5%, 35/91) SNPs in the pfmdr-2 gene were found. There was a statistically significant difference in the prevalence of pfmdr-2 SNPs in the samples collected in 2005 and 2013 (p<0.001). The overall prevalence of arps10 mutations was 2.7% (2/72, 95%CI: 0.3-4.2). Two mutations, V127M (4.5%: 1/22) and D128H (4.5%: 1/22) in the arps10 gene were each found in P. falciparum parasite samples collected in 2013. There was no statistically significant difference in the prevalence of arps10 SNPs in the samples collected in 2005 and 2013 (p = 0.238). There were more pfmdr-2 SNPs in P. falciparum parasites collected after introduction of Artemisinin combination therapies in malaria treatment. This is an indicator of the need for continuous surveillance to monitor emergence of molecular markers of artemisinin resistance and its potential drivers in malaria affected regions globally.
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Affiliation(s)
- Moses Ocan
- Department of Pharmacology & Therapeutics, Makerere University, Kampala, Uganda
- * E-mail:
| | | | - Savannah Mwesigwa
- Department of Immunology and Molecular Biology, Makerere University, Kampala, Uganda
| | - Kigozi Edgar
- Makerere University Biomedical Research Center, Kampala, Uganda
| | - Moses R. Kamya
- Infectious Disease Research Collaboration (IDRC), Kampala, Uganda
- Department of Medicine, Makerere University, Kampala, Uganda
| | - Sam L. Nsobya
- Infectious Disease Research Collaboration (IDRC), Kampala, Uganda
- Department of Pathology, Kampala, Uganda
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15
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Reactive Oxygen Species as the Brainbox in Malaria Treatment. Antioxidants (Basel) 2021; 10:antiox10121872. [PMID: 34942976 PMCID: PMC8698694 DOI: 10.3390/antiox10121872] [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: 10/15/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 02/08/2023] Open
Abstract
Several measures are in place to combat the worldwide spread of malaria, especially in regions of high endemicity. In part, most common antimalarials, such as quinolines and artemisinin and its derivatives, deploy an ROS-mediated approach to kill malaria parasites. Although some antimalarials may share similar targets and mechanisms of action, varying levels of reactive oxygen species (ROS) generation may account for their varying pharmacological activities. Regardless of the numerous approaches employed currently and in development to treat malaria, concerningly, there has been increasing development of resistance by Plasmodium falciparum, which can be connected to the ability of the parasites to manage the oxidative stress from ROS produced under steady or treatment states. ROS generation has remained the mainstay in enforcing the antiparasitic activity of most conventional antimalarials. However, a combination of conventional drugs with ROS-generating ability and newer drugs that exploit vital metabolic pathways, such antioxidant machinery, could be the way forward in effective malaria control.
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16
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Coonahan ES, Yang KA, Pecic S, De Vos M, Wellems TE, Fay MP, Andersen JF, Tarning J, Long CA. Structure-switching aptamer sensors for the specific detection of piperaquine and mefloquine. Sci Transl Med 2021; 13:13/585/eabe1535. [PMID: 33731432 DOI: 10.1126/scitranslmed.abe1535] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 02/22/2021] [Indexed: 12/28/2022]
Abstract
Tracking antimalarial drug use and efficacy is essential for monitoring the current spread of antimalarial drug resistance. However, available methods for determining tablet quality and patient drug use are often inaccessible, requiring well-equipped laboratories capable of performing liquid chromatography-mass spectrometry (LC-MS). Here, we report the development of aptamer-based fluorescent sensors for the rapid, specific detection of the antimalarial compounds piperaquine and mefloquine-two slow-clearing partner drugs in current first-line artemisinin-based combination therapies (ACTs). Highly selective DNA aptamers were identified that bind piperaquine and mefloquine with dissociation constants (K d's) measured in the low nanomolar range via two independent methods. The aptamers were isolated from a library of single-stranded DNA molecules using a capture-systematic evolution of ligands by exponential enrichment (SELEX) technique and then adapted into structure-switching aptamer fluorescent sensors. Sensor performance was optimized for the detection of drug from human serum and crushed tablets, resulting in two sensing platforms. The patient sample platform was validated against an LC-MS standard drug detection method in samples from healthy volunteers and patients with malaria. This assay provides a rapid and inexpensive method for tracking antimalarial drug use and quality for the containment and study of parasite resistance, a major priority for malaria elimination campaigns. This sensor platform allows for flexibility of sample matrix and can be easily adapted to detect other small-molecule drugs.
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Affiliation(s)
- Erin S Coonahan
- Laboratory of Malaria and Vector Research, NIAID, NIH, MD 20892-8132, USA.,Institute of Biomedical Engineering, University of Oxford, Oxford OX3 7DQ, UK.,Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Kyung-Ae Yang
- Department of Medicine, Columbia University, New York, NY 10032, USA
| | - Stevan Pecic
- Department of Chemistry and Biochemistry, California State University , Fullerton, CA 92831, USA
| | - Maarten De Vos
- Institute of Biomedical Engineering, University of Oxford, Oxford OX3 7DQ, UK.,Department of Electrical Engineering (ESAT), KU Leuven, Leuven 3000, Belgium.,Department of Development and Regeneration, KU Leuven, Leuven 3000, Belgium
| | - Thomas E Wellems
- Laboratory of Malaria and Vector Research, NIAID, NIH, MD 20892-8132, USA
| | - Michael P Fay
- Biostatistics Research Branch, DCR, NIAID, NIH, Rockville, MD 20852, USA
| | - John F Andersen
- Laboratory of Malaria and Vector Research, NIAID, NIH, MD 20892-8132, USA
| | - Joel Tarning
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7LG, UK
| | - Carole A Long
- Laboratory of Malaria and Vector Research, NIAID, NIH, MD 20892-8132, USA.
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17
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Roesch C, Mairet-Khedim M, Kim S, Lek D, Popovici J, Witkowski B. Impact of the first-line treatment shift from dihydroartemisinin/piperaquine to artesunate/mefloquine on Plasmodium vivax drug susceptibility in Cambodia. J Antimicrob Chemother 2021; 75:1766-1771. [PMID: 32211790 PMCID: PMC7303819 DOI: 10.1093/jac/dkaa092] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/16/2020] [Accepted: 02/20/2020] [Indexed: 02/06/2023] Open
Abstract
Background Cambodia is the epicentre of the emergence of Plasmodium falciparum drug resistance. Much less is known regarding the drug susceptibility of the co-endemic Plasmodium vivax. Only in vitro drug assays can determine the parasite’s intrinsic susceptibility, but these are challenging to implement for P. vivax and rarely performed. Objectives To evaluate the evolution of Cambodian P. vivax susceptibility to antimalarial drugs and determine their association with putative markers of drug resistance. Methods In vitro response to three drugs used in the past decade in Cambodia was measured for 52 clinical isolates from Eastern Cambodia collected between 2015 and 2018 and the sequence and copy number variation of their pvmdr1 and pvcrt genes were analysed. pvmdr1 polymorphism was also determined for an additional 250 isolates collected in Eastern Cambodia between 2014 and 2019. Results Among the 52 cryopreserved isolates tested, all were susceptible to the three drugs, with overall median IC50s of 16.1 nM (IQR 11.4–22.3) chloroquine, 3.4 nM (IQR 2.1–5.0) mefloquine and 4.6 nM (IQR 2.7–7.0) piperaquine. A significant increase in chloroquine and piperaquine susceptibility was observed between 2015 and 2018, unrelated to polymorphisms in pvcrt and pvmdr1. Susceptibility to mefloquine was significantly lower in parasites with a single mutation in pvmdr1 compared with isolates with multiple mutations. The proportion of parasites with this single mutation genotype increased between 2014 and 2019. Conclusions P. vivax with decreased susceptibility to mefloquine is associated with the introduction of mefloquine-based treatment during 2017–18.
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Affiliation(s)
- Camille Roesch
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia.,Malaria Translational Research Unit, Institut Pasteur, Paris & Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Mélissa Mairet-Khedim
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia.,Malaria Translational Research Unit, Institut Pasteur, Paris & Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Saorin Kim
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia.,Malaria Translational Research Unit, Institut Pasteur, Paris & Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Dysoley Lek
- National Center for Malariology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Jean Popovici
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia.,Malaria Translational Research Unit, Institut Pasteur, Paris & Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Benoit Witkowski
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia.,Malaria Translational Research Unit, Institut Pasteur, Paris & Institut Pasteur du Cambodge, Phnom Penh, Cambodia
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18
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Ippolito MM, Moser KA, Kabuya JBB, Cunningham C, Juliano JJ. Antimalarial Drug Resistance and Implications for the WHO Global Technical Strategy. CURR EPIDEMIOL REP 2021; 8:46-62. [PMID: 33747712 PMCID: PMC7955901 DOI: 10.1007/s40471-021-00266-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2021] [Indexed: 12/28/2022]
Abstract
PURPOSE OF REVIEW Five years have passed since the World Health Organization released its Global Technical Strategy for Malaria (GTS). In that time, progress against malaria has plateaued. This review focuses on the implications of antimalarial drug resistance for the GTS and how interim progress in parasite genomics and antimalarial pharmacology offer a bulwark against it. RECENT FINDINGS For the first time, drug resistance-conferring genes have been identified and validated before their global expansion in malaria parasite populations. More efficient methods for their detection and elaboration have been developed, although low-density infections and polyclonality remain a nuisance to be solved. Clinical trials of alternative regimens for multidrug-resistant malaria have delivered promising results. New agents continue down the development pipeline, while a nascent infrastructure in sub-Saharan Africa for conducting phase I trials and trials of transmission-blocking agents has come to fruition after years of preparation. SUMMARY These and other developments can help inform the GTS as the world looks ahead to the next two decades of its implementation. To remain ahead of the threat that drug resistance poses, wider application of genomic-based surveillance and optimization of existing and forthcoming antimalarial drugs are essential.
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Affiliation(s)
- Matthew M. Ippolito
- Divisions of Clinical Pharmacology and Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA
- The Johns Hopkins Malaria Research Institute, Johns Hopkins University School of Public Health, Baltimore, MD USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Kara A. Moser
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC USA
| | | | - Clark Cunningham
- School of Medicine, University of North Carolina, Chapel Hill, NC USA
| | - Jonathan J. Juliano
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of North Carolina, CB#7030, 130 Mason Farm Rd, Chapel Hill, NC 27599 USA
- Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina, Chapel Hill, NC USA
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC USA
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19
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Wang S, Xu S, Geng J, Si Y, Zhao H, Li X, Yang Q, Zeng W, Xiang Z, Chen X, Zhang Y, Li C, Kyaw MP, Cui L, Yang Z. Molecular Surveillance and in vitro Drug Sensitivity Study of Plasmodium falciparum Isolates from the China-Myanmar Border. Am J Trop Med Hyg 2020; 103:1100-1106. [PMID: 32588794 DOI: 10.4269/ajtmh.20-0235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The emergence and spread of resistance in Plasmodium falciparum to the frontline treatment artemisinin-based combination therapies in Southeast Asia require close monitoring of the situation. Here, we collected 36 clinical samples of P. falciparum from the China-Myanmar border in 2014-2016, adapted these parasites to continuous culture, and performed in vitro drug assays on seven antimalarial drugs. Data for 23 parasites collected in 2010 and 2012 from the same area reported in an early study were used to assess longitudinal changes in drug sensitivity. Parasites remained highly resistant to chloroquine (CQ) and pyrimethamine, whereas they were generally sensitive to mefloquine (MFQ), lumefantrine (LMF), naphthoquine (NQ), and pyronaridine (PND). Parasites showed a similar temporal trend in sensitivity to CQ, NQ, and PND, with gradual reduction in the half-maximal inhibitory concentrations (IC50s) after 2012. The IC50s to the aminoalcohol drugs MFQ, LMF, and quinine (QN) all significantly declined in 2014, followed by various degrees of increase in 2016. Pyrimethamine displayed a continuous increase in IC50 over the years. The Dd2-like P. falciparum chloroquine-resistant transporter mutations were fixed or nearly fixed in the parasite population. The P. falciparum multidrug resistance 1 F1226Y mutation was detected in 80% parasites in 2016 and associated with reduced sensitivity to LMF and QN (P < 0.05). The N51I in P. falciparum dihydrofolate reductase and K540E/N and A581G in P. falciparum dihydropteroate synthase that are associated with antifolate resistance were either fixed or were approaching fixation in recent years. This study provides an updated picture and temporal trend of antimalarial drug resistance in the China-Myanmar border region, which will serve as a reference for antimalarial treatment.
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Affiliation(s)
- Siqi Wang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Shiling Xu
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Jinting Geng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yu Si
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Hui Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xinxin Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Qi Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Weilin Zeng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Zheng Xiang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xi Chen
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yanmei Zhang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Cuiying Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | | | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
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20
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Dafalla OM, Alzahrani M, Sahli A, Al Helal MA, Alhazmi MM, Noureldin EM, Mohamed WS, Hamid TB, Abdelhaleem AA, Hobani YA, Arif OA, Bokar IM, Hakami AM, Eisa ZM. Kelch 13-propeller polymorphisms in Plasmodium falciparum from Jazan region, southwest Saudi Arabia. Malar J 2020; 19:397. [PMID: 33168025 PMCID: PMC7653757 DOI: 10.1186/s12936-020-03467-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/27/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Artemisinin-based combination therapy (ACT) is recommended at the initial phase for treatment of Plasmodium falciparum, to reduce morbidity and mortality in all countries where malaria is endemic. Polymorphism in portions of P. falciparum gene encoding kelch (K13)-propeller domains is associated with delayed parasite clearance after ACT. Of about 124 different non-synonymous mutations, 46 have been identified in Southeast Asia (SEA), 62 in sub-Saharan Africa (SSA) and 16 in both the regions. This is the first study designed to analyse the prevalence of polymorphism in the P. falciparum k13-propeller domain in the Jazan region of southwest Saudi Arabia, where malaria is endemic. METHODS One-hundred and forty P. falciparum samples were collected from Jazan region of southwest Saudi Arabia at three different times: 20 samples in 2011, 40 samples in 2016 and 80 samples in 2020 after the implementation of ACT. Plasmodium falciparum kelch13 (k13) gene DNA was extracted, amplified, sequenced, and analysed using a basic local alignment search tool (BLAST). RESULTS This study obtained 51 non-synonymous (NS) mutations in three time groups, divided as follows: 6 single nucleotide polymorphisms (SNPs) '11.8%' in samples collected in 2011 only, 3 (5.9%) in 2011and 2016, 5 (9.8%) in 2011 and 2020, 5 (9.8%) in 2016 only, 8 (15.7%) in 2016 and 2020, 14 (27.5%) in 2020 and 10 (19.6%) in all the groups. The BLAST revealed that the 2011 isolates were genetically closer to African isolates (53.3%) than Asian ones (46.7%). Interestingly, this proportion changed completely in 2020, to become closer to Asian isolates (81.6%) than to African ones (18.4%). CONCLUSIONS Despite the diversity of the identified mutations in the k13-propeller gene, these data did not report widespread artemisinin-resistant polymorphisms in the Jazan region where these samples were collected. Such a process would be expected to increase frequencies of mutations associated with the resistance of ACT.
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Affiliation(s)
| | - Mohammed Alzahrani
- Zoonotic and Vector - Borne Diseases Ministry of Health, Riyadh, Saudi Arabia
| | - Ahmed Sahli
- Zoonotic and Vector - Borne Diseases Ministry of Health, Riyadh, Saudi Arabia
| | | | | | | | | | | | | | - Yahya Ali Hobani
- National Center for Diseases Prevention and Control, Jazan, Saudi Arabia
| | - Ommar Ali Arif
- National Center for Diseases Prevention and Control, Jazan, Saudi Arabia
| | | | | | - Zaki Manawar Eisa
- National Center for Diseases Prevention and Control, Jazan, Saudi Arabia
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21
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Rathmes G, Rumisha SF, Lucas TCD, Twohig KA, Python A, Nguyen M, Nandi AK, Keddie SH, Collins EL, Rozier JA, Gibson HS, Chestnutt EG, Battle KE, Humphreys GS, Amratia P, Arambepola R, Bertozzi-Villa A, Hancock P, Millar JJ, Symons TL, Bhatt S, Cameron E, Guerin PJ, Gething PW, Weiss DJ. Global estimation of anti-malarial drug effectiveness for the treatment of uncomplicated Plasmodium falciparum malaria 1991-2019. Malar J 2020; 19:374. [PMID: 33081784 PMCID: PMC7573874 DOI: 10.1186/s12936-020-03446-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/10/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Anti-malarial drugs play a critical role in reducing malaria morbidity and mortality, but their role is mediated by their effectiveness. Effectiveness is defined as the probability that an anti-malarial drug will successfully treat an individual infected with malaria parasites under routine health care delivery system. Anti-malarial drug effectiveness (AmE) is influenced by drug resistance, drug quality, health system quality, and patient adherence to drug use; its influence on malaria burden varies through space and time. METHODS This study uses data from 232 efficacy trials comprised of 86,776 infected individuals to estimate the artemisinin-based and non-artemisinin-based AmE for treating falciparum malaria between 1991 and 2019. Bayesian spatiotemporal models were fitted and used to predict effectiveness at the pixel-level (5 km × 5 km). The median and interquartile ranges (IQR) of AmE are presented for all malaria-endemic countries. RESULTS The global effectiveness of artemisinin-based drugs was 67.4% (IQR: 33.3-75.8), 70.1% (43.6-76.0) and 71.8% (46.9-76.4) for the 1991-2000, 2006-2010, and 2016-2019 periods, respectively. Countries in central Africa, a few in South America, and in the Asian region faced the challenge of lower effectiveness of artemisinin-based anti-malarials. However, improvements were seen after 2016, leaving only a few hotspots in Southeast Asia where resistance to artemisinin and partner drugs is currently problematic and in the central Africa where socio-demographic challenges limit effectiveness. The use of artemisinin-based combination therapy (ACT) with a competent partner drug and having multiple ACT as first-line treatment choice sustained high levels of effectiveness. High levels of access to healthcare, human resource capacity, education, and proximity to cities were associated with increased effectiveness. Effectiveness of non-artemisinin-based drugs was much lower than that of artemisinin-based with no improvement over time: 52.3% (17.9-74.9) for 1991-2000 and 55.5% (27.1-73.4) for 2011-2015. Overall, AmE for artemisinin-based and non-artemisinin-based drugs were, respectively, 29.6 and 36% below clinical efficacy as measured in anti-malarial drug trials. CONCLUSIONS This study provides evidence that health system performance, drug quality and patient adherence influence the effectiveness of anti-malarials used in treating uncomplicated falciparum malaria. These results provide guidance to countries' treatment practises and are critical inputs for malaria prevalence and incidence models used to estimate national level malaria burden.
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Affiliation(s)
- Giulia Rathmes
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Susan F Rumisha
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Telethon Kids Institute, Perth, Australia.
| | - Tim C D Lucas
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Katherine A Twohig
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Andre Python
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Center for Data Science, Zhejiang University, Hangzhou, 310058, China
| | - Michele Nguyen
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Anita K Nandi
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Suzanne H Keddie
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Emma L Collins
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Jennifer A Rozier
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Harry S Gibson
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Elisabeth G Chestnutt
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Katherine E Battle
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Georgina S Humphreys
- WorldWide Anti-Malarial Resistance Network (WWARN), Oxford, UK
- Infectious Diseases Data Observatory (IDDO), Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Punam Amratia
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Rohan Arambepola
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Amelia Bertozzi-Villa
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Institute for Disease Modeling, Bellevue, WA, USA
| | - Penelope Hancock
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Justin J Millar
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Tasmin L Symons
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Ewan Cameron
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Telethon Kids Institute, Perth, Australia
- Curtin University, Perth, Australia
| | - Philippe J Guerin
- WorldWide Anti-Malarial Resistance Network (WWARN), Oxford, UK
- Infectious Diseases Data Observatory (IDDO), Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Peter W Gething
- Telethon Kids Institute, Perth, Australia
- Curtin University, Perth, Australia
| | - Daniel J Weiss
- Malaria Atlas Project, Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Telethon Kids Institute, Perth, Australia
- Curtin University, Perth, Australia
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22
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Noviyanti R, Miotto O, Barry A, Marfurt J, Siegel S, Thuy-Nhien N, Quang HH, Anggraeni ND, Laihad F, Liu Y, Sumiwi ME, Trimarsanto H, Coutrier F, Fadila N, Ghanchi N, Johora FT, Puspitasari AM, Tavul L, Trianty L, Utami RAS, Wang D, Wangchuck K, Price RN, Auburn S. Implementing parasite genotyping into national surveillance frameworks: feedback from control programmes and researchers in the Asia-Pacific region. Malar J 2020; 19:271. [PMID: 32718342 PMCID: PMC7385952 DOI: 10.1186/s12936-020-03330-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/09/2020] [Indexed: 01/13/2023] Open
Abstract
The Asia-Pacific region faces formidable challenges in achieving malaria elimination by the proposed target in 2030. Molecular surveillance of Plasmodium parasites can provide important information on malaria transmission and adaptation, which can inform national malaria control programmes (NMCPs) in decision-making processes. In November 2019 a parasite genotyping workshop was held in Jakarta, Indonesia, to review molecular approaches for parasite surveillance and explore ways in which these tools can be integrated into public health systems and inform policy. The meeting was attended by 70 participants from 8 malaria-endemic countries and partners of the Asia Pacific Malaria Elimination Network. The participants acknowledged the utility of multiple use cases for parasite genotyping including: quantifying the prevalence of drug resistant parasites, predicting risks of treatment failure, identifying major routes and reservoirs of infection, monitoring imported malaria and its contribution to local transmission, characterizing the origins and dynamics of malaria outbreaks, and estimating the frequency of Plasmodium vivax relapses. However, the priority of each use case varies with different endemic settings. Although a one-size-fits-all approach to molecular surveillance is unlikely to be applicable across the Asia-Pacific region, consensus on the spectrum of added-value activities will help support data sharing across national boundaries. Knowledge exchange is needed to establish local expertise in different laboratory-based methodologies and bioinformatics processes. Collaborative research involving local and international teams will help maximize the impact of analytical outputs on the operational needs of NMCPs. Research is also needed to explore the cost-effectiveness of genetic epidemiology for different use cases to help to leverage funding for wide-scale implementation. Engagement between NMCPs and local researchers will be critical throughout this process.
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Affiliation(s)
| | - Olivo Miotto
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alyssa Barry
- School of Medicine, Deakin University, Geelong, VIC, Australia
- Burnet Institute, Melbourne, VIC, Australia
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Sasha Siegel
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Nguyen Thuy-Nhien
- Centre for Tropical Medicine, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Huynh Hong Quang
- Institute of Malariology, Parasitology and Entomology, Quy Nhon, Vietnam
| | | | | | - Yaobao Liu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu Province, China
| | | | | | - Farah Coutrier
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Nadia Fadila
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Najia Ghanchi
- Pathology, Aga Khan University Hospital, Karachi, Pakistan
| | - Fatema Tuj Johora
- Infectious Diseases Division, International Centre for Diarrheal Diseases Research, Bangladesh Mohakhali, Dhaka, Bangladesh
| | | | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Leily Trianty
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | | | - Duoquan Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Kesang Wangchuck
- Royal Center for Disease Control, Department of Public Health, Ministry of Health, Thimphu, Bhutan
| | - Ric N Price
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sarah Auburn
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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23
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She D, Wang Z, Liang Q, Lu L, Huang Y, Zhang K, An D, Wu J. Polymorphisms of pfcrt, pfmdr1, and K13-propeller genes in imported falciparum malaria isolates from Africa in Guizhou province, China. BMC Infect Dis 2020; 20:513. [PMID: 32677899 PMCID: PMC7364468 DOI: 10.1186/s12879-020-05228-8] [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: 02/20/2019] [Accepted: 07/03/2020] [Indexed: 12/30/2022] Open
Abstract
Background Imported falciparum malaria from Africa has become a key public health challenge in Guizhou Province since 2012. Understanding the polymorphisms of molecular markers of drug resistance can guide selection of antimalarial drugs for the treatment of malaria. This study was aimed to analyze the polymorphisms of pfcrt, pfmdr1, and K13-propeller among imported falciparum malaria cases in Guizhou Province, China. Method Fifty-five imported falciparum malaria cases in Guizhou Province during 2012–2016 were included in this study. Their demographic information and filter paper blood samples were collected. Genomic DNA of Plasmodium falciparum was extracted from the blood samples, and polymorphisms of pfcrt, pfmdr1, and K13-propeller were analyzed with nested PCR amplification followed by sequencing. Data were analyzed with the SPSS17.0 software. Results The prevalence of pfcrt K76T, pfmdr1 N86Y, and pfmdr1 Y184F mutation was 56.6, 22.2, and 72.2%, respectively, in imported falciparum malaria cases in Guizhou Province. We detected two mutant haplotypes of pfcrt, IET and MNT, with IET being more commonly found (54.7%), and five mutant haplotypes of pfmdr1, of which NFD was the most frequent (53.7%). There were totally 10 combined haplotypes of pfcrt and pfmdr1, of which the haplotype IETNFD possessed a predominance of 28.8%. In addition, three nonsynonymous mutations (S459T, C469F, and V692L) and two synonymous mutations (R471R and V589V) were detected in K13-propeller, all having prevalence less than 6.0%. In particular, a candidate K13 resistance mutation, C469F, was identified for the first time from Democratic Republic of the Congo with the prevalence of 2.0%. Conclusions The high prevalence of IET haplotype of pfcrt and NFD haplotype of pfmdr1 suggests the presence of chloroquine, artemether/lumefantrine, and dihydroartemisinin/piperaquine resistance in these cases. Therefore cautions should be made to artemisinin therapy for P. falciparum in Africa. Continuous monitoring of anti-malarial drug efficacy in imported malaria cases is helpful for optimizing antimalarial drug therapy in Guizhou Province, China.
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Affiliation(s)
- Danya She
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University; Department of Parasitology; Provincial Key Laboratory of Modern Pathogen Biology, Guizhou Medical University, Guiyang, 550025, China.,Guizhou Provincial Center for Disease Control and Prevention, Guiyang, 550004, China
| | - Zhengyan Wang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University; Department of Parasitology; Provincial Key Laboratory of Modern Pathogen Biology, Guizhou Medical University, Guiyang, 550025, China
| | - Qiuguo Liang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University; Department of Parasitology; Provincial Key Laboratory of Modern Pathogen Biology, Guizhou Medical University, Guiyang, 550025, China
| | - Lidan Lu
- Guizhou Provincial Center for Disease Control and Prevention, Guiyang, 550004, China
| | - Yuting Huang
- Guizhou Provincial Center for Disease Control and Prevention, Guiyang, 550004, China
| | - Ke Zhang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University; Department of Parasitology; Provincial Key Laboratory of Modern Pathogen Biology, Guizhou Medical University, Guiyang, 550025, China
| | - Dong An
- Guizhou Provincial Center for Disease Control and Prevention, Guiyang, 550004, China
| | - Jiahong Wu
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University; Department of Parasitology; Provincial Key Laboratory of Modern Pathogen Biology, Guizhou Medical University, Guiyang, 550025, China.
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24
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Ansbro MR, Jacob CG, Amato R, Kekre M, Amaratunga C, Sreng S, Suon S, Miotto O, Fairhurst RM, Wellems TE, Kwiatkowski DP. Development of copy number assays for detection and surveillance of piperaquine resistance associated plasmepsin 2/3 copy number variation in Plasmodium falciparum. Malar J 2020; 19:181. [PMID: 32404110 PMCID: PMC7218657 DOI: 10.1186/s12936-020-03249-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/29/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Long regarded as an epicenter of drug-resistant malaria, Southeast Asia continues to provide new challenges to the control of Plasmodium falciparum malaria. Recently, resistance to the artemisinin combination therapy partner drug piperaquine has been observed in multiple locations across Southeast Asia. Genetic studies have identified single nucleotide polymorphisms as well as copy number variations in the plasmepsin 2 and plasmepsin 3 genes, which encode haemoglobin-degrading proteases that associate with clinical and in vitro piperaquine resistance. RESULTS To accurately and quickly determine the presence of copy number variations in the plasmepsin 2/3 genes in field isolates, this study developed a quantitative PCR assay using TaqMan probes. Copy number estimates were validated using a separate SYBR green-based quantitative PCR assay as well as a novel PCR-based breakpoint assay to detect the hybrid gene product. Field samples from 2012 to 2015 across three sites in Cambodia were tested using DNA extracted from dried blood spots and whole blood to monitor the extent of plasmepsin 2/3 gene amplifications, as well as amplifications in the multidrug resistance transporter 1 gene (pfmdr1), a marker of mefloquine resistance. This study found high concordance across all methods of copy number detection. For samples derived from dried blood spots, a success rate greater than 80% was found in each assay, with more recent samples performing better. Evidence of extensive plasmepsin 2/3 copy number amplifications was observed in Pursat (94%, 2015) (Western Cambodia) and Preah Vihear (87%, 2014) (Northern Cambodia), and lower levels in Ratanakiri (16%, 2014) (Eastern Cambodia). A shift was observed from two copies of plasmepsin 2 in Pursat in 2013 to three copies in 2014-2015 (25% to 64%). Pfmdr1 amplifications were absent in all samples from Preah Vihear and Ratanakiri in 2014 and absent in Pursat in 2015. CONCLUSIONS The multiplex TaqMan assay is a robust tool for monitoring both plasmepsin 2/3 and pfmdr1 copy number variations in field isolates, and the SYBR-green and breakpoint assays are useful for monitoring plasmepsin 2/3 amplifications. This study shows increasing levels of plasmepsin 2 copy numbers across Cambodia from 2012 to 2015 and a complete reversion of multicopy pfmdr1 parasites to single copy parasites in all study locations.
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Affiliation(s)
- Megan R Ansbro
- Wellcome Sanger Institute, Hinxton, UK.
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
| | | | | | | | - Chanaki Amaratunga
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Sokunthea Sreng
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Seila Suon
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Genomics and Global Health, Wellcome Centre for Human Genetics, Oxford, UK
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Thomas E Wellems
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Dominic P Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK
- Centre for Genomics and Global Health, Wellcome Centre for Human Genetics, Oxford, UK
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25
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Jiang T, Chen XS. Outcome Impacts Due to Pathogen-Specific Antimicrobial Resistance: A Narrative Review of Published Literature. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17041395. [PMID: 32098182 PMCID: PMC7068360 DOI: 10.3390/ijerph17041395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 01/31/2020] [Accepted: 02/19/2020] [Indexed: 12/19/2022]
Abstract
Antimicrobial resistance (AMR) has become a global threat to not only public health impacts but also clinical and economic outcomes. During the past decades, there have been many studies focusing on surveillance, mechanisms, and diagnostics of AMR in infectious diseases but the impacts on public health, clinical and economic outcomes due to emergence of these AMRs are rarely studied and reported. This review was aimed to summarize the findings from published studies to report the outcome impacts due to AMR of malaria, tuberculosis and HIV and briefly discuss the implications for application to other infectious diseases. PubMed/Medline and Google Scholar databases were used for search of empirical and peer-reviewed papers reporting public health, clinical and economic outcomes due to AMR of malaria, tuberculosis and HIV. Papers published through 1 December 2019 were included in this review. A total of 76 studies were included for this review, including 16, 49 and 11 on public health, clinical and economic outcomes, respectively. The synthesized data indicated that the emergence and spread of AMR of malaria, tuberculosis and HIV have resulted in adverse public health, clinical and economic outcomes. AMR of malaria, tuberculosis and HIV results in significant adverse impacts on public health, clinical and economic outcomes. Evidence from this review suggests the needs to consider the similar studies for other infectious diseases.
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Affiliation(s)
- Tingting Jiang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China;
- National Center for STD Control, Chinese Center for Disease Control and Prevention, Nanjing 210042, China
| | - Xiang-Sheng Chen
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China;
- National Center for STD Control, Chinese Center for Disease Control and Prevention, Nanjing 210042, China
- Correspondence: ; Tel.: +86-25-8547-8901
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Naing C, Whittaker MA, Htet NH, Aye SN, Mak JW. Efficacy of antimalarial drugs for treatment of uncomplicated falciparum malaria in Asian region: A network meta-analysis. PLoS One 2019; 14:e0225882. [PMID: 31856172 PMCID: PMC6922314 DOI: 10.1371/journal.pone.0225882] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 11/14/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The WHO recommends artemisinin-based combination therapies (ACTs) for the treatment of uncomplicated falciparum malaria. Hence, monitoring the efficacy of antimalarial drugs is a key component of malaria control and elimination. The published randomized trials that assessed comparisons of ACTs for treating uncomplicated falciparum malaria reported conflicting results in treatment efficacy. A network meta-analysis is an extension of pairwise meta-analysis that can synthesize evidence simultaneously from both direct and indirect treatment comparisons. The objective was to synthesize evidence on the comparative efficacy of antimalarial drugs for treatment of uncomplicated falciparum malaria in Asian region. METHODS Relevant randomized trials that assessed efficacy of antimalarial drugs for patients having uncomplicated falciparum malaria in Asian region were searched in health-related databases. We evaluated the methodological quality of the included studies with the Cochrane risk of bias tool. Main outcome was treatment success at day 28 as determined by the absence of parasiteamia. We performed network meta-analysis of the interventions in the trials, and assessed the overall quality of evidence using the GRADE approach. RESULTS Seventeen randomized trials (n = 5043) were included in this network meta-analysis study. A network geometry was formed with 14 antimalarial treatment options such as artemether-lumefantrine (AL), artemisinin-piperaquine, artesunate-amodiaquine, artesunate-mefloquine (ASMQ), artesunate-chloroquine, artesunate-mefloquine home treatment, artesunate-mefloquine 2-day course, artesunate plus sulfadoxine-pyrimethamine, chloroquine, dihydroartemisinin-piperaquine (DHP), dihydroartemisinin-piperaquine home treatment, dihydroartemisinin-piperaquine 4-day course, dihydroartemisinin-piperaquine and added artesunate, sulfadoxine-pyrimethamine. A maximum number of trials included was DHP compared to ASMQ (n = 5). In general, DHP had better efficacy than AL at day 28 (DHP vs AL: OR 2.5, 95%CI:1.08-5.8). There is low certainty evidence due to limited number of studies and small trials. DISCUSSION/ CONCLUSIONS The findings suggest the superiority of DHP (3-day course) to AL and other comparator ACTs are with the overall low/very low quality of evidence judgements. Moreover, one drug regimen is better than another is only if current drug-resistance patterns are at play. For example, the AL might be better than DHP in areas where both artemisinin and piperaquine resistance patterns are prevalent. For substantiation, well-designed larger trials from endemic countries are needed. In the light of benefit versus harm concept, future analysis with safety information is recommended.
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Affiliation(s)
- Cho Naing
- International Medical University, Kuala Lumpur, Malaysia
- Faculty of Tropical Heath and Medicine, James Cook University, Queensland, Australia
| | - Maxine A Whittaker
- Faculty of Tropical Heath and Medicine, James Cook University, Queensland, Australia
| | | | - Saint Nway Aye
- International Medical University, Kuala Lumpur, Malaysia
| | - Joon Wah Mak
- International Medical University, Kuala Lumpur, Malaysia
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Chhibber-Goel J, Sharma A. Profiles of Kelch mutations in Plasmodium falciparum across South Asia and their implications for tracking drug resistance. Int J Parasitol Drugs Drug Resist 2019; 11:49-58. [PMID: 31606696 PMCID: PMC6796718 DOI: 10.1016/j.ijpddr.2019.10.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 09/27/2019] [Accepted: 10/01/2019] [Indexed: 11/16/2022]
Abstract
Artemisinin-based combination therapy (ACT) offers highly successful treatment of malaria. Emergence and spread of Plasmodium falciparum (Pf) parasites with decreased susceptibility to ACT in South-East Asia has caused concern worldwide. The current accepted criteria to assess artemisinin (ART) resistance relies upon data on treatment failure, delayed parasite clearance at day 3 (DPC3), parasite clearance half-life (PCHL) and in-vitro/ex-vivo ring stage survival assays (RSAs). Interestingly, some studies suggest that DPC3 does not provide a distinct separation between ART sensitive/resistant strains, and RSA differences may also be inconclusive. More recently, recrudescence of ART treated Pf, independent of the presence of Kelch 13 (K13) mutation (C580Y), has been reported in the monkey malaria model suggesting that genes other than K13 like coronin, dhps, dhfr, crt, mdr1 and plasmepsin1 may contribute towards ACT failure. Here we have collated the distribution of K13 mutants from Pf strains in South Asia. A total of fifty Pf-K13 mutations have been studied for ART resistance in South Asia of which nine have been validated while eleven are potentials for ART resistance. The remaining thirty K13 mutations have been reported from various locations in South Asia but lack corroborative clinical data on ART resistance/ACT failure. Of the fifty, fourteen K13 mutations have been identified in India including four novel mutations (S549Y, G625R, N657H, D702N). Structural mapping of these K13 mutations does not offer any coherent explanation for their contribution towards ART resistance as they are scattered in the K13 structure. Thus, K13 mutations likely provide only a partial synopsis, and we propose that all suspect cases of ACT failure be assessed by: 1) DPC3, 2) PCHL, 3) in-vitro/ex-vivo RSAs and 4) GWAS data in an effort to annotate the resistance status of the parasites. These efforts may help in surveillance and containment of ART resistance/ACT failure in South Asia.
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Affiliation(s)
- Jyoti Chhibber-Goel
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.
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Popovici J, Pierce-Friedrich L, Kim S, Bin S, Run V, Lek D, Hee KHD, Lee Soon-U L, Cannon MV, Serre D, Menard D. Recrudescence, Reinfection, or Relapse? A More Rigorous Framework to Assess Chloroquine Efficacy for Plasmodium vivax Malaria. J Infect Dis 2019; 219:315-322. [PMID: 30102351 DOI: 10.1093/infdis/jiy484] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 08/07/2018] [Indexed: 11/14/2022] Open
Abstract
Background Plasmodium vivax resistance to chloroquine (CQ) has been reported worldwide, although the World Health Organization clinical drug efficacy studies protocol does not permit classification of patient outcomes. Methods We enrolled 40 patients with P. vivax malaria in northeastern Cambodia, where >17% treatment failures were previously reported. Patients were treated with CQ (30 mg/kg) and followed for 2 months, with frequent clinical examination and capillary blood sample collection for microscopy, molecular parasite detection and genotyping, and drug concentration measurements. Reinfections were prevented by relocating patients to a transmission-free area. Results P. vivax parasites were eliminated in all patients by day 3. Genomic analyses revealed that all clones in polyclonal infections were cleared at the same rate, indicating their equal susceptibility to CQ. CQ blood concentrations were below the therapeutic level in all recurrent infections (24 of 40 patients), which were efficiently cleared by a second course of CQ treatment. Genotyping (128 SNPs barcode) and sequences of entire parasite genome (Whole-Genome Sequencing, Illumina) indicated that two thirds (6 of 8) of the recurrent parasites resulted from heterologous relapses whose 50% are from by sibling/recombinant clones. Conclusions No evidence of CQ resistance was observed. Our data suggest that P. vivax antimalarial drug resistance is likely overestimated and that the current guidelines for clinical drug studies of P. vivax malaria need to be revised.
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Affiliation(s)
- Jean Popovici
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh
| | | | - Saorin Kim
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh
| | - Sophalai Bin
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh
| | - Vorleak Run
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh
| | - Dysoley Lek
- National Center for Malaria Control, Phnom Penh, Cambodia
| | | | | | - Matthew V Cannon
- Genomic Medicine Institute, Cleveland Clinic, Ohio.,Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore
| | - David Serre
- Genomic Medicine Institute, Cleveland Clinic, Ohio.,Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore
| | - Didier Menard
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh.,Malaria Genetics and Resistance Group, Biology of Host-Parasite Interactions Unit, Institut Pasteur, France
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29
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Zhao Y, Liu Z, Soe MT, Wang L, Soe TN, Wei H, Than A, Aung PL, Li Y, Zhang X, Hu Y, Wei H, Zhang Y, Burgess J, Siddiqui FA, Menezes L, Wang Q, Kyaw MP, Cao Y, Cui L. Genetic Variations Associated with Drug Resistance Markers in Asymptomatic Plasmodium falciparum Infections in Myanmar. Genes (Basel) 2019; 10:genes10090692. [PMID: 31505774 PMCID: PMC6770986 DOI: 10.3390/genes10090692] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 08/31/2019] [Accepted: 09/04/2019] [Indexed: 12/30/2022] Open
Abstract
The emergence and spread of drug resistance is a problem hindering malaria elimination in Southeast Asia. In this study, genetic variations in drug resistance markers of Plasmodium falciparum were determined in parasites from asymptomatic populations located in three geographically dispersed townships of Myanmar by PCR and sequencing. Mutations in dihydrofolate reductase (pfdhfr), dihydropteroate synthase (pfdhps), chloroquine resistance transporter (pfcrt), multidrug resistance protein 1 (pfmdr1), multidrug resistance-associated protein 1 (pfmrp1), and Kelch protein 13 (k13) were present in 92.3%, 97.6%, 84.0%, 98.8%, and 68.3% of the parasites, respectively. The pfcrt K76T, pfmdr1 N86Y, pfmdr1 I185K, and pfmrp1 I876V mutations were present in 82.7%, 2.5%, 87.5%, and 59.8% isolates, respectively. The most prevalent haplotypes for pfdhfr, pfdhps, pfcrt and pfmdr1 were 51I/59R/108N/164L, 436A/437G/540E/581A, 74I/75E/76T/220S/271E/326N/356T/371I, and 86N/130E/184Y/185K/1225V, respectively. In addition, 57 isolates had three different point mutations (K191T, F446I, and P574L) and three types of N-terminal insertions (N, NN, NNN) in the k13 gene. In total, 43 distinct haplotypes potentially associated with multidrug resistance were identified. These findings demonstrate a high prevalence of multidrug-resistant P. falciparum in asymptomatic infections from diverse townships in Myanmar, emphasizing the importance of targeting asymptomatic infections to prevent the spread of drug-resistant P.falciparum.
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Affiliation(s)
- Yan Zhao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Ziling Liu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Myat Thu Soe
- Myanmar Health Network Organization, Yangon 11211, Myanmar.
| | - Lin Wang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Than Naing Soe
- Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw 15011, Myanmar.
| | - Huanping Wei
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Aye Than
- Myanmar Health Network Organization, Yangon 11211, Myanmar.
| | - Pyae Linn Aung
- Myanmar Health Network Organization, Yangon 11211, Myanmar.
| | - Yuling Li
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Xuexing Zhang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Yubing Hu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Haichao Wei
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Yangminghui Zhang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Jessica Burgess
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Tampa, FL 33612, USA.
| | - Faiza A Siddiqui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Tampa, FL 33612, USA.
| | - Lynette Menezes
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Tampa, FL 33612, USA.
| | - Qinghui Wang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | | | - Yaming Cao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang 110122, China.
| | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Tampa, FL 33612, USA.
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Prevalence of Plasmodium falciparum Pfcrt and Pfmdr1 alleles in settings with different levels of Plasmodium vivax co-endemicity in Ethiopia. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2019; 11:8-12. [PMID: 31539706 PMCID: PMC6796752 DOI: 10.1016/j.ijpddr.2019.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 08/28/2019] [Accepted: 09/09/2019] [Indexed: 12/27/2022]
Abstract
Plasmodium falciparum and P. vivax co-exist at different endemicity levels across Ethiopia. For over two decades Artemether-Lumefantrine (AL) is the first line treatment for uncomplicated P. falciparum, while chloroquine (CQ) is still used to treat P. vivax. It is currently unclear whether a shift from CQ to AL for P. falciparum treatment has implications for AL efficacy and results in a reversal of mutations in genes associated to CQ resistance, given the high co-endemicity of the two species and the continued availability of CQ for the treatment of P. vivax. This study thus assessed the prevalence of Pfcrt-K76T and Pfmdr1-N86Y point mutations in P. falciparum. 18S RNA gene based nested PCR confirmed P. falciparum samples (N = 183) collected through community and health facility targeted cross-sectional surveys from settings with varying P. vivax and P. falciparum endemicity were used. The proportion of Plasmodium infections that were P. vivax was 62.2% in Adama, 41.4% in Babile, 30.0% in Benishangul-Gumuz to 6.9% in Gambella. The Pfcrt-76T mutant haplotype was observed more from samples with higher endemicity of P. vivax as being 98.4% (61/62), 100% (31/31), 65.2% (15/23) and 41.5% (22/53) in samples from Adama, Babile, Benishangul-Gumuz and Gambella, respectively. However, a relatively higher proportion of Pfmdr1-N86 allele (77.3–100%) were maintained in all sites. The observed high level of the mutant Pfcrt-76T allele in P. vivax co-endemic sites might require that utilization of CQ needs to be re-evaluated in settings co-endemic for the two species. A country-wide assessment is recommended to clarify the implication of the observed level of variation in drug resistance markers on the efficacy of AL-based treatment against uncomplicated P. falciparum malaria.
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Hamilton WL, Amato R, van der Pluijm RW, Jacob CG, Quang HH, Thuy-Nhien NT, Hien TT, Hongvanthong B, Chindavongsa K, Mayxay M, Huy R, Leang R, Huch C, Dysoley L, Amaratunga C, Suon S, Fairhurst RM, Tripura R, Peto TJ, Sovann Y, Jittamala P, Hanboonkunupakarn B, Pukrittayakamee S, Chau NH, Imwong M, Dhorda M, Vongpromek R, Chan XHS, Maude RJ, Pearson RD, Nguyen T, Rockett K, Drury E, Gonçalves S, White NJ, Day NP, Kwiatkowski DP, Dondorp AM, Miotto O. Evolution and expansion of multidrug-resistant malaria in southeast Asia: a genomic epidemiology study. THE LANCET. INFECTIOUS DISEASES 2019; 19:943-951. [PMID: 31345709 PMCID: PMC6715858 DOI: 10.1016/s1473-3099(19)30392-5] [Citation(s) in RCA: 190] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 06/15/2019] [Accepted: 06/20/2019] [Indexed: 11/16/2022]
Abstract
BACKGROUND A multidrug-resistant co-lineage of Plasmodium falciparum malaria, named KEL1/PLA1, spread across Cambodia in 2008-13, causing high rates of treatment failure with the frontline combination therapy dihydroartemisinin-piperaquine. Here, we report on the evolution and spread of KEL1/PLA1 in subsequent years. METHODS For this genomic epidemiology study, we analysed whole genome sequencing data from P falciparum clinical samples collected from patients with malaria between 2007 and 2018 from Cambodia, Laos, northeastern Thailand, and Vietnam, through the MalariaGEN P falciparum Community Project. Previously unpublished samples were provided by two large-scale multisite projects: the Tracking Artemisinin Resistance Collaboration II (TRAC2) and the Genetic Reconnaissance in the Greater Mekong Subregion (GenRe-Mekong) project. By investigating genome-wide relatedness between parasites, we inferred patterns of shared ancestry in the KEL1/PLA1 population. FINDINGS We analysed 1673 whole genome sequences that passed quality filters, and determined KEL1/PLA1 status in 1615. Before 2009, KEL1/PLA1 was only found in western Cambodia; by 2016-17 its prevalence had risen to higher than 50% in all of the surveyed countries except for Laos. In northeastern Thailand and Vietnam, KEL1/PLA1 exceeded 80% of the most recent P falciparum parasites. KEL1/PLA1 parasites maintained high genetic relatedness and low diversity, reflecting a recent common origin. Several subgroups of highly related parasites have recently emerged within this co-lineage, with diverse geographical distributions. The three largest of these subgroups (n=84, n=79, and n=47) mostly emerged since 2016 and were all present in Cambodia, Laos, and Vietnam. These expanding subgroups carried new mutations in the crt gene, which arose on a specific genetic background comprising multiple genomic regions. Four newly emerging crt mutations were rare in the early period and became more prevalent by 2016-17 (Thr93Ser, rising to 19·8%; His97Tyr to 11·2%; Phe145Ile to 5·5%; and Ile218Phe to 11·1%). INTERPRETATION After emerging and circulating for several years within Cambodia, the P falciparum KEL1/PLA1 co-lineage diversified into multiple subgroups and acquired new genetic features, including novel crt mutations. These subgroups have rapidly spread into neighbouring countries, suggesting enhanced fitness. These findings highlight the urgent need for elimination of this increasingly drug-resistant parasite co-lineage, and the importance of genetic surveillance in accelerating malaria elimination efforts. FUNDING Wellcome Trust, Bill & Melinda Gates Foundation, UK Medical Research Council, and UK Department for International Development.
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Affiliation(s)
- William L Hamilton
- Wellcome Sanger Institute, Hinxton, UK; Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK; MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Rob W van der Pluijm
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Huynh Hong Quang
- Institute of Malariology, Parasitology and Entomology, Quy Nhon, Vietnam
| | | | - Tran Tinh Hien
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | | | | | - Mayfong Mayxay
- Institute of Research and Education Development, University of Health Sciences, Vientiane, Laos; Lao-Oxford-Mahosot Hospital Wellcome Trust Research Unit (LOMWRU), Vientiane, Laos
| | - Rekol Huy
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Rithea Leang
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Cheah Huch
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Lek Dysoley
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Chanaki Amaratunga
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Seila Suon
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Rupam Tripura
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Thomas J Peto
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Yok Sovann
- Provincial Health Department, Pailin, Cambodia
| | | | | | - Sasithon Pukrittayakamee
- Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; The Royal Society of Thailand, Bangkok, Thailand
| | | | - Mallika Imwong
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Mehul Dhorda
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK; Worldwide Antimalarial Resistance Network (WWARN), Asia Regional Centre, Bangkok, Thailand
| | - Ranitha Vongpromek
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Worldwide Antimalarial Resistance Network (WWARN), Asia Regional Centre, Bangkok, Thailand
| | - Xin Hui S Chan
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Richard J Maude
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK; Harvard TH Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Richard D Pearson
- Wellcome Sanger Institute, Hinxton, UK; MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - T Nguyen
- Wellcome Sanger Institute, Hinxton, UK
| | - Kirk Rockett
- Wellcome Sanger Institute, Hinxton, UK; Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | | | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nicholas P Day
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Dominic P Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK; MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK.
| | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK; MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK; Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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Plasmodium Genomics and Genetics: New Insights into Malaria Pathogenesis, Drug Resistance, Epidemiology, and Evolution. Clin Microbiol Rev 2019; 32:32/4/e00019-19. [PMID: 31366610 DOI: 10.1128/cmr.00019-19] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Protozoan Plasmodium parasites are the causative agents of malaria, a deadly disease that continues to afflict hundreds of millions of people every year. Infections with malaria parasites can be asymptomatic, with mild or severe symptoms, or fatal, depending on many factors such as parasite virulence and host immune status. Malaria can be treated with various drugs, with artemisinin-based combination therapies (ACTs) being the first-line choice. Recent advances in genetics and genomics of malaria parasites have contributed greatly to our understanding of parasite population dynamics, transmission, drug responses, and pathogenesis. However, knowledge gaps in parasite biology and host-parasite interactions still remain. Parasites resistant to multiple antimalarial drugs have emerged, while advanced clinical trials have shown partial efficacy for one available vaccine. Here we discuss genetic and genomic studies of Plasmodium biology, host-parasite interactions, population structures, mosquito infectivity, antigenic variation, and targets for treatment and immunization. Knowledge from these studies will advance our understanding of malaria pathogenesis, epidemiology, and evolution and will support work to discover and develop new medicines and vaccines.
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Sequential Open-Label Study of the Safety, Tolerability, and Pharmacokinetic Interactions between Dihydroartemisinin-Piperaquine and Mefloquine in Healthy Thai Adults. Antimicrob Agents Chemother 2019; 63:AAC.00060-19. [PMID: 31182525 PMCID: PMC6658739 DOI: 10.1128/aac.00060-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 05/25/2019] [Indexed: 11/26/2022] Open
Abstract
Artemisinin-based combination therapies (ACTs) have contributed substantially to the global decline in Plasmodium falciparum morbidity and mortality, but resistance to artemisinins and their partner drugs is increasing in Southeast Asia, threatening malaria control. New antimalarial compounds will not be generally available soon. Artemisinin-based combination therapies (ACTs) have contributed substantially to the global decline in Plasmodium falciparum morbidity and mortality, but resistance to artemisinins and their partner drugs is increasing in Southeast Asia, threatening malaria control. New antimalarial compounds will not be generally available soon. Combining three existing antimalarials in the form of triple ACTs, including dihydroartemisinin (DHA)-piperaquine + mefloquine, is a potential treatment option for multidrug-resistant Plasmodium falciparum malaria. In a sequential open-label study, healthy Thai volunteers were treated with DHA-piperaquine (120 to 960 mg), mefloquine (500 mg), and DHA-piperaquine + mefloquine (120 to 960 mg + 500 mg), and serial symptom questionnaires, biochemistry, full blood counts, pharmacokinetic profiles, and electrocardiographic measurements were performed. Fifteen healthy subjects were enrolled. There was no difference in the incidence or severity of adverse events between the three treatment arms. The slight prolongation in QTc (QT interval corrected for heart rate) associated with DHA-piperaquine administration did not increase after administration of DHA-piperaquine + mefloquine. The addition of mefloquine had no significant effect on the pharmacokinetic properties of piperaquine. However, coadministration of mefloquine significantly reduced the exposures to dihydroartemisinin for area under the concentration-time curve (−22.6%; 90% confidence interval [CI], −33.1, −10.4; P = 0.0039) and maximum concentration of drug in serum (−29.0%; 90% CI, −40.6, −15.1; P = 0.0079). Mefloquine can be added safely to dihydroartemisinin-piperaquine in malaria treatment. (This study has been registered at ClinicalTrials.gov under identifier NCT02324738.)
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Warsame M, Hassan AM, Hassan AH, Jibril AM, Khim N, Arale AM, Gomey AH, Nur ZS, Osman SM, Mohamed MS, Abdulrahman A, Yusuf FE, Amran JGH, Witkowski B, Ringwald P. High therapeutic efficacy of artemether-lumefantrine and dihydroartemisinin-piperaquine for the treatment of uncomplicated falciparum malaria in Somalia. Malar J 2019; 18:231. [PMID: 31296223 PMCID: PMC6624891 DOI: 10.1186/s12936-019-2864-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 07/03/2019] [Indexed: 11/26/2022] Open
Abstract
Background Artemether–lumefantrine (AL) and dihydroartemisinin–piperaquine (DHA/PPQ) are the recommended first- and second-line treatments, respectively, for uncomplicated falciparum malaria in Somalia. The studies reported here were conducted to assess the efficacy of these artemisinin-based combinations and the mutations in Plasmodium falciparum K13-propeller (Pfk13) domain and amplification in Pfplasmepsin 2 (Pfpm2) gene in Somalia. Methods One-arm prospective studies were conducted to assess the clinical and parasitological responses to DHA/PPQ and AL at two sites in 2016 and 2017, respectively, using the standard WHO protocol. The patterns of molecular markers associated with artemisinin and PPQ resistance were investigated for the first time in Somalia. Results A total of 339 patients were enrolled with 139 for AL and 200 for DHA/PPQ. With AL, no parasite recurrence was observed among patients treated at either site, corresponding to 100% clinical and parasitological responses. For DHA–PPQ, an adequate clinical and parasitological response rate > 97% was observed. All study patients on both treatments at both sites were parasite-free on day 3. Of the 138 samples with interpretable results for the polymorphism in Pfk13, only one (0.7%), from Bosaso, contained a non-synonymous mutation (R622I), which is not one of the known markers of artemisinin resistance. No Pfpm2 amplification was observed among the 135 samples with interpretable results. Conclusions AL and DHA/PPQ were highly effective in the treatment of uncomplicated falciparum malaria, and there was no evidence of resistance to artemisinin or PPQ. These two combinations are thus relevant in the chemotherapeutic strategy for malaria control in Somalia. Trial registration ACTRN12616001005448 (Jowhar DP study), ACTRN12616000553471 (Bosaso DP study), ACTRN12617001055392 (AL study in Bosaso and Jowhar)
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Affiliation(s)
- Marian Warsame
- Global Malaria Programme, World Health Organization, 20 Avenue Appia, 1211, Geneva 27, Switzerland. .,University of Gothenburg, Gothenburg, Sweden.
| | | | | | | | - Nimol Khim
- Malaria Molecular Epidemiology Unit, Pasteur Institute in Cambodia, Phnom Penh, Cambodia
| | | | | | | | | | | | | | | | | | - Benoit Witkowski
- Malaria Molecular Epidemiology Unit, Pasteur Institute in Cambodia, Phnom Penh, Cambodia.,Malaria Translational Research Unit, Pasteur Institute, Paris, France
| | - Pascal Ringwald
- Global Malaria Programme, World Health Organization, 20 Avenue Appia, 1211, Geneva 27, Switzerland
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Competing risk events in antimalarial drug trials in uncomplicated Plasmodium falciparum malaria: a WorldWide Antimalarial Resistance Network individual participant data meta-analysis. Malar J 2019; 18:225. [PMID: 31277713 PMCID: PMC6612160 DOI: 10.1186/s12936-019-2837-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 06/14/2019] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Therapeutic efficacy studies in uncomplicated Plasmodium falciparum malaria are confounded by new infections, which constitute competing risk events since they can potentially preclude/pre-empt the detection of subsequent recrudescence of persistent, sub-microscopic primary infections. METHODS Antimalarial studies typically report the risk of recrudescence derived using the Kaplan-Meier (K-M) method, which considers new infections acquired during the follow-up period as censored. Cumulative Incidence Function (CIF) provides an alternative approach for handling new infections, which accounts for them as a competing risk event. The complement of the estimate derived using the K-M method (1 minus K-M), and the CIF were used to derive the risk of recrudescence at the end of the follow-up period using data from studies collated in the WorldWide Antimalarial Resistance Network data repository. Absolute differences in the failure estimates derived using these two methods were quantified. In comparative studies, the equality of two K-M curves was assessed using the log-rank test, and the equality of CIFs using Gray's k-sample test (both at 5% level of significance). Two different regression modelling strategies for recrudescence were considered: cause-specific Cox model and Fine and Gray's sub-distributional hazard model. RESULTS Data were available from 92 studies (233 treatment arms, 31,379 patients) conducted between 1996 and 2014. At the end of follow-up, the median absolute overestimation in the estimated risk of cumulative recrudescence by using 1 minus K-M approach was 0.04% (interquartile range (IQR): 0.00-0.27%, Range: 0.00-3.60%). The overestimation was correlated positively with the proportion of patients with recrudescence [Pearson's correlation coefficient (ρ): 0.38, 95% Confidence Interval (CI) 0.30-0.46] or new infection [ρ: 0.43; 95% CI 0.35-0.54]. In three study arms, the point estimates of failure were greater than 10% (the WHO threshold for withdrawing antimalarials) when the K-M method was used, but remained below 10% when using the CIF approach, but the 95% confidence interval included this threshold. CONCLUSIONS The 1 minus K-M method resulted in a marginal overestimation of recrudescence that became increasingly pronounced as antimalarial efficacy declined, particularly when the observed proportion of new infection was high. The CIF approach provides an alternative approach for derivation of failure estimates in antimalarial trials, particularly in high transmission settings.
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Wongsrichanalai C, Kurdova-Mintcheva R, Palmer K. Current Malaria Situation in Asia-Oceania. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2019; 2013:45-56. [PMID: 31267492 DOI: 10.1007/978-1-4939-9550-9_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Asia-Oceania is a diverse region that comprises roughly 65% of the global population at risk for malaria. In 2016 WHO estimated the number of malaria cases across the Asia-Oceania to be 17 million, which is only a small part (8%) of the total global malaria burden, and the number of cases is shrinking rapidly. Most countries have brought their cases down to the point where elimination is in sight. Plasmodium vivax (P. vivax) is becoming the dominant malaria species in many of those countries, where malaria occurs in hot spots of transmission frequently along international borders. The challenge is now to concentrate on those areas. This chapter reviews the situation in various areas of the Region and focuses on a number of important issues, including the prevalence of P. vivax and drug-resistant malaria.
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Affiliation(s)
| | | | - Kevin Palmer
- Department of Tropical Medicine and Pharmacology, John A. Burns School of Medicine, Honolulu, HI, USA
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Verzier LH, Coyle R, Singh S, Sanderson T, Rayner JC. Plasmodium knowlesi as a model system for characterising Plasmodium vivax drug resistance candidate genes. PLoS Negl Trop Dis 2019; 13:e0007470. [PMID: 31158222 PMCID: PMC6564043 DOI: 10.1371/journal.pntd.0007470] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 06/13/2019] [Accepted: 05/15/2019] [Indexed: 12/29/2022] Open
Abstract
Plasmodium vivax causes the majority of malaria outside Africa, but is poorly understood at a cellular level partly due to technical difficulties in maintaining it in in vitro culture conditions. In the past decades, drug resistant P. vivax parasites have emerged, mainly in Southeast Asia, but while some molecular markers of resistance have been identified, none have so far been confirmed experimentally, which limits interpretation of the markers, and hence our ability to monitor and control the spread of resistance. Some of these potential markers have been identified through P. vivax genome-wide population genetic analyses, which highlighted genes under recent evolutionary selection in Southeast Asia, where chloroquine resistance is most prevalent. These genes could be involved in drug resistance, but no experimental proof currently exists to support this hypothesis. In this study, we used Plasmodium knowlesi, the most closely related species to P. vivax that can be cultured in human erythrocytes, as a model system to express P. vivax genes and test for their role in drug resistance. We adopted a strategy of episomal expression, and were able to express fourteen P. vivax genes, including two allelic variants of several hypothetical resistance genes. Their expression level and localisation were assessed, confirming cellular locations conjectured from orthologous species, and suggesting locations for several previously unlocalised proteins, including an apical location for PVX_101445. These findings establish P. knowlesi as a suitable model for P. vivax protein expression. We performed chloroquine and mefloquine drug assays, finding no significant differences in drug sensitivity: these results could be due to technical issues, or could indicate that these genes are not actually involved in drug resistance, despite being under positive selection pressure in Southeast Asia. These data confirm that in vitro P. knowlesi is a useful tool for studying P. vivax biology. Its close evolutionary relationship to P. vivax, high transfection efficiency, and the availability of markers for colocalisation, all make it a powerful model system. Our study is the first of its kind using P. knowlesi to study unknown P. vivax proteins and investigate drug resistance mechanisms.
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Affiliation(s)
- Lisa H. Verzier
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, United Kingdom
| | - Rachael Coyle
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, United Kingdom
| | - Shivani Singh
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, United Kingdom
| | - Theo Sanderson
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, United Kingdom
| | - Julian C. Rayner
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, United Kingdom
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Dahal P, Guerin PJ, Price RN, Simpson JA, Stepniewska K. Evaluating antimalarial efficacy in single-armed and comparative drug trials using competing risk survival analysis: a simulation study. BMC Med Res Methodol 2019; 19:107. [PMID: 31101088 PMCID: PMC6525412 DOI: 10.1186/s12874-019-0748-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 05/07/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Antimalarial efficacy studies in patients with uncomplicated Plasmodium falciparum are confounded by a new infection (a competing risk event) since this event can potentially preclude a recrudescent event (primary endpoint of interest). The current WHO guidelines recommend censoring competing risk events when deriving antimalarial efficacy. We investigated the impact of considering a new infection as a competing risk event on the estimation of antimalarial efficacy in single-armed and comparative drug trials using two simulation studies. METHODS The first simulation study explored differences in the estimates of treatment failure for areas of varying transmission intensities using the complement of the Kaplan-Meier (K-M) estimate and the Cumulative Incidence Function (CIF). The second simulation study extended this to a comparative drug efficacy trial for comparing the K-M curves using the log-rank test, and Gray's k-sample test for comparing the equality of CIFs. RESULTS The complement of the K-M approach produced larger estimates of cumulative treatment failure compared to the CIF method; the magnitude of which was correlated with the observed proportion of new infection and recrudescence. When the drug efficacy was 90%, the absolute overestimation in failure was 0.3% in areas of low transmission rising to 3.1% in the high transmission settings. In a scenario which is most likely to be observed in a comparative trial of antimalarials, where a new drug regimen is associated with an increased (or decreased) rate of recrudescences and new infections compared to an existing drug, the log-rank test was found to be more powerful to detect treatment differences compared to the Gray's k-sample test. CONCLUSIONS The CIF approach should be considered for deriving estimates of antimalarial efficacy, in high transmission areas or for failing drugs. For comparative studies of antimalarial treatments, researchers need to select the statistical test that is best suited to whether the rate or cumulative risk of recrudescence is the outcome of interest, and consider the potential differing prophylactic periods of the antimalarials being compared.
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Affiliation(s)
- Prabin Dahal
- WorldWide Antimalarial Resistance Network (WWARN), Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Philippe J. Guerin
- WorldWide Antimalarial Resistance Network (WWARN), Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Ric N. Price
- WorldWide Antimalarial Resistance Network (WWARN), Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Julie A. Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Kasia Stepniewska
- WorldWide Antimalarial Resistance Network (WWARN), Oxford, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
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Efficacy and resistance of different artemisinin-based combination therapies: a systematic review and network meta-analysis. Parasitol Int 2019; 74:101919. [PMID: 31015034 DOI: 10.1016/j.parint.2019.04.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/01/2019] [Accepted: 04/17/2019] [Indexed: 12/24/2022]
Abstract
BACKGROUND Malaria parasites have developed resistance to most of the known antimalarial drugs in clinical practice, with reports of artemisinin resistance emerging in South East Asia (SEA). We sort to find the status of artemisinin resistance and efficacy of different modalities of the current artemisinin-based combination therapies (ACTs). METHODS We carried out a systematic search in 11 electronic databases to identify in vivo studies published between 2001 and 2017 that reported artemisinin resistance. This was then followed by A network meta-analysis to compare the efficacy of different ACTs. Quality assessment was performed using the Cochrane Risk of Bias (ROB) tool for randomized controlled trials and National Institute of Health (NIH) tool for cross-sectional studies. The study protocol was registered in PROSPERO under number CRD42018087574. RESULTS With 8400 studies initially identified, 82 were eligible for qualitative and quantitative analysis. Artemisinin resistance was only reported in South East Asia. K13 mutation C580Y was the most abundant mutation associated with resistance having an abundance of 63.1% among all K13 mutations reported. Although the overall network meta-analysis had shown good performance of dihydroartemisinin piperaquine in the early years, a subgroup analysis of the recent years revealed a poor performance of the drug in relation to recrudescence, clinical failure and parasitological failure especially in the artemisinin resistant regions. CONCLUSION With report of high resistance and treatment failure against the leading artemisinin combination therapy in South East Asia, it is imperative that a new drug or a formulation is developed before further spread of resistance.
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Corpolongo A, Pisapia R, Oliva A, Giancola ML, Mencarini P, Bevilacqua N, Ghirga P, Mariano A, Vulcano A, Paglia MG, Nicastri E. Five cases of Plasmodium vivax malaria treated with artemisinin derivatives: the advantages of a unified approach to treatment. Infection 2019; 47:655-659. [PMID: 30809760 DOI: 10.1007/s15010-019-01286-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 02/19/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVES In endemic countries with a high level of chloroquine resistance, Plasmodium vivax malaria is associated with high morbidity and mortality. In these areas, the dihydroartemisinin-piperaquine combination resulted in clinical response, a more rapid clearance of parasitaemia, compared to chloroquine therapies, and reduction of recrudescence or reinfection. METHODS We describe five cases of Plasmodium vivax malaria in returning travelers treated with dihydroartemisinin-piperaquine. RESULTS All patients showed the early parasite clearance and no side effects. Our preliminary results suggest that the dihydroartemisinin-piperaquine combination is effective and safe even in imported cases. CONCLUSIONS A unified treatment policy using the artemisinin combination therapy should be adopted even in non-endemic countries and larger studies are underway to support this strategy.
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Affiliation(s)
- Angela Corpolongo
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Raffaella Pisapia
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy.
| | - Alessandra Oliva
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Maria Letizia Giancola
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Paola Mencarini
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Nazario Bevilacqua
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Piero Ghirga
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Andrea Mariano
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Antonella Vulcano
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Maria Grazia Paglia
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
| | - Emanuele Nicastri
- National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Via Portuense, 292, 00149, Rome, Italy
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Resistance to Artemisinin Combination Therapies (ACTs): Do Not Forget the Partner Drug! Trop Med Infect Dis 2019; 4:tropicalmed4010026. [PMID: 30717149 PMCID: PMC6473515 DOI: 10.3390/tropicalmed4010026] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/30/2019] [Accepted: 01/30/2019] [Indexed: 01/30/2023] Open
Abstract
Artemisinin-based combination therapies (ACTs) have become the mainstay for malaria treatment in almost all malaria endemic settings. Artemisinin derivatives are highly potent and fast acting antimalarials; but they have a short half-life and need to be combined with partner drugs with a longer half-life to clear the remaining parasites after a standard 3-day ACT regimen. When introduced, ACTs were highly efficacious and contributed to the steep decrease of malaria over the last decades. However, parasites with decreased susceptibility to artemisinins have emerged in the Greater Mekong Subregion (GMS), followed by ACTs’ failure, due to both decreased susceptibility to artemisinin and partner drug resistance. Therefore, there is an urgent need to strengthen and expand current resistance surveillance systems beyond the GMS to track the emergence or spread of artemisinin resistance. Great attention has been paid to the spread of artemisinin resistance over the last five years, since molecular markers of decreased susceptibility to artemisinin in the GMS have been discovered. However, resistance to partner drugs is critical, as ACTs can still be effective against parasites with decreased susceptibility to artemisinins, when the latter are combined with a highly efficacious partner drug. This review outlines the different mechanisms of resistance and molecular markers associated with resistance to partner drugs for the currently used ACTs. Strategies to improve surveillance and potential solutions to extend the useful therapeutic lifespan of the currently available malaria medicines are proposed.
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Mengue JB, Held J, Kreidenweiss A. AQ-13 - an investigational antimalarial drug. Expert Opin Investig Drugs 2019; 28:217-222. [DOI: 10.1080/13543784.2019.1560419] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Juliana Boex Mengue
- Institute of Tropical Medicine, University Hospital Tuebingen, Tuebingen,
Germany
| | - Jana Held
- Institute of Tropical Medicine, University Hospital Tuebingen, Tuebingen,
Germany
| | - Andrea Kreidenweiss
- Institute of Tropical Medicine, University Hospital Tuebingen, Tuebingen,
Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital,
Lambaréné, Gabon
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Assessment of drug resistance associated genetic diversity in Mauritanian isolates of Plasmodium vivax reveals limited polymorphism. Malar J 2018; 17:416. [PMID: 30409138 PMCID: PMC6225721 DOI: 10.1186/s12936-018-2548-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 10/24/2018] [Indexed: 01/09/2023] Open
Abstract
Background Plasmodium vivax is the predominant malaria species in northern Mauritania. Molecular data on P. vivax isolates circulating in West Africa are scarce. The present study analysed molecular markers associated with resistance to antifolates (Pvdhfr and Pvdhps), chloroquine (Pvmdr1), and artemisinin (Pvk12) in P. vivax isolates collected in two cities located in the Saharan zone of Mauritania. Methods Blood samples were obtained from P. vivax-infected patients recruited for chloroquine therapeutic efficacy study in 2013 and febrile patients spontaneously consulting health facilities in Nouakchott and Atar in 2015–2016. Fragments of Pvdhfr (codons 13, 33, 57, 58, 61, 117, and 174), Pvdhps (codons 382, 383, 512, 553, and 585), Pvmdr1 (codons 976 and 1076) and Pvk12 (codon 552) genes were amplified by PCR and sequenced. Results Most of the isolates in Nouakchott (126/154, 81.8%) and Atar (44/45, 97.8%) carried the wild-type Pvdhfr allelic variant (IPFSTSI). In Nouakchott, all mutants (28/154; 18.2%) had double Pvdhfr mutations in positions 58 and 61 (allelic variant IPFRMSI), whereas in Atar only 1 isolate was mutant (S117N, allelic variant IPFSTNI). The wild-type Pvdhps allelic variant (SAKAV) was found in all tested isolates (Nouakchott, n = 93; Atar, n = 37). Few isolates in Nouakchott (5/115, 4.3%) and Atar (3/79, 3.8%) had the mutant Pvmdr1 allele 976F or 1076L, but not both, including in pre-treatment isolates obtained from patients treated successfully with chloroquine. All isolates (59 in Nouakchott and 48 in Atar) carried the wild-type V552 allele in Pvk12. Conclusions Polymorphisms in Pvdhfr, Pvdhps, Pvmdr1, and Pvk12 were limited in P. vivax isolates collected recently in Nouakchott and Atar. Compared to the isolates collected in Nouakchott in 2007–2009, there was no evidence for selection of mutants. The presence of one, but not both, of the two potential markers of chloroquine resistance in Pvmdr1 in pre-treatment isolates did not influence the clinical outcome, putting into question the role of Pvmdr1 mutant alleles 976F and 1076L in treatment failure. Molecular surveillance is an important component of P. vivax malaria control programme in the Saharan zone of Mauritania to predict possible emergence of drug-resistant parasites.
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Cluster-randomized trial of monthly malaria prophylaxis versus focused screening and treatment: a study protocol to define malaria elimination strategies in Cambodia. Trials 2018; 19:558. [PMID: 30326952 PMCID: PMC6192281 DOI: 10.1186/s13063-018-2931-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 09/24/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria remains a critical public health problem in Southeast Asia despite intensive containment efforts. The continued spread of multi-drug-resistant Plasmodium falciparum has led to calls for malaria elimination on the Thai-Cambodian border. However, the optimal approach to elimination in difficult-to-reach border populations, such as the Military, remains unclear. METHODS/DESIGN A two-arm, cluster-randomized controlled, open-label pilot study is being conducted in military personnel and their families at focal endemic areas on the Thai-Cambodian border. The primary objective is to compare the effectiveness of monthly malaria prophylaxis (MMP) with dihydroartemisinin-piperaquine and weekly primaquine for 12 weeks compared with focused screening and treating (FSAT) following current Cambodian national treatment guidelines. Eight separate military encampments, making up approximately 1000 military personnel and their families, undergo randomization to the MMP or FSAT intervention for 3 months, with an additional 3 months' follow-up. In addition, each treatment cluster of military personnel and civilians is also randomly assigned to receive either permethrin- or sham (water)-treated clothing in single-blind fashion. The primary endpoint is risk reduction for malaria infection in geographically distinct military encampments based on their treatment strategy. Monthly malaria screening in both arms is done via microscopy, PCR, and rapid diagnostic testing to compare both the accuracy and cost-effectiveness of diagnostic modalities to detect asymptomatic infection. Universal glucose-6-phosphate dehydrogenase (G6PD) deficiency screening is done at entry, comparing the results from a commercially available rapid diagnostic test, the fluorescence spot test, and quantitative testing for accuracy and cost-effectiveness. The comparative safety of the interventions chosen is also being evaluated. DISCUSSION Despite the apparent urgency, the key operational elements of proposed malaria elimination strategies in Southeast Asian mobile and migrant populations, including the Military, have yet to be rigorously tested in a well-controlled clinical study. Here, we present a protocol for the primary evaluation of two treatment paradigms - monthly malaria prophylaxis and focused screening and treatment - to achieve malaria elimination in a Cambodian military population. We will also assess the feasibility and incremental benefit of outdoor-biting vector intervention - permethrin-treated clothing. In the process, we aim to define the cost-effectiveness of the inputs required for success including a responsive information system, skilled human resource and laboratory infrastructure requirements, and quality management. Despite being a relatively low transmission area, the complexities of multi-drug-resistant malaria and the movement of vulnerable populations require an approach that is not only technically sound, but simple enough to be achievable. TRIAL REGISTRATION ClinicalTrials.gov, ID: NCT02653898 . Registered on 13 January 2016.
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Tyagi RK, Gleeson PJ, Arnold L, Tahar R, Prieur E, Decosterd L, Pérignon JL, Olliaro P, Druilhe P. High-level artemisinin-resistance with quinine co-resistance emerges in P. falciparum malaria under in vivo artesunate pressure. BMC Med 2018; 16:181. [PMID: 30269689 PMCID: PMC6166299 DOI: 10.1186/s12916-018-1156-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/17/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Humanity has become largely dependent on artemisinin derivatives for both the treatment and control of malaria, with few alternatives available. A Plasmodium falciparum phenotype with delayed parasite clearance during artemisinin-based combination therapy has established in Southeast Asia, and is emerging elsewhere. Therefore, we must know how fast, and by how much, artemisinin-resistance can strengthen. METHODS P. falciparum was subjected to discontinuous in vivo artemisinin drug pressure by capitalizing on a novel model that allows for long-lasting, high-parasite loads. Intravenous artesunate was administered, using either single flash-doses or a 2-day regimen, to P. falciparum-infected humanized NOD/SCID IL-2Rγ-/-immunocompromised mice, with progressive dose increments as parasites recovered. The parasite's response to artemisinins and other available anti-malarial compounds was characterized in vivo and in vitro. RESULTS Artemisinin resistance evolved very rapidly up to extreme, near-lethal doses of artesunate (240 mg/kg), an increase of > 3000-fold in the effective in vivo dose, far above resistance levels reported from the field. Artemisinin resistance selection was reproducible, occurring in 80% and 41% of mice treated with flash-dose and 2-day regimens, respectively, and the resistance phenotype was stable. Measuring in vitro sensitivity proved inappropriate as an early marker of resistance, as IC50 remained stable despite in vivo resistance up to 30 mg/kg (ART-S: 10.7 nM (95% CI 10.2-11.2) vs. ART-R30: 11.5 nM (6.6-16.9), F = 0.525, p = 0.47). However, when in vivo resistance strengthened further, IC50 increased 10-fold (ART-R240 100.3 nM (92.9-118.4), F = 304.8, p < 0.0001), reaching a level much higher than ever seen in clinical samples. Artemisinin resistance in this African P. falciparum strain was not associated with mutations in kelch-13, casting doubt over the universality of this genetic marker for resistance screening. Remarkably, despite exclusive exposure to artesunate, full resistance to quinine, the only other drug sufficiently fast-acting to deal with severe malaria, evolved independently in two parasite lines exposed to different artesunate regimens in vivo, and was confirmed in vitro. CONCLUSION P. falciparum has the potential to evolve extreme artemisinin resistance and more complex patterns of multidrug resistance than anticipated. If resistance in the field continues to advance along this trajectory, we will be left with a limited choice of suboptimal treatments for acute malaria, and no satisfactory option for severe malaria.
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Affiliation(s)
- Rajeev K Tyagi
- The Vac4All Initiative, 26 Rue Lecourbe, 75015, Paris, France
- Biomedical Parasitology Unit, Institut Pasteur, Paris, France
- Present Address: Amity Institute of Microbial Technology, Amity University, Noida, Uttar Pradesh, India
| | - Patrick J Gleeson
- The Vac4All Initiative, 26 Rue Lecourbe, 75015, Paris, France
- Biomedical Parasitology Unit, Institut Pasteur, Paris, France
- Present Address: Centre de Recherche sur l'Inflammation, INSERM U1149, Faculté de Médecine, Université Diderot-Site Bichat, 16 rue Henri Huchard, 75018, Paris, France
| | - Ludovic Arnold
- The Vac4All Initiative, 26 Rue Lecourbe, 75015, Paris, France
- Biomedical Parasitology Unit, Institut Pasteur, Paris, France
| | - Rachida Tahar
- Faculté de Pharmacie, Université Paris Descartes, COMUE Sorbonne Paris Cité, Paris, France
- Institut de Recherche pour le Développement, UMR MERIT 216, Paris, France
| | - Eric Prieur
- The Vac4All Initiative, 26 Rue Lecourbe, 75015, Paris, France
- Biomedical Parasitology Unit, Institut Pasteur, Paris, France
| | - Laurent Decosterd
- Division of Clinical Pharmacology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Jean-Louis Pérignon
- The Vac4All Initiative, 26 Rue Lecourbe, 75015, Paris, France
- Biomedical Parasitology Unit, Institut Pasteur, Paris, France
- Present Address: Laboratoire de Biochimie, Hôpital Necker-Enfants Malades, Paris, France
| | - Piero Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Pierre Druilhe
- The Vac4All Initiative, 26 Rue Lecourbe, 75015, Paris, France.
- Biomedical Parasitology Unit, Institut Pasteur, Paris, France.
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Bruneel F, Raffetin A, Corne P, Llitjos JF, Mourvillier B, Argaud L, Wolff M, Laurent V, Jauréguiberry S. Management of severe imported malaria in adults. Med Mal Infect 2018; 50:213-225. [PMID: 30266432 DOI: 10.1016/j.medmal.2018.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 08/30/2018] [Indexed: 11/28/2022]
Abstract
Severe malaria accounts for approximately 10% of all cases of imported malaria in France; cases are mainly due to Plasmodium falciparum, while other Plasmodium species are possible but uncommon (P. vivax, P. knowlesi, P. malariae, and P. ovale). On the basis of WHO criteria for endemic areas, the French criteria defining severe imported malaria in adults have been progressively adapted to the European healthcare level. Management of severe imported malaria is a diagnostic and treatment emergency and must be initially conducted in the intensive care unit. Anti-infective treatment is now based on intravenous artesunate, which must be available in every hospital of the country likely to receive severe imported malaria patients. Intravenous quinine is thus used as a second-line treatment and is restricted to limited indications. Critical care management of organ failure is essential, particularly in patients presenting with very severe malaria. To date, no adjunctive therapy (including exchange transfusion) has demonstrated clear beneficial effects.
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Affiliation(s)
- F Bruneel
- Réanimation médico-chirurgicale, hôpital Mignot, centre hospitalier de Versailles, 177, rue de Versailles, 78150 Le Chesnay, France.
| | - A Raffetin
- Médecine interne, maladies infectieuses et tropicales, CHI Villeneuve-Saint-Georges, 94190 Villeneuve-Saint-Georges, France
| | - P Corne
- Réanimation médicale, CHU de Montpellier, 34000 Montpellier, France
| | - J F Llitjos
- Réanimation médicale, CHU Cochin, 75014 Paris, France
| | - B Mourvillier
- Réanimation médicale et infectieuse, CHU Bichat-Claude-Bernard, 75018 Paris, France
| | - L Argaud
- Réanimation médicale, CHU Edouard-Herriot, 69000 Lyon, France
| | - M Wolff
- Réanimation médicale et infectieuse, CHU Bichat-Claude-Bernard, 75018 Paris, France
| | - V Laurent
- Réanimation médico-chirurgicale, hôpital Mignot, centre hospitalier de Versailles, 177, rue de Versailles, 78150 Le Chesnay, France
| | - S Jauréguiberry
- Maladies infectieuses et tropicales, CHU Pitié-Salpêtrière, 75013 Paris, France
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Molecular assays for antimalarial drug resistance surveillance: A target product profile. PLoS One 2018; 13:e0204347. [PMID: 30235327 PMCID: PMC6147503 DOI: 10.1371/journal.pone.0204347] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 09/05/2018] [Indexed: 11/25/2022] Open
Abstract
Antimalarial drug resistance is a major constraint for malaria control and elimination efforts. Artemisinin-based combination therapy is now the mainstay for malaria treatment. However, delayed parasite clearance following treatment with artemisinin derivatives has now spread in the Greater Mekong Sub region and may emerge or spread to other malaria endemic regions. This spread is of great concern for malaria control programmes, as no alternatives to artemisinin-based combination therapies are expected to be available in the near future. There is a need to strengthen surveillance systems for early detection and response to the antimalarial drug resistance threat. Current surveillance is mainly done through therapeutic efficacy studies; however these studies are complex and both time- and resource-intensive. For multiple common antimalarials, parasite drug resistance has been correlated with specific genetic mutations, and the molecular markers associated with antimalarial drug resistance offer a simple and powerful tool to monitor the emergence and spread of resistant parasites. Different techniques to analyse molecular markers associated with antimalarial drug resistance are available, each with advantages and disadvantages. However, procedures are not adequately harmonized to facilitate comparisons between sites. Here we describe the target product profiles for tests to analyse molecular markers associated with antimalarial drug resistance, discuss how use of current techniques can be standardised, and identify the requirements for an ideal product that would allow malaria endemic countries to provide useful spatial and temporal information on the spread of resistance.
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Ebenebe JC, Ntadom G, Ambe J, Wammanda R, Jiya N, Finomo F, Emechebe G, Mokuolu O, Akano K, Agomo C, Folarin OA, Oguche S, Useh F, Oyibo W, Aderoyeje T, Abdulkadir M, Ezeigwe NM, Happi C, Sowunmi A. Efficacy of Artemisinin-Based Combination Treatments of Uncomplicated Falciparum Malaria in Under-Five-Year-Old Nigerian Children Ten Years Following Adoption as First-Line Antimalarials. Am J Trop Med Hyg 2018; 99:649-664. [PMID: 29943725 PMCID: PMC6169162 DOI: 10.4269/ajtmh.18-0115] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 05/08/2018] [Indexed: 11/07/2022] Open
Abstract
The efficacies of 3-day regimens of artemether-lumefantrine (AL), artesunate-amodiaquine (AA), and dihydroartemisinin-piperaquine (DHP) were evaluated in 910 children < 5 years old with uncomplicated malaria from six geographical areas of Nigeria. Parasite positivity 1 day and Kaplan-Meier estimated risk of persistent parasitemia 3 days after therapy initiation were both significantly higher, and geometric mean parasite reduction ratio 1 day after treatment initiation (PRRD1) was significantly lower in AL-treated children than in AA- and DHP-treated children. No history of fever, temperature > 38°C, enrollment parasitemia > 75,000 μL-1, and PRRD1 < 5,000 independently predicted persistent parasitemia 1 day after treatment initiation. Parasite clearance was significantly faster and risk of reappearance of asexual parasitemia after initial clearance was significantly lower in DHP-treated children. Overall, day 42 polymerase chain reaction-corrected efficacy was 98.3% (95% confidence interval [CI]: 96.1-100) and was similar for all treatments. In a non-compartment model, declines of parasitemias were monoexponential with mean terminal elimination half-life of 1.3 hours and unimodal frequency distribution of half-lives. All treatments were well tolerated. In summary, all three treatments evaluated remain efficacious treatments of uncomplicated malaria in young Nigerian children, but DHP appears more efficacious than AL or AA.
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Affiliation(s)
- Joy C. Ebenebe
- Department of Paediatrics, Nnamdi Azikiwe University, Awka, Nigeria
| | - Godwin Ntadom
- National Malaria Elimination Programme, The Federal Ministry of Health, Abuja, Nigeria
| | - Jose Ambe
- Department of Paediatrics, University of Maiduguri, Maiduguri, Nigeria
| | | | - Nma Jiya
- Department of Paediatrics, Uthman Dan Fodio University, Sokoto, Nigeria
| | - Finomo Finomo
- Department of Paediatrics, Federal Medical Centre, Yenagoa, Nigeria
| | - George Emechebe
- Department of Paediatrics, Imo State University Teaching Hospital, Orlu, Nigeria
| | - Olugbenga Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Kazeem Akano
- Department of Pharmacology and Therapeutics, University of Ibadan, Ibadan, Nigeria
| | - Chimere Agomo
- Department of Medical Laboratory Science, University of Lagos, Lagos, Nigeria
| | - Onikepe A. Folarin
- Department of Biological Sciences and African Centre of Excellence for Genomics of Infectious Diseases (ACEGID), Redeemer University, Ede, Nigeria
| | - Stephen Oguche
- Department of Paediatrics, University of Jos, Jos, Nigeria
| | - Francis Useh
- Department of Medical Laboratory Science, University of Calabar, Calabar, Nigeria
| | - Wellington Oyibo
- Department of Medical Microbiology and Parasitology, University of Lagos, Lagos, Nigeria
| | - Temitope Aderoyeje
- Department of Clinical Pharmacology, University College Hospital, Ibadan, Nigeria
- Institute for Medical Research and Training, University of Ibadan, Ibadan, Nigeria
| | - Mohammed Abdulkadir
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Nnenna M. Ezeigwe
- National Malaria Elimination Programme, The Federal Ministry of Health, Abuja, Nigeria
| | - Christian Happi
- Department of Biological Sciences and African Centre of Excellence for Genomics of Infectious Diseases (ACEGID), Redeemer University, Ede, Nigeria
| | - Akintunde Sowunmi
- Department of Pharmacology and Therapeutics, University of Ibadan, Ibadan, Nigeria
- Department of Clinical Pharmacology, University College Hospital, Ibadan, Nigeria
- Institute for Medical Research and Training, University of Ibadan, Ibadan, Nigeria
| | - for the Antimalarial Therapeutic Efficacy Monitoring Group, National Malaria Elimination Programme, The Federal Ministry of Health, Abuja, Nigeria
- Department of Paediatrics, Nnamdi Azikiwe University, Awka, Nigeria
- National Malaria Elimination Programme, The Federal Ministry of Health, Abuja, Nigeria
- Department of Paediatrics, University of Maiduguri, Maiduguri, Nigeria
- Department of Paediatrics, Ahmadu Bello University, Zaria, Nigeria
- Department of Paediatrics, Uthman Dan Fodio University, Sokoto, Nigeria
- Department of Paediatrics, Federal Medical Centre, Yenagoa, Nigeria
- Department of Paediatrics, Imo State University Teaching Hospital, Orlu, Nigeria
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
- Department of Pharmacology and Therapeutics, University of Ibadan, Ibadan, Nigeria
- Department of Medical Laboratory Science, University of Lagos, Lagos, Nigeria
- Department of Biological Sciences and African Centre of Excellence for Genomics of Infectious Diseases (ACEGID), Redeemer University, Ede, Nigeria
- Department of Paediatrics, University of Jos, Jos, Nigeria
- Department of Medical Laboratory Science, University of Calabar, Calabar, Nigeria
- Department of Medical Microbiology and Parasitology, University of Lagos, Lagos, Nigeria
- Department of Clinical Pharmacology, University College Hospital, Ibadan, Nigeria
- Institute for Medical Research and Training, University of Ibadan, Ibadan, Nigeria
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Popovici J, Vantaux A, Primault L, Samreth R, Piv EP, Bin S, Kim S, Lek D, Serre D, Menard D. Therapeutic and Transmission-Blocking
Efficacy of Dihydroartemisinin/Piperaquine and Chloroquine against Plasmodium vivax Malaria, Cambodia. Emerg Infect Dis 2018; 24:1516-1519. [PMID: 29798745 PMCID: PMC6056113 DOI: 10.3201/eid2408.170768] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We assessed the efficacy of standard 3-day courses of chloroquine and dihydroartemisinin/piperaquine against Plasmodium vivax malaria. Compared with chloroquine, dihydroartemisinin/piperaquine was faster in clearing asexual P. vivax parasites and blocking human-to-mosquito transmission. This drug combination was also more effective in preventing potential recurrences for >2 months.
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Gupta H, Macete E, Bulo H, Salvador C, Warsame M, Carvalho E, Ménard D, Ringwald P, Bassat Q, Enosse S, Mayor A. Drug-Resistant Polymorphisms and Copy Numbers in Plasmodium falciparum, Mozambique, 2015. Emerg Infect Dis 2018; 24:40-48. [PMID: 29260689 PMCID: PMC5749434 DOI: 10.3201/eid2401.170864] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
One of the fundamental steps toward malaria control is the use of antimalarial drugs. The success of antimalarial treatment can be affected by the presence of drug-resistant populations of Plasmodium falciparum. To assess resistance, we used molecular methods to examine 351 P. falciparum isolates collected from 4 sentinel sites in Mozambique for K13, pfmdr1, pfcrt, and pfdhps polymorphisms and for plasmepsin2 (pfpm2) and pfmdr1 copy numbers. We found multiple copies of pfpm2 in 1.1% of isolates. All isolates carried K13 wild-type alleles (3D7-like), except 4 novel polymorphisms (Leu619Leu, Phe656Ile, Val666Val, Gly690Gly). Prevalence of isolates with pfcrt mutant (K76T) allele was low (2.3%). Prevalence of isolates with pfdhps mutant alleles (A437G and K540E) was >80%, indicating persistence of sulfadoxine/pyrimethamine resistance; however, markers of artemisinin were absent, and markers of piperaquine resistance were low. Piperaquine resistance isolates may spread in Mozambique as dihydroartemisinin/piperaquine drug pressure increases.
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