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Oyegoke OO, Akoniyon OP, Maharaj L, Adewumi TS, Malgwi SA, Aderoju SA, Fatoba AJ, Adeleke MA, Maharaj R, Okpeku M. Molecular detection of sub-microscopic infections and Plasmodium falciparum histidine-rich protein-2 and 3 gene deletions in pre-elimination settings of South Africa. Sci Rep 2024; 14:16024. [PMID: 38992085 PMCID: PMC11239831 DOI: 10.1038/s41598-024-60007-8] [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: 08/17/2023] [Accepted: 04/17/2024] [Indexed: 07/13/2024] Open
Abstract
South Africa's efforts toward eliminating malaria have positioned the country in the pre-elimination stage. Imported and sub-microscopic cases still contribute to the persistence of malaria in regions of low transmission as identified in this study where diagnostics is built largely on the use of Rapid Diagnostic Test (RDT). However, the presence of Pfhrp2/3 gene deletion is known to interfere with the accuracy of diagnosis with the use of RDT. Malaria elimination and detection of Pfhrp2/3 gene deletion in the pre-elimination setting requires accurate molecular surveillance. With the core objective of this study being the determination of the presence sub-microscopic malaria cases and deleted Pfhrp2/3 gene markers, a total of 354 samples were collected from five districts of KwaZulu Natal, South Africa. These samples were prepared for molecular analysis using primers and PCR conditions specific for amplification of 18S rRNA and msp-1gene. Positive amplicons were analysed for the presence of Pfhrp2/3 and flanking genes, along with Sanger sequencing and phylogenetic studies. Out of 354 samples collected 339 were tested negative with PfHRP2 based RDTs. Of these Pfhrp2 and Pfhrp3 gene deletions were confirmed in 94.7% (18/19) and 100% (19/19) respectively. High migration rate (75%) among the study participants was noted and phylogenetic analysis of sequenced isolates showed close evolutionary relatedness with India, United Kingdom, Iran, and Myanmar and China isolates. Molecular-based test is recommended as an essential surveillance tool for malaria management programs as the target focuses on elimination.
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Affiliation(s)
- Olukunle O Oyegoke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Olusegun P Akoniyon
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Leah Maharaj
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Taiye S Adewumi
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66046, USA
| | - Samson A Malgwi
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Samuel A Aderoju
- Department of Mathematics and Statistics, Kwara State University, Ilorin, Nigeria
| | - Abiodun J Fatoba
- Department of Genetics, Genomics and Bioinformatics, University of Tennessee Health Science Centre, Memphis, TN, 38016, USA
| | - Matthew A Adeleke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Rajendra Maharaj
- Malaria Research Unit, South African Medical Research Council, Durban, South Africa
| | - Moses Okpeku
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa.
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Mekonen B, Dugassa S, Feleke SM, Dufera B, Gidisa B, Adamu A, Mandefro A, Tasew G, Golassa L. Widespread pfhrp2/3 deletions and HRP2-based false-negative results in southern Ethiopia. Malar J 2024; 23:108. [PMID: 38632640 PMCID: PMC11025231 DOI: 10.1186/s12936-024-04904-3] [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: 10/02/2023] [Accepted: 03/08/2024] [Indexed: 04/19/2024] Open
Abstract
BACKGROUND Rapid diagnostic tests (RDTs) play a significant role in expanding case management in peripheral healthcare systems. Histidine-rich protein-2 (HRP2) antigen detection RDTs are predominantly used to diagnose Plasmodium falciparum infection. However, the evolution and spread of P. falciparum parasite strains with deleted hrp2/3 genes, causing false-negative results, have been reported. This study assessed the diagnostic performance of HRP2-detecting RDTs for P. falciparum cases and the prevalence of pfhrp2/3 deletions among symptomatic patients seeking malaria diagnosis at selected health facilities in southern Ethiopia. METHODS A multi-health facilities-based cross-sectional study was conducted on self-presenting febrile patients seeking treatment in southern Ethiopia from July to September 2022. A purposive sampling strategy was used to enroll patients with microscopically confirmed P. falciparum infections. A capillary blood sample was obtained to prepare a blood film for microscopy and a RDT using the SD Bioline™ Malaria Pf/Pv Test. Dried blood spot samples were collected for further molecular analysis. DNA was extracted using gene aid kits and amplification was performed using nested PCR assay. Exon 2 of hrp2 and hrp3, which are the main protein-coding regions, was used to confirm its deletion. The diagnostic performance of RDT was evaluated using PCR as the gold standard test for P. falciparum infections. RESULTS Of 279 P. falciparum PCR-confirmed samples, 249 (89.2%) had successful msp-2 amplification, which was then genotyped for hrp2/3 gene deletions. The study revealed that pfhrp2/3 deletions were common in all health centres, and it was estimated that 144 patients (57.8%) across all health facilities had pfhrp2/3 deletions, leading to false-negative PfHRP2 RDT results. Deletions spanning exon 2 of hrp2, exon 2 of hrp3, and double deletions (hrp2/3) accounted for 68 (27.3%), 76 (30.5%), and 33 (13.2%) of cases, respectively. The study findings revealed the prevalence of P. falciparum parasites lacking a single pfhrp2-/3-gene and that both genes varied across the study sites. This study also showed that the sensitivity of the SD Bioline PfHRP2-RDT test was 76.5% when PCR was used as the reference test. CONCLUSION This study confirmed the existence of widespread pfhrp2/3- gene deletions, and their magnitude exceeded the WHO-recommended threshold (> 5%). False-negative RDT results resulting from deletions in Pfhrp2/3- affect a country's attempts at malaria control and elimination. Therefore, the adoption of non-HRP2-based RDTs as an alternative measure is required to avoid the consequences associated with the continued use of HRP-2-based RDTs, in the study area in particular and in Ethiopia in general.
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Affiliation(s)
- Bacha Mekonen
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
- Malaria and NTDs Research Team, Bacterial, Parasitic, and Zoonotic Diseases Research Directorate, Ethiopian Public Health Institute, Addis Ababa, Ethiopia.
| | - Sisay Dugassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Sindew Mekasha Feleke
- Malaria and NTDs Research Team, Bacterial, Parasitic, and Zoonotic Diseases Research Directorate, Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Boja Dufera
- Malaria and NTDs Research Team, Bacterial, Parasitic, and Zoonotic Diseases Research Directorate, Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Bedasa Gidisa
- Malaria and NTDs Research Team, Armeur Hansen Research Institute, Addis Ababa, Ethiopia
| | - Aderaw Adamu
- Department of Medical Laboratory Science, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia
| | - Aynalem Mandefro
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Geremew Tasew
- Malaria and NTDs Research Team, Bacterial, Parasitic, and Zoonotic Diseases Research Directorate, Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
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Mwanga EP, Siria DJ, Mshani IH, Mwinyi SH, Abbasi S, Jimenez MG, Wynne K, Baldini F, Babayan SA, Okumu FO. Rapid classification of epidemiologically relevant age categories of the malaria vector, Anopheles funestus. Parasit Vectors 2024; 17:143. [PMID: 38500231 PMCID: PMC10949582 DOI: 10.1186/s13071-024-06209-5] [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: 01/04/2024] [Accepted: 02/21/2024] [Indexed: 03/20/2024] Open
Abstract
BACKGROUND Accurately determining the age and survival probabilities of adult mosquitoes is crucial for understanding parasite transmission, evaluating the effectiveness of control interventions and assessing disease risk in communities. This study was aimed at demonstrating the rapid identification of epidemiologically relevant age categories of Anopheles funestus, a major Afro-tropical malaria vector, through the innovative combination of infrared spectroscopy and machine learning, instead of the cumbersome practice of dissecting mosquito ovaries to estimate age based on parity status. METHODS Anopheles funestus larvae were collected in rural south-eastern Tanzania and reared in an insectary. Emerging adult females were sorted by age (1-16 days old) and preserved using silica gel. Polymerase chain reaction (PCR) confirmation was conducted using DNA extracted from mosquito legs to verify the presence of An. funestus and to eliminate undesired mosquitoes. Mid-infrared spectra were obtained by scanning the heads and thoraces of the mosquitoes using an attenuated total reflection-Fourier transform infrared (ATR-FT-IR) spectrometer. The spectra (N = 2084) were divided into two epidemiologically relevant age groups: 1-9 days (young, non-infectious) and 10-16 days (old, potentially infectious). The dimensionality of the spectra was reduced using principal component analysis, and then a set of machine learning and multi-layer perceptron (MLP) models were trained using the spectra to predict the mosquito age categories. RESULTS The best-performing model, XGBoost, achieved overall accuracy of 87%, with classification accuracy of 89% for young and 84% for old An. funestus. When the most important spectral features influencing the model performance were selected to train a new model, the overall accuracy increased slightly to 89%. The MLP model, utilizing the significant spectral features, achieved higher classification accuracy of 95% and 94% for the young and old An. funestus, respectively. After dimensionality reduction, the MLP achieved 93% accuracy for both age categories. CONCLUSIONS This study shows how machine learning can quickly classify epidemiologically relevant age groups of An. funestus based on their mid-infrared spectra. Having been previously applied to An. gambiae, An. arabiensis and An. coluzzii, this demonstration on An. funestus underscores the potential of this low-cost, reagent-free technique for widespread use on all the major Afro-tropical malaria vectors. Future research should demonstrate how such machine-derived age classifications in field-collected mosquitoes correlate with malaria in human populations.
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Affiliation(s)
- Emmanuel P Mwanga
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P.O. Box 53, Morogoro, Tanzania.
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK.
| | - Doreen J Siria
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P.O. Box 53, Morogoro, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Issa H Mshani
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P.O. Box 53, Morogoro, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Sophia H Mwinyi
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P.O. Box 53, Morogoro, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Said Abbasi
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P.O. Box 53, Morogoro, Tanzania
| | - Mario Gonzalez Jimenez
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
- School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Klaas Wynne
- School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Francesco Baldini
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Simon A Babayan
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Fredros O Okumu
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P.O. Box 53, Morogoro, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G12 8QQ, UK
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- School of Life Science and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
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Mukadi-Kaningu P, Muele FK, Tshimanga N, Unandu J, Mbamba BMB, Sompwe EM. Unravelling the quality of malaria microscopy across Kinshasa, DR Congo. MALARIAWORLD JOURNAL 2024; 15:2. [PMID: 38505576 PMCID: PMC10949414 DOI: 10.5281/zenodo.10630995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Introduction In the current study we assessed clinical laboratories' staff ability across the city of Kinshasa with particular focus on their practices and performance regarding malaria microscopy. Materials and Methods This was a non-random cross-sectional study included clinical laboratories in Kinshasa and focused on cross-checking of blood slides, a questionnaire and checklist according to standardised analytic malaria microscopy procedures. Regarding the cross-checking of slides, participant responses were considered 'corrects' in cases of complete congruence with the reference; 'acceptable' for malaria-positive slides but no identification of Plasmodium species, stage of development, parasite density and/or reported as P. falciparum instead of 'P. non falciparum'; and 'incorrect' if 'false positive' and 'false negative' cases. Results Eighty-eight among the 90 targeted clinical laboratories (participation 97.8%) took part in the investigation from February to July 2019. The ability assessment revealed that individuals qualified to perform thick blood films (TBF) according to the national malaria control program (NMCP) procedures ranged from 48.6% to 100.0%. Overall cross-checking performance of 167 eligible routine slides was relatively low: 37.7%; 25.8% and 36.5% of correct, acceptable and incorrect responses, respectively. The first routine slide was correctly and acceptably scored respectively by 35.3% and 28.2% of participating laboratories (n = 85); and the second, by 40.2% and 23.2% respectively (n = 82). The sensitivity and specificity were found to be 79.4% and 53.8%, respectively. However, the relative high scores reported in relation with the ability needed to perform TBF based on NMCP standards contrasted with the poor performance from cross-checking slides. Consecutively, only one-third of the 88 participating laboratories reached a score > 60% in agreement with NMCP procedures and had acceptable responses to cross-checked slides. Conclusions The study was conducted as part of the activities relating to "Ensuring early diagnosis and prompt malaria treatment" component of the national malaria control strategy with NMCP support. More laboratories must implement clear and standardised malaria microscopy procedures, and need to include more rigorous quality control.
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Affiliation(s)
- Pierre Mukadi-Kaningu
- Université Pédagogique Nationale, B.P. 8815, Kinshasa 1, DR Congo
- Institut National de Recherche Biomédicale, Kinshasa, DR Congo
| | | | - Nestor Tshimanga
- Université Pédagogique Nationale, B.P. 8815, Kinshasa 1, DR Congo
| | - Joel Unandu
- Université Pédagogique Nationale, B.P. 8815, Kinshasa 1, DR Congo
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Levine ZC, Sene A, Mkandawire W, Deme AB, Ndiaye T, Sy M, Gaye A, Diedhiou Y, Mbaye AM, Ndiaye IM, Gomis J, Ndiop M, Sene D, Faye Paye M, MacInnis BL, Schaffner SF, Park DJ, Badiane AS, Colubri A, Ndiaye M, Sy N, Sabeti PC, Ndiaye D, Siddle KJ. Investigating the etiologies of non-malarial febrile illness in Senegal using metagenomic sequencing. Nat Commun 2024; 15:747. [PMID: 38272885 PMCID: PMC10810818 DOI: 10.1038/s41467-024-44800-7] [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: 08/22/2023] [Accepted: 01/04/2024] [Indexed: 01/27/2024] Open
Abstract
The worldwide decline in malaria incidence is revealing the extensive burden of non-malarial febrile illness (NMFI), which remains poorly understood and difficult to diagnose. To characterize NMFI in Senegal, we collected venous blood and clinical metadata in a cross-sectional study of febrile patients and healthy controls in a low malaria burden area. Using 16S and untargeted sequencing, we detected viral, bacterial, or eukaryotic pathogens in 23% (38/163) of NMFI cases. Bacteria were the most common, with relapsing fever Borrelia and spotted fever Rickettsia found in 15.5% and 3.8% of cases, respectively. Four viral pathogens were found in a total of 7 febrile cases (3.5%). Sequencing also detected undiagnosed Plasmodium, including one putative P. ovale infection. We developed a logistic regression model that can distinguish Borrelia from NMFIs with similar presentation based on symptoms and vital signs (F1 score: 0.823). These results highlight the challenge and importance of improved diagnostics, especially for Borrelia, to support diagnosis and surveillance.
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Affiliation(s)
- Zoë C Levine
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Harvard Graduate Program in Biological and Biomedical Science, Boston, MA, USA
- Harvard/MIT MD-PhD Program, Boston, MA, USA
| | - Aita Sene
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Winnie Mkandawire
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- University of Massachusetts Medical School, Worcester, MA, USA
| | - Awa B Deme
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Tolla Ndiaye
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Mouhamad Sy
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Amy Gaye
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Younouss Diedhiou
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Amadou M Mbaye
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Ibrahima M Ndiaye
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Jules Gomis
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Médoune Ndiop
- Programme National de lutte contre le Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | - Doudou Sene
- Programme National de lutte contre le Paludisme, Ministère de la Santé, Dakar Fann, Senegal
| | | | - Bronwyn L MacInnis
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Stephen F Schaffner
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Daniel J Park
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Aida S Badiane
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Andres Colubri
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- University of Massachusetts Medical School, Worcester, MA, USA
| | - Mouhamadou Ndiaye
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal
| | - Ngayo Sy
- Service de Lutte Anti Parasitaire, Thies, Senegal
| | - Pardis C Sabeti
- Broad Institute of Harvard and MIT, Cambridge, MA, USA.
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA.
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| | - Daouda Ndiaye
- Department of Parasitology, Cheikh Anta Diop University Dakar, Dakar, Senegal.
- Centre International de Recherche et de Formation en Génomique Appliquée et de la Surveillance Sanitaire, Dakar, Senegal.
| | - Katherine J Siddle
- Broad Institute of Harvard and MIT, Cambridge, MA, USA.
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, USA.
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Agaba BB, Smith D, Travis J, Pasay C, Nabatanzi M, Arinaitwe E, Ssewanyana I, Nabadda S, Cunningham J, Kamya MR, Cheng Q. Limited threat of Plasmodium falciparum pfhrp2 and pfhrp3 gene deletion to the utility of HRP2-based malaria RDTs in Northern Uganda. Malar J 2024; 23:3. [PMID: 38167003 PMCID: PMC10759665 DOI: 10.1186/s12936-023-04830-w] [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: 10/02/2023] [Accepted: 12/21/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Rapid diagnostic tests (RDTs) that detect Plasmodium falciparum histidine-rich protein-2 (PfHRP2) are exclusively deployed in Uganda, but deletion of the pfhrp2/3 target gene threatens their usefulness as malaria diagnosis and surveillance tools. METHODS A cross-sectional survey was conducted at 40 sites across four regions of Uganda in Acholi, Lango, W. Nile and Karamoja from March 2021 to June 2023. Symptomatic malaria suspected patients were recruited and screened with both HRP2 and pan lactate dehydrogenase (pLDH) detecting RDTs. Dried blood spots (DBS) were collected from all patients and a random subset were used for genomic analysis to confirm parasite species and pfhrp2 and pfhrp3 gene status. Plasmodium species was determined using a conventional multiplex PCR while pfhrp2 and pfhrp3 gene deletions were determined using a real-time multiplex qPCR. Expression of the HRP2 protein antigen in a subset of samples was further assessed using a ELISA. RESULTS Out of 2435 symptomatic patients tested for malaria, 1504 (61.8%) were positive on pLDH RDT. Overall, qPCR confirmed single pfhrp2 gene deletion in 1 out of 416 (0.2%) randomly selected samples that were confirmed of P. falciparum mono-infections. CONCLUSION These findings show limited threat of pfhrp2/3 gene deletions in the survey areas suggesting that HRP2 RDTs are still useful diagnostic tools for surveillance and diagnosis of P. falciparum malaria infections in symptomatic patients in this setting. Periodic genomic surveillance is warranted to monitor the frequency and trend of gene deletions and its effect on RDTs.
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Affiliation(s)
- Bosco B Agaba
- Faculty of Medicine, Department of Medical Laboratory Sciences, Mbarara University of Science and Technology, Mbarara, Uganda.
- National Malaria Control Division, Kampala, Uganda.
- London School of Hygiene and Tropical Medicine, London, UK.
- Infectious Diseases Research Collaboration, Kampala, Uganda.
| | - David Smith
- QIMR Berghofer Medical Research Institute, Kelvin Grove, QLD, Australia
- Australian Defence Force Malaria and Infectious Disease Institute, Kelvin Grove, Australia
| | - Jye Travis
- QIMR Berghofer Medical Research Institute, Kelvin Grove, QLD, Australia
- Australian Defence Force Malaria and Infectious Disease Institute, Kelvin Grove, Australia
| | - Cielo Pasay
- QIMR Berghofer Medical Research Institute, Kelvin Grove, QLD, Australia
| | | | | | - Isaac Ssewanyana
- Infectious Diseases Research Collaboration, Kampala, Uganda
- National Health Laboratory Services/Central Public Health Laboratories, Kelvin Grove, Uganda
| | - Susan Nabadda
- National Health Laboratory Services/Central Public Health Laboratories, Kelvin Grove, Uganda
| | - Jane Cunningham
- Global Malaria Programme, World Health Organization, Geneva, Switzerland
| | - Moses R Kamya
- Faculty of Medicine, Department of Medical Laboratory Sciences, Mbarara University of Science and Technology, Mbarara, Uganda
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Qin Cheng
- QIMR Berghofer Medical Research Institute, Kelvin Grove, QLD, Australia
- Australian Defence Force Malaria and Infectious Disease Institute, Kelvin Grove, Australia
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Tarama CW, Soré H, Siribié M, Débé S, Kinda R, Nonkani WG, Tiendrebeogo F, Bantango W, Yira K, Hien EY, Guelbéogo MW, Traoré Y, Ménard D, Gansané A. Assessing the histidine-rich protein 2/3 gene deletion in Plasmodium falciparum isolates from Burkina Faso. Malar J 2023; 22:363. [PMID: 38017455 PMCID: PMC10685617 DOI: 10.1186/s12936-023-04796-9] [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: 07/06/2023] [Accepted: 11/17/2023] [Indexed: 11/30/2023] Open
Abstract
BACKGROUND Dual hrp2/hrp3 genes deletions in P. falciparum isolates are increasingly reported in malaria-endemic countries and can produce false negative RDT results leading to inadequate case management. Data on the frequency of hrp2/hrp3 deleted parasites are rarely available and it has become necessary to investigate the issue in Burkina Faso. METHODS Plasmodium falciparum-positive dried blood spots were collected during a cross-sectional household survey of the malaria asymptomatic children from Orodara, Gaoua, and Banfora. Amplicons from the target regions (exon 2 of hrp2 and hrp3 genes) were generated using multiplexed nested PCR and sequenced according to Illumina's MiSeq protocol. RESULTS A total of 251 microscopically positive parasite isolates were sequenced to detect hrp2 and hrp3 gene deletions. The proportion of RDTs negative cases among microscopy positive slides was 12.7% (32/251). The highest prevalence of negative RDTs was found in Orodara 14.3% (5/35), followed by Gaoua 13.1%(24/183), and Banfora 9.1% (3/33). The study found that 95.6% of the parasite isolates were wild type hrp2/ hrp3 while 4.4% (11/251) had a single hrp2 deletion. Of the 11 hrp2 deletion samples, 2 samples were RDT negative (mean parasitaemia was 83 parasites/ μL) while 9 samples were RDT positive with a mean parasitaemia of 520 parasites /μL (CI95%: 192-1239). The highest frequency of hrp2 deletion 4/35 (11.4%) was found in Orodara, while it was similar in the other two sites (< 3.5%). No single deletion of the hrp3 or dual deletion hrp2/3 gene was detected in this study. CONCLUSION These results demonstrate that P. falciparum isolates lacking hrp2 genes are present in 4.4% of samples obtained from the asymptomatic children population in three sites in Burkina Faso. These parasites are circulating and causing malaria, but they are also still detectable by HRP2-based RTDs due to the presence of the intact pfhrp3 gene.
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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
| | - 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
| | | | | | - Yves Traoré
- Université Joseph KI-ZERBO, Ouagadougou, Burkina Faso
| | - Didier Ménard
- Institut Pasteur, Université Paris Cité, Malaria Genetic and Resistance Unit, INSERM U1201, 75015, Paris, France
- Institut Pasteur, Université Paris Cité, Malaria Parasite Biology and Vaccines, F-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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8
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Lupaka M, Degefa T, Eba K, Zeynudin A, Yewhalaw D. Diagnostic performance of ultrasensitive rapid diagnostic test for the detection of Plasmodium falciparum infections in asymptomatic individuals in Kisangani, Northeast Democratic Republic of Congo. Malar J 2023; 22:354. [PMID: 37981691 PMCID: PMC10658930 DOI: 10.1186/s12936-023-04790-1] [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: 07/09/2023] [Accepted: 11/13/2023] [Indexed: 11/21/2023] Open
Abstract
BACKGROUND Ultrasensitive rapid diagnostic test (usRDT) was recently developed to improve the detection of low-density Plasmodium falciparum infections. However, its diagnostic performance has not been evaluated in the Democratic Republic of Congo (DRC). This study aims to determine the performance of the usRDT in malaria diagnosis in asymptomatic individuals under field condition in Kisangani, Northeast of DRC. METHODS A community-based cross-sectional study was carried out from June to August 2022 on 312 asymptomatic individuals residing in the city of Kisangani. Capillary blood samples were collected by finger prick for microscopic examination of thick and thin blood film, RDTs, and nested polymerase chain reaction (PCR). Alere™ Malaria Ag P.f usRDT and conventional RDT (cRDT/SD Bioline Malaria Ag P.f) kits were used for the detection of Plasmodium histidine rich protein 2 (HRP2) antigen as a proxy for the presence of P. falciparum. The diagnostic performance of the usRDT was compared with cRDT, microscopy and PCR. RESULTS The prevalence of asymptomatic P. falciparum malaria was 40.4%, 42.0%, 47.1% and 54.2% by cRDT, microscopy, usRDT and PCR, respectively. By using PCR as a reference, usRDT had sensitivity and specificity of 87.0% (95% CI 81.4-91.7) and 100.0% (95% CI 97.5-100.0), respectively, whereas the cRDT had sensitivity and specificity of 74.6% (95% CI 67.3-80.9) and 100% (95% CI 97.1-100.0), respectively. By using microscopy as a reference, usRDT had sensitivity and specificity of 96.9% (95% CI 92.4-99.2) and 89.0% (95% CI 83.5-93.1), respectively, while the cRDT had sensitivity and specificity of 96.2% (95% CI 92.3-98.7) and 100% (95% CI 97.9-100.0), respectively. CONCLUSION The usRDT showed better diagnostic performance with higher sensitivity than the cRDT which is currently in use as point-of-care test. Further research is necessary to assess the access and cost-effectiveness of the usRDTs to use for malaria surveillance.
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Affiliation(s)
- Mbumba Lupaka
- Faculty of Medicine and Pharmacy, University of Kisangani, Kisangani, Democratic Republic of the Congo
- School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Teshome Degefa
- School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia.
| | - Kasahun Eba
- Department of Environmental Health Sciences and Technology, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Ahmed Zeynudin
- School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
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9
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Msugupakulya BJ, Urio NH, Jumanne M, Ngowo HS, Selvaraj P, Okumu FO, Wilson AL. Changes in contributions of different Anopheles vector species to malaria transmission in east and southern Africa from 2000 to 2022. Parasit Vectors 2023; 16:408. [PMID: 37936155 PMCID: PMC10631025 DOI: 10.1186/s13071-023-06019-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/18/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Malaria transmission in Africa is facilitated by multiple species of Anopheles mosquitoes. These vectors have different behaviors and vectorial capacities and are affected differently by vector control interventions, such as insecticide-treated nets and indoor residual spraying. This review aimed to assess changes in the contribution of different vector species to malaria transmission in east and southern Africa over 20 years of widespread insecticide-based vector control. METHODS We searched PubMed, Global Health, and Web of Science online databases for articles published between January 2000 and April 2023 that provided species-specific sporozoite rates for different malaria vectors in east and southern Africa. We extracted data on study characteristics, biting rates, sporozoite infection proportions, and entomological inoculation rates (EIR). Using EIR data, the proportional contribution of each species to malaria transmission was estimated. RESULTS Studies conducted between 2000 and 2010 identified the Anopheles gambiae complex as the primary malaria vector, while studies conducted from 2011 to 2021 indicated the dominance of Anopheles funestus. From 2000 to 2010, in 57% of sites, An. gambiae demonstrated higher parasite infection prevalence than other Anopheles species. Anopheles gambiae also accounted for over 50% of EIR in 76% of the study sites. Conversely, from 2011 to 2021, An. funestus dominated with higher infection rates than other Anopheles in 58% of sites and a majority EIR contribution in 63% of sites. This trend coincided with a decline in overall EIR and the proportion of sporozoite-infected An. gambiae. The main vectors in the An. gambiae complex in the region were Anopheles arabiensis and An. gambiae sensu stricto (s.s.), while the important member of the An. funestus group was An. funestus s.s. CONCLUSION The contribution of different vector species in malaria transmission has changed over the past 20 years. As the role of An. gambiae has declined, An. funestus now appears to be dominant in most settings in east and southern Africa. Other secondary vector species may play minor roles in specific localities. To improve malaria control in the region, vector control should be optimized to match these entomological trends, considering the different ecologies and behaviors of the dominant vector species.
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Affiliation(s)
- Betwel J Msugupakulya
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, PO Box 53, Ifakara, Tanzania.
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Naomi H Urio
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, PO Box 53, Ifakara, Tanzania
- School of Life Science and Bioengineering, The Nelson Mandela African Institution of Sciences & Technology, Arusha, Tanzania
| | - Mohammed Jumanne
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, PO Box 53, Ifakara, Tanzania
| | - Halfan S Ngowo
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, PO Box 53, Ifakara, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, UK
| | - Prashanth Selvaraj
- Institute for Disease Modeling, Bill and Melinda Gates Foundation, Seattle, USA
| | - Fredros O Okumu
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, PO Box 53, Ifakara, Tanzania.
- School of Life Science and Bioengineering, The Nelson Mandela African Institution of Sciences & Technology, Arusha, Tanzania.
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, UK.
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Park Town, Johannesburg, Republic of South Africa.
| | - Anne L Wilson
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
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10
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Mayor A, Ishengoma DS, Proctor JL, Verity R. Sampling for malaria molecular surveillance. Trends Parasitol 2023; 39:954-968. [PMID: 37730525 PMCID: PMC10580323 DOI: 10.1016/j.pt.2023.08.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/22/2023] [Accepted: 08/23/2023] [Indexed: 09/22/2023]
Abstract
Strategic use of Plasmodium falciparum genetic variation has great potential to inform public health actions for malaria control and elimination. Malaria molecular surveillance (MMS) begins with a strategy to identify and collect parasite samples, guided by public-health priorities. In this review we discuss sampling design practices for MMS and point out epidemiological, biological, and statistical factors that need to be considered. We present examples for different use cases, including detecting emergence and spread of rare variants, establishing transmission sources and inferring changes in malaria transmission intensity. This review will potentially guide the collection of samples and data, serve as a starting point for further methodological innovation, and enhance utilization of MMS to support malaria elimination.
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Affiliation(s)
- Alfredo Mayor
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique; Department of Physiologic Sciences, Faculty of Medicine, Universidade Eduardo Mondlane, Maputo, Mozambique.
| | - Deus S Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania; Faculty of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia; Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Joshua L Proctor
- Institute for Disease Modeling in Global Health, Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Robert Verity
- MRC Centre for Global Infectious Disease Analysis, Imperial College, London, UK
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11
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Bansal V, Munjal J, Lakhanpal S, Gupta V, Garg A, Munjal RS, Jain R. Epidemiological shifts: the emergence of malaria in America. Proc AMIA Symp 2023; 36:745-750. [PMID: 37829240 PMCID: PMC10566419 DOI: 10.1080/08998280.2023.2255514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 09/01/2023] [Indexed: 10/14/2023] Open
Abstract
Plasmodium is a genus of parasites that comprises different species. The species falciparum, vivax, malariae, ovale, and knowlesi are known to cause a vector-borne illness called malaria, and among these, falciparum is known to cause major complications. The vector, the Anopheles mosquito, is commonly found in warmer regions close to the equator, and hence transmission and numbers of cases tend to be higher in Sub-Saharan Africa, South Asia, and Central America. The number of cases of malaria in the United States has remained stable over the years with low transmission rates, and the disease is mostly seen in the population with a recent travel history to endemic regions. The main reason behind this besides the weather conditions is that economically developed countries have eliminated mosquitos. However, there have been reports of locally reported cases with Plasmodium vivax in areas such as Florida and Texas in patients with no known travel history. This paper aims to familiarize US physicians with the pathophysiology, clinical features, and diagnostic modalities of malaria, as well as available treatment options.
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Affiliation(s)
- Vasu Bansal
- Internal Medicine, Dayanand Medical College and Hospital, Ludhiana, Punjab, India
| | - Jaskaran Munjal
- Internal Medicine, Shri Ram Murti Smarak Institute of Medical Sciences, Bareilly, Uttar Pradesh, India
| | | | - Vasu Gupta
- Department of Internal Medicine, Cleveland Clinic Akron General, Akron, OhioUSA
| | - Ashwani Garg
- Penn State Milton S. Hershey Medical Center, Hershey, PennsylvaniaUSA
| | | | - Rohit Jain
- Penn State Milton S. Hershey Medical Center, Hershey, PennsylvaniaUSA
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12
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Levine ZC, Sene A, Mkandawire W, Deme AB, Ndiaye T, Sy M, Gaye A, Diedhiou Y, Mbaye AM, Ndiaye I, Gomis J, Ndiop M, Sene D, Paye MF, MacInnis B, Schaffner SF, Park DJ, Badiane AS, Colubri A, Ndiaye M, Sy N, Sabeti PC, Ndiaye D, Siddle KJ. Improving diagnosis of non-malarial fevers in Senegal: Borrelia and the contribution of tick-borne bacteria. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.08.24.23294564. [PMID: 37662407 PMCID: PMC10473814 DOI: 10.1101/2023.08.24.23294564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
The worldwide decline in malaria incidence is revealing the extensive burden of non-malarial febrile illness (NMFI), which remains poorly understood and difficult to diagnose. To characterize NMFI in Senegal, we collected venous blood and clinical metadata from febrile patients and healthy controls in a low malaria burden area. Using 16S and unbiased sequencing, we detected viral, bacterial, or eukaryotic pathogens in 29% of NMFI cases. Bacteria were the most common, with relapsing fever Borrelia and spotted fever Rickettsia found in 15% and 3.7% of cases, respectively. Four viral pathogens were found in a total of 7 febrile cases (3.5%). Sequencing also detected undiagnosed Plasmodium, including one putative P. ovale infection. We developed a logistic regression model to distinguish Borrelia from NMFIs with similar presentation based on symptoms and vital signs. These results highlight the challenge and importance of improved diagnostics, especially for Borrelia, to support diagnosis and surveillance.
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Affiliation(s)
- Zoë C Levine
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Harvard Graduate Program in Biological and Biomedical Science, Boston, MA, USA
- Harvard/MIT MD-PhD Program, Boston, MA, 02115, USA
| | - Aita Sene
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Winnie Mkandawire
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- University of Massachusetts Medical School, Worcester, MA, USA
| | - Awa B Deme
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Tolla Ndiaye
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Mouhamad Sy
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Amy Gaye
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Younouss Diedhiou
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Amadou M Mbaye
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Ibrahima Ndiaye
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Jules Gomis
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Médoune Ndiop
- Programme National de Lutte contre le Paludisme (PNLP), Ministère de la Santé, Dakar Fann, Senegal
| | - Doudou Sene
- Programme National de Lutte contre le Paludisme (PNLP), Ministère de la Santé, Dakar Fann, Senegal
| | | | - Bronwyn MacInnis
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Stephen F Schaffner
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Daniel J Park
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Aida S Badiane
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Andres Colubri
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- University of Massachusetts Medical School, Worcester, MA, USA
| | - Mouhamadou Ndiaye
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Ngayo Sy
- Service de Lutte Anti Parasitaire, Thies, Senegal
| | - Pardis C Sabeti
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Daouda Ndiaye
- Centre International de recherche, de formation en Génomique Appliquée et de Surveillance Sanitaire (CIGASS), Dakar, Senegal
| | - Katherine J Siddle
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, USA
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13
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Moussa RA, Papa Mze N, Arreh HY, Hamoud AA, Alaleh KM, Omar ARY, Abdi WO, Guelleh SK, Abdi AIA, Aboubaker MH, Basco LK, Khaireh BA, Bogreau H. Molecular investigation of malaria-infected patients in Djibouti city (2018-2021). Malar J 2023; 22:147. [PMID: 37131225 PMCID: PMC10154177 DOI: 10.1186/s12936-023-04546-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 03/30/2023] [Indexed: 05/04/2023] Open
Abstract
BACKGROUND The Republic of Djibouti is a malaria endemic country that was in pre-elimination phase in 2006-2012. From 2013, however, malaria has re-emerged in the country, and its prevalence has been increasing every year. Given the co-circulation of several infectious agents in the country, the assessment of malaria infection based on microscopy or histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDT) has shown its limitations. This study, therefore, aimed to assess the prevalence of malaria among febrile patients in Djibouti city using more robust molecular tools. METHODS All suspected malaria cases reported to be microscopy-positive were randomly sampled (n = 1113) and included in four health structures in Djibouti city over a 4-year period (2018-2021), mainly during the malaria transmission season (January-May). Socio-demographic information was collected, and RDT was performed in most of the included patients. The diagnosis was confirmed by species-specific nested polymerase chain reaction (PCR). Data were analysed using Fisher's exact test and kappa statistics. RESULTS In total, 1113 patients with suspected malaria and available blood samples were included. PCR confirmed that 788/1113 (70.8%) were positive for malaria. Among PCR-positive samples, 656 (83.2%) were due to Plasmodium falciparum, 88 (11.2%) Plasmodium vivax, and 44 (5.6%) P. falciparum/P. vivax mixed infections. In 2020, P. falciparum infections were confirmed by PCR in 50% (144/288) of negative RDTs. After the change of RDT in 2021, this percentage decreased to 17%. False negative RDT results were found more frequently (P < 0.05) in four districts of Djibouti city (Balbala, Quartier 7, Quartier 6, and Arhiba). Malaria occurred less frequently in regular bed net users than in non-users (odds ratio [OR]: 0.62, 95% confidence interval [CI]: 0.42-0.92). CONCLUSIONS The present study confirmed the high prevalence of falciparum malaria and, to a lesser extent, vivax malaria. Nevertheless, 29% of suspected malaria cases were misdiagnosed by microscopy and/or RDT. There is a need to strengthen the capacity for diagnosis by microscopy and to evaluate the possible role of P. falciparum hrp2 gene deletion, which leads to false negative cases of P. falciparum.
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Affiliation(s)
- Rahma Abdi Moussa
- Université d'Aix Marseille, IRD, AP-HM, SSA, VITROME, Marseille, France
- IHU-Méditerranée Infection, Marseille, France
- Laboratoire de Diagnostic, Caisse Nationale de Sécurité Sociale (CNSS), Djibouti, Republic of Djibouti
| | - Nasserdine Papa Mze
- Université d'Aix Marseille, IRD, AP-HM, SSA, VITROME, Marseille, France
- IHU-Méditerranée Infection, Marseille, France
| | - Houssein Yonis Arreh
- Laboratoire National de Référence, Hôpital Général Peltier, Ministère de La Santé, Djibouti, Republic of Djibouti
| | - Aicha Abdillahi Hamoud
- Laboratoire de Diagnostic, Caisse Nationale de Sécurité Sociale (CNSS), Djibouti, Republic of Djibouti
| | - Kahiya Mohamed Alaleh
- Laboratoire de Diagnostic, Caisse Nationale de Sécurité Sociale (CNSS), Djibouti, Republic of Djibouti
| | - Abdoul-Razak Yonis Omar
- Laboratoire de Diagnostic, Centre de Santé Communautaire d'Einguela, Ministère de La Santé, Djibouti, Republic of Djibouti
| | - Warsama Osman Abdi
- Caisse Nationale de Sécurité Sociale (CNSS), Djibouti, Republic of Djibouti
| | - Samatar Kayad Guelleh
- Programme National de Lutte Contre Le Paludisme, Direction des Programmes de Santé Prioritaires, Ministère de La Santé, Djibouti, Republic of Djibouti
| | - Abdoul-Ilah Ahmed Abdi
- Service de Santé des Armées, Présidence de la République, Djibouti, Republic of Djibouti
| | - Mohamed Houmed Aboubaker
- Laboratoire de Diagnostic, Caisse Nationale de Sécurité Sociale (CNSS), Djibouti, Republic of Djibouti
| | - Leonardo K Basco
- Université d'Aix Marseille, IRD, AP-HM, SSA, VITROME, Marseille, France
- IHU-Méditerranée Infection, Marseille, France
| | - Bouh Abdi Khaireh
- UNDP Djibouti, Global Fund to Fight AIDS-TB-Malaria, Djibouti, Republic of Djibouti
| | - Hervé Bogreau
- Université d'Aix Marseille, IRD, AP-HM, SSA, VITROME, Marseille, France.
- IHU-Méditerranée Infection, Marseille, France.
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France.
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Low Prevalence of Plasmodium falciparum Histidine-Rich Protein 2 and 3 Gene Deletions—A Multiregional Study in Central and West Africa. Pathogens 2023; 12:pathogens12030455. [PMID: 36986377 PMCID: PMC10054520 DOI: 10.3390/pathogens12030455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/02/2023] [Accepted: 03/07/2023] [Indexed: 03/15/2023] Open
Abstract
Plasmodium falciparum parasites carrying deletions of histidine-rich protein 2 and 3 genes, pfhrp2 and pfhrp3, respectively, are likely to escape detection via HRP2-based rapid diagnostic tests (RDTs) and, consequently, treatment, posing a major risk to both the health of the infected individual and malaria control efforts. This study assessed the frequency of pfhrp2- and pfhrp3-deleted strains at four different study sites in Central Africa (number of samples analyzed: Gabon N = 534 and the Republic of Congo N = 917) and West Africa (number of samples analyzed: Nigeria N = 466 and Benin N = 120) using a highly sensitive multiplex qPCR. We found low prevalences for pfhrp2 (1%, 0%, 0.03% and 0) and pfhrp3 single deletions (0%, 0%, 0.03% and 0%) at all study sites (Gabon, the Republic of Congo, Nigeria and Benin, respectively). Double-deleted P. falciparum were only found in Nigeria in 1.6% of all internally controlled samples. The results of this pilot investigation do not point towards a high risk for false-negative RDT results due to pfhrp2/pfhrp3 deletions in Central and West African regions. However, as this scenario can change rapidly, continuous monitoring is essential to ensure that RDTs remain a suitable tool for the malaria diagnostic strategy.
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15
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Kattenberg JH, Fernandez-Miñope C, van Dijk NJ, Llacsahuanga Allcca L, Guetens P, Valdivia HO, Van geertruyden JP, Rovira-Vallbona E, Monsieurs P, Delgado-Ratto C, Gamboa D, Rosanas-Urgell A. Malaria Molecular Surveillance in the Peruvian Amazon with a Novel Highly Multiplexed Plasmodium falciparum AmpliSeq Assay. Microbiol Spectr 2023; 11:e0096022. [PMID: 36840586 PMCID: PMC10101074 DOI: 10.1128/spectrum.00960-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 08/02/2022] [Indexed: 02/24/2023] Open
Abstract
Molecular surveillance for malaria has great potential to support national malaria control programs (NMCPs). To bridge the gap between research and implementation, several applications (use cases) have been identified to align research, technology development, and public health efforts. For implementation at NMCPs, there is an urgent need for feasible and cost-effective tools. We designed a new highly multiplexed deep sequencing assay (Pf AmpliSeq), which is compatible with benchtop sequencers, that allows high-accuracy sequencing with higher coverage and lower cost than whole-genome sequencing (WGS), targeting genomic regions of interest. The novelty of the assay is its high number of targets multiplexed into one easy workflow, combining population genetic markers with 13 nearly full-length resistance genes, which is applicable for many different use cases. We provide the first proof of principle for hrp2 and hrp3 deletion detection using amplicon sequencing. Initial sequence data processing can be performed automatically, and subsequent variant analysis requires minimal bioinformatic skills using any tabulated data analysis program. The assay was validated using a retrospective sample collection (n = 254) from the Peruvian Amazon between 2003 and 2018. By combining phenotypic markers and a within-country 28-single-nucleotide-polymorphism (SNP) barcode, we were able to distinguish different lineages with multiple resistance haplotypes (in dhfr, dhps, crt and mdr1) and hrp2 and hrp3 deletions, which have been increasing in recent years. We found no evidence to suggest the emergence of artemisinin (ART) resistance in Peru. These findings indicate a parasite population that is under drug pressure but is susceptible to current antimalarials and demonstrate the added value of a highly multiplexed molecular tool to inform malaria strategies and surveillance systems. IMPORTANCE While the power of next-generation sequencing technologies to inform and guide malaria control programs has become broadly recognized, the integration of genomic data for operational incorporation into malaria surveillance remains a challenge in most countries where malaria is endemic. The main obstacles include limited infrastructure, limited access to high-throughput sequencing facilities, and the need for local capacity to run an in-country analysis of genomes at a large-enough scale to be informative for surveillance. In addition, there is a lack of standardized laboratory protocols and automated analysis pipelines to generate reproducible and timely results useful for relevant stakeholders. With our standardized laboratory and bioinformatic workflow, malaria genetic surveillance data can be readily generated by surveillance researchers and malaria control programs in countries of endemicity, increasing ownership and ensuring timely results for informed decision- and policy-making.
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Affiliation(s)
| | - Carlos Fernandez-Miñope
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Norbert J. van Dijk
- Institute of Tropical Medicine Antwerp, Biomedical Sciences Department, Antwerp, Belgium
| | - Lidia Llacsahuanga Allcca
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Pieter Guetens
- Institute of Tropical Medicine Antwerp, Biomedical Sciences Department, Antwerp, Belgium
| | - Hugo O. Valdivia
- Department of Parasitology, U.S. Naval Medical Research Unit No. 6 (NAMRU-6), Lima, Peru
| | | | - Eduard Rovira-Vallbona
- Institute of Tropical Medicine Antwerp, Biomedical Sciences Department, Antwerp, Belgium
| | - Pieter Monsieurs
- Institute of Tropical Medicine Antwerp, Biomedical Sciences Department, Antwerp, Belgium
| | - Christopher Delgado-Ratto
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Dionicia Gamboa
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anna Rosanas-Urgell
- Institute of Tropical Medicine Antwerp, Biomedical Sciences Department, Antwerp, Belgium
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Okanda D, Ndwiga L, Osoti V, Achieng N, Wambua J, Ngetsa C, Lubell-Doughtie P, Shankar A, Bejon P, Ochola-Oyier LI. Low frequency of Plasmodium falciparum hrp2/3 deletions from symptomatic infections at a primary healthcare facility in Kilifi, Kenya. FRONTIERS IN EPIDEMIOLOGY 2023; 3:1083114. [PMID: 38455911 PMCID: PMC10910971 DOI: 10.3389/fepid.2023.1083114] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 01/23/2023] [Indexed: 03/09/2024]
Abstract
There is a growing concern for malaria control in the Horn of Africa region due to the spread and rise in the frequency of Plasmodium falciparum Histidine-rich Protein (hrp) 2 and 3 deletions. Parasites containing these gene deletions escape detection by the major PfHRP2-based rapid diagnostic test. In this study, the presence of Pfhrp2/3 deletions was examined in uncomplicated malaria patients in Kilifi County, from a region of moderate-high malaria transmission. 345 samples were collected from the Pingilikani dispensary in 2019/2020 during routine malaria care for patients attending this primary health care facility. The Carestart™ RDT and microscopy were used to test for malaria. In addition, qPCR was used to confirm the presence of parasites. In total, 249 individuals tested positive for malaria by RDT, 242 by qPCR, and 170 by microscopy. 11 samples that were RDT-negative and microscopy positive and 25 samples that were qPCR-positive and RDT-negative were considered false negative tests and were examined further for Pfhrp2/3 deletions. Pfhrp2/3-negative PCR samples were further genotyped at the dihydrofolate reductase (Pfdhfr) gene which served to further confirm that parasite DNA was present in the samples. The 242 qPCR-positive samples (confirmed the presence of DNA) were also selected for Pfhrp2/3 genotyping. To determine the frequency of false negative results in low parasitemia samples, the RDT- and qPCR-negative samples were genotyped for Pfdhfr before testing for Pfhrp2/3. There were no Pfhrp2 and Pfhrp3 negative but positive for dhfr parasites in the 11 (RDT negative and microscopy positive) and 25 samples (qPCR-positive and RDT-negative). In the larger qPCR-positive sample set, only 5 samples (2.1%) were negative for both hrp2 and hrp3, but positive for dhfr. Of the 5 samples, there were 4 with more than 100 parasites/µl, suggesting true hrp2/3 deletions. These findings revealed that there is currently a low prevalence of Pfhrp2 and Pfhrp3 deletions in the health facility in Kilifi. However, routine monitoring in other primary health care facilities across the different malaria endemicities in Kenya is urgently required to ensure appropriate use of malaria RDTs.
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Affiliation(s)
- Dorcas Okanda
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Leonard Ndwiga
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Victor Osoti
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Nicole Achieng
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Juliana Wambua
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Caroline Ngetsa
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Anuraj Shankar
- Nuffield Department of Medicine, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Philip Bejon
- Biosciences Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
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17
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Mwangonela ZE, Ye Y, Rachel Q, Msuya HM, Mwamlima TG, Mswata SS, Chaki PP, Kimaro EG, Mweya CN, Mpina MG, Mwangoka GW. Field evaluation of the novel One Step Malaria Pf and Pf/Pv rapid diagnostic tests and the proportion of HRP-2 gene deletion identified on samples collected in the Pwani region, Tanzania. BULLETIN OF THE NATIONAL RESEARCH CENTRE 2023; 47:17. [PMID: 36776799 PMCID: PMC9904258 DOI: 10.1186/s42269-023-00992-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Background Malaria rapid diagnostic tests (mRDTs) have played an important role in the early detection of clinical malaria in an endemic area. While several mRDTs are currently on the market, the availability of mRDTs with high sensitivity and specificity will merit the fight against malaria. We evaluated the field performance of a novel One Step Malaria (P.f/P.v) Tri-line and One Step Malaria (P.f) rapid test kits in Pwani, Tanzania. Methods In a cross-sectional study conducted in Bagamoyo and Kibiti districts in Tanzania, symptomatic patients were tested using the SD BIOLINE, One Step Malaria (P.f/P.v) Tri-line and One Step Malaria (P.f) rapid test kits, microscope, and quantitative Polymerase Chain Reaction (qPCR). An additional qPCR assay was carried out to detect Histidine-Rich Protein 2 (HRP-2) gene deletion on mRDT negative but microscope and qPCR positive samples. Microscope results confirmed by qPCR were used for analysis, where qPCR was used as a reference method. Results The sensitivity and specificity of One Step P.f/P.v Tri-line mRDTs were 96.0% (CI 93.5-97.7%) and 98.3% (CI 96.8-99.2%), respectively. One Step P.f mRDT had sensitivity and specificity of 95.2% (CI 92.5-97.1%) and 97.9% (CI 96.3-99.0%) respectively. Positive predictive value (PPV) was 97.6% (CI 95.4-98.7%) and negative predictive value (NPV) was 96.2% (CI 95.5-98.3%) for the One Step P.f/P.v Tri-line mRDTs respectively, while One Step P.f mRDT had positive predictive value (PPV) and negative predictive value (NPV) of 97.0% (CI 94.8-98.3%) and 96.7 (CI 94.9-97.9%) respectively. 9.8% (CI 7.84-11.76) of all samples tested and reported to be malaria-negative by mRDT had HRP-2 gene deletion. Conclusion One Step Malaria P.f/P.v Tri-line and One Step Malaria P.f rapid test kits have similar sensitivity and specificity as the standard mRDT that is currently in the market, demonstrating the potential to contribute in the fight against malaria in endemic settings. However, the identified malaria parasites population with HRP-2 gene deletion pose a threat to the current mRDT usability in the field and warrants further investigations.
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Affiliation(s)
- Zena E. Mwangonela
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
- The Nelson Mandela African Institution of Science and Technology, P.O.Box 447, Arusha, Tanzania
| | - Young Ye
- InTec Products, Inc., 332 Xinguang Road Xinyang Industrial Area, Haicang, Xiamen City, 361022 China
| | - Qin Rachel
- InTec Products, Inc., 332 Xinguang Road Xinyang Industrial Area, Haicang, Xiamen City, 361022 China
| | - Hajirani M. Msuya
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
| | - Tunu G. Mwamlima
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
- The Nelson Mandela African Institution of Science and Technology, P.O.Box 447, Arusha, Tanzania
| | - Sarah S. Mswata
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
| | - Prosper P. Chaki
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
| | - Ester G. Kimaro
- The Nelson Mandela African Institution of Science and Technology, P.O.Box 447, Arusha, Tanzania
| | - Clement N. Mweya
- Univesity of Dar Es Salaam, Mbeya College of Health and Allied Science, P.O.Box 608, Mbeya, Tanzania
| | | | - Grace W. Mwangoka
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
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18
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Agaba BB, Rugera SP, Mpirirwe R, Atekat M, Okubal S, Masereka K, Erionu M, Adranya B, Nabirwa G, Odong PB, Mukiibi Y, Ssewanyana I, Nabadda S, Muwanguzi E. Asymptomatic malaria infection, associated factors and accuracy of diagnostic tests in a historically high transmission setting in Northern Uganda. Malar J 2022; 21:392. [PMID: 36550492 PMCID: PMC9783970 DOI: 10.1186/s12936-022-04421-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Asymptomatic malaria infections are important parasite reservoirs and could sustain transmission in the population, but they are often unreported. A community-based survey was conducted to investigate the prevalence and factors associated with asymptomatic malaria infections in a historically high transmission setting in northern Uganda. METHODS Using a cross-sectional design, 288 children aged 2-15 years were enrolled and tested for the presence of malaria parasites using rapid diagnostic tests (RDTs) and blood smear microscopy between January to May 2022. Statistical analysis was performed using the exact binomial and Fisher's exact test with p ≤ 0.05 indicating significance. The logistic regression was used to explore factors associated with asymptomatic malaria infections. RESULTS Overall, the prevalence of asymptomatic infection was 34.7% (95% CI 29.2-40.5) with the highest observed in children 5-10 years 45.9% (95% CI 35.0-57.0). Gweri village accounted for 39.1% (95% CI 27.6-51.6) of malaria infections. Median parasite density was 1500 parasites/µl of blood. Plasmodium falciparum was the dominant species (86%) followed by Plasmodium malariae (5%). Factors associated with asymptomatic malaria infection were sleeping under mosquito net (Adjusted Odds Ratio (aOR) 0.27; 95% CI 0.13-0.56), p = 0.001 and presence of village health teams (VHTs) (aOR 0.02; 95% CI 0.01-0.45), p = 0.001. Sensitivity and specificity were higher for the P. falciparum/pLDH RDTs compared to HRP2-only RDTs, 90% (95% CI 86.5-93.5) and 95.2% (95% CI 92.8-97.7), p = 0.001, respectively. CONCLUSION Asymptomatic malaria infections were present in the study population and this varied with place and person in the different age groups. Plasmodium falciparum was the dominant parasite species however the presence of P. malariae and Plasmodium ovale was observed, which may have implication for the choice and deployment of diagnostic tools. Individuals who slept under mosquito net or had presence of functional VHTs were less likely to have asymptomatic malaria infection. P.f/pLDH RDTs performed better than the routinely used HRP2 RDTs. In view of these findings, investigation and reporting of asymptomatic malaria reservoirs through community surveys is recommended for accurate disease burden estimate and better targeting of control.
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Affiliation(s)
- Bosco B. Agaba
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda ,grid.415705.2National Malaria Control Division, Ministry of Health, Kampala, Uganda ,National Malaria Reference Laboratory, Central Public Health Laboratory Services, Kampala, Uganda ,grid.463352.50000 0004 8340 3103Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Simon P. Rugera
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Ruth Mpirirwe
- grid.11194.3c0000 0004 0620 0548Department of Statistics, Makerere University, Kampala, Uganda
| | - Martha Atekat
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Samuel Okubal
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Khalid Masereka
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Miseal Erionu
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Bosco Adranya
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Gertrude Nabirwa
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Patrick B. Odong
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Yasin Mukiibi
- Uganda Institute of Allied and Management Sciences, Kampala, Uganda
| | - Isaac Ssewanyana
- National Malaria Reference Laboratory, Central Public Health Laboratory Services, Kampala, Uganda ,grid.463352.50000 0004 8340 3103Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Susan Nabadda
- National Malaria Reference Laboratory, Central Public Health Laboratory Services, Kampala, Uganda
| | - Enoch Muwanguzi
- grid.33440.300000 0001 0232 6272Department of Medical Laboratory Science, Mbarara University of Science and Technology, Mbarara, Uganda ,Uganda Institute of Allied and Management Sciences, Kampala, Uganda
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19
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Stabler TC, Dwivedi A, Shrestha B, Joshi S, Schindler T, Ouattara A, García GA, Daubenberger C, Silva JC. Gene Coverage Count and Classification (GC 3): a locus sequence coverage assessment tool using short-read whole genome sequencing data, and its application to identify and classify histidine-rich protein 2 and 3 deletions in Plasmodium falciparum. Malar J 2022; 21:357. [PMID: 36447234 PMCID: PMC9706933 DOI: 10.1186/s12936-022-04376-3] [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: 07/15/2022] [Accepted: 11/10/2022] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND The ability of malaria rapid diagnostic tests (RDTs) to effectively detect active infections is being compromised by the presence of malaria strains with genomic deletions at the hrp2 and hrp3 loci, encoding the antigens most commonly targeted in diagnostics for Plasmodium falciparum detection. The presence of such deletions can be determined in publically available P. falciparum whole genome sequencing (WGS) datasets. A computational approach was developed and validated, termed Gene Coverage Count and Classification (GC3), to analyse genome-wide sequence coverage data and provide informative outputs to assess presence and coverage profile of a target locus in WGS data. GC3 was applied to detect deletions at hrp2 and hrp3 (hrp2/3) and flanking genes in different geographic regions and across time points. METHODS GC3 uses Python and R scripts to extract locus read coverage metrics from mapped WGS data according to user-defined parameters and generates relevant tables and figures. GC3 was tested using WGS data for laboratory reference strains with known hrp2/3 genotypes, and its results compared to those of a hrp2/3-specific qPCR assay. Samples with at least 25% of coding region positions with zero coverage were classified as having a deletion. Publicly available sequence data was analysed and compared with published deletion frequency estimates. RESULTS GC3 results matched the expected coverage of known laboratory reference strains. Agreement between GC3 and a hrp2/3-specific qPCR assay reported for 19/19 (100%) hrp2 deletions and 18/19 (94.7%) hrp3 deletions. Among Cambodian (n = 127) and Brazilian (n = 20) WGS datasets, which had not been previously analysed for hrp2/3 deletions, GC3 identified hrp2 deletions in three and four samples, and hrp3 deletions in 10 and 15 samples, respectively. Plots of hrp2/3 coding regions, grouped by year of sample collection, showed a decrease in median standardized coverage among Malawian samples (n = 150) suggesting the importance of a careful, properly controlled follow up to determine if an increase in frequency of deletions has occurred between 2007-2008 and 2014-2015. Among Malian (n = 90) samples, median standardized coverage was lower in 2002 than 2010, indicating widespread deletions present at the gene locus in 2002. CONCLUSIONS The GC3 tool accurately classified hrp2/3 deletions and provided informative tables and figures to analyse targeted gene coverage. GC3 is an appropriate tool when performing preliminary and exploratory assessment of locus coverage data.
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Affiliation(s)
- Thomas C Stabler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.
- University of Basel, Basel, Switzerland.
| | - Ankit Dwivedi
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Biraj Shrestha
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sudhaunshu Joshi
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Tobias Schindler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Amed Ouattara
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - Claudia Daubenberger
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Joana C Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA.
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA.
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20
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Ansah F, Krampa F, Donkor JK, Owusu-Appiah C, Ashitei S, Kornu VE, Danku RK, Chirawurah JD, Awandare GA, Aniweh Y, Kanyong P. Ultrasensitive electrochemical genosensors for species-specific diagnosis of malaria. Electrochim Acta 2022; 429:140988. [PMID: 36225971 PMCID: PMC9472471 DOI: 10.1016/j.electacta.2022.140988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/02/2022] [Accepted: 08/07/2022] [Indexed: 11/21/2022]
Abstract
The absence of reliable species-specific diagnostic tools for malaria at point-of-care (POC) remains a major setback towards effective disease management. This is partly due to the limited sensitivity and specificity of the current malaria POC diagnostic kits especially in cases of low-density parasitaemia and mixed species infections. In this study, we describe the first label-free DNA-based genosensors based on electrochemical impedance spectroscopy (EIS) for species-specific detection of P. falciparum, P. malariae and P. ovale. The limits of detection (LOD) for the three species-specific genosensors were down in attomolar concentrations ranging from 18.7 aM to 43.6 aM, which is below the detection limits of previously reported malaria genosensors. More importantly, the diagnostic performance of the three genosensors were compared to quantitative real-time polymerase chain reaction (qPCR) assays using purified genomic DNA and the paired whole blood lysates from clinical samples. Remarkably, all the qPCR-positive purified genomic DNA samples were correctly identified by the genosensors indicating 100% sensitivity for each of the three malaria species. The specificities of the three genosensors ranged from 66.7% to 100.0% with a Therapeutic Turnaround Time (TTAT) within 30 min, which is comparable to the TTAT of current POC diagnostic tools for malaria. This work represents a significant step towards the development of accurate and rapid species-specific nucleic acid-based toolkits for the diagnosis of malaria at the POC.
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Affiliation(s)
- Felix Ansah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Francis Krampa
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge,CB3 0AS, United Kingdom
| | - Jacob K. Donkor
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Caleb Owusu-Appiah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Sarah Ashitei
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Victor E. Kornu
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Reinhard K. Danku
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Jersley D. Chirawurah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Yaw Aniweh
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Prosper Kanyong
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Siemens Healthineers, Siemens Healthcare Diagnostics Products Ltd, Llanberis, Gwynedd LL55 4EL, United Kingdom
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21
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Abstract
IMPORTANCE Malaria is caused by protozoa parasites of the genus Plasmodium and is diagnosed in approximately 2000 people in the US each year who have returned from visiting regions with endemic malaria. The mortality rate from malaria is approximately 0.3% in the US and 0.26% worldwide. OBSERVATIONS In the US, most malaria is diagnosed in people who traveled to an endemic region. More than 80% of people diagnosed with malaria in the US acquired the infection in Africa. Of the approximately 2000 people diagnosed with malaria in the US in 2017, an estimated 82.4% were adults and about 78.6% were Black or African American. Among US residents diagnosed with malaria, 71.7% had not taken malaria chemoprophylaxis during travel. In 2017 in the US, P falciparum was the species diagnosed in approximately 79% of patients, whereas P vivax was diagnosed in an estimated 11.2% of patients. In 2017 in the US, severe malaria, defined as vital organ involvement including shock, pulmonary edema, significant bleeding, seizures, impaired consciousness, and laboratory abnormalities such as kidney impairment, acidosis, anemia, or high parasitemia, occurred in approximately 14% of patients, and an estimated 0.3% of those receiving a diagnosis of malaria in the US died. P falciparum has developed resistance to chloroquine in most regions of the world, including Africa. First-line therapy for P falciparum malaria in the US is combination therapy that includes artemisinin. If P falciparum was acquired in a known chloroquine-sensitive region such as Haiti, chloroquine remains an alternative option. When artemisinin-based combination therapies are not available, atovaquone-proguanil or quinine plus clindamycin is used for chloroquine-resistant malaria. P vivax, P ovale, P malariae, and P knowlesi are typically chloroquine sensitive, and treatment with either artemisinin-based combination therapy or chloroquine for regions with chloroquine-susceptible infections for uncomplicated malaria is recommended. For severe malaria, intravenous artesunate is first-line therapy. Treatment of mild malaria due to a chloroquine-resistant parasite consists of a combination therapy that includes artemisinin or chloroquine for chloroquine-sensitive malaria. P vivax and P ovale require additional therapy with an 8-aminoquinoline to eradicate the liver stage. Several options exist for chemoprophylaxis and selection should be based on patient characteristics and preferences. CONCLUSIONS AND RELEVANCE Approximately 2000 cases of malaria are diagnosed each year in the US, most commonly in travelers returning from visiting endemic areas. Prevention and treatment of malaria depend on the species and the drug sensitivity of parasites from the region of acquisition. Intravenous artesunate is first-line therapy for severe malaria.
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Affiliation(s)
- Johanna P Daily
- Department of Medicine (Infectious Diseases), Albert Einstein College of Medicine, Bronx, New York
| | - Aurelia Minuti
- D. Samuel Gottesman Library, Albert Einstein College of Medicine, Bronx, New York
| | - Nazia Khan
- Department of Medicine (Infectious Diseases), Albert Einstein College of Medicine, Bronx, New York
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Mayor A, da Silva C, Rovira-Vallbona E, Roca-Feltrer A, Bonnington C, Wharton-Smith A, Greenhouse B, Bever C, Chidimatembue A, Guinovart C, Proctor JL, Rodrigues M, Canana N, Arnaldo P, Boene S, Aide P, Enosse S, Saute F, Candrinho B. Prospective surveillance study to detect antimalarial drug resistance, gene deletions of diagnostic relevance and genetic diversity of Plasmodium falciparum in Mozambique: protocol. BMJ Open 2022; 12:e063456. [PMID: 35820756 PMCID: PMC9274532 DOI: 10.1136/bmjopen-2022-063456] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION Genomic data constitute a valuable adjunct to routine surveillance that can guide programmatic decisions to reduce the burden of infectious diseases. However, genomic capacities remain low in Africa. This study aims to operationalise a functional malaria molecular surveillance system in Mozambique for guiding malaria control and elimination. METHODS AND ANALYSES This prospective surveillance study seeks to generate Plasmodium falciparum genetic data to (1) monitor molecular markers of drug resistance and deletions in rapid diagnostic test targets; (2) characterise transmission sources in low transmission settings and (3) quantify transmission levels and the effectiveness of antimalarial interventions. The study will take place across 19 districts in nine provinces (Maputo city, Maputo, Gaza, Inhambane, Niassa, Manica, Nampula, Zambézia and Sofala) which span a range of transmission strata, geographies and malaria intervention types. Dried blood spot samples and rapid diagnostic tests will be collected across the study districts in 2022 and 2023 through a combination of dense (all malaria clinical cases) and targeted (a selection of malaria clinical cases) sampling. Pregnant women attending their first antenatal care visit will also be included to assess their value for molecular surveillance. We will use a multiplex amplicon-based next-generation sequencing approach targeting informative single nucleotide polymorphisms, gene deletions and microhaplotypes. Genetic data will be incorporated into epidemiological and transmission models to identify the most informative relationship between genetic features, sources of malaria transmission and programmatic effectiveness of new malaria interventions. Strategic genomic information will be ultimately integrated into the national malaria information and surveillance system to improve the use of the genetic information for programmatic decision-making. ETHICS AND DISSEMINATION The protocol was reviewed and approved by the institutional (CISM) and national ethics committees of Mozambique (Comité Nacional de Bioética para Saúde) and Spain (Hospital Clinic of Barcelona). Project results will be presented to all stakeholders and published in open-access journals. TRIAL REGISTRATION NUMBER NCT05306067.
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Affiliation(s)
- Alfredo Mayor
- Centro de Investigação em Saúde de Manhiça, Manhiça, Maputo, Mozambique
- Barcelona Institute for Global Health, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
- Spanish Consortium for Research in Epidemiology and Public Health (CIBERESP), Madrid, Spain
- Department of Physiologic Sciences, Faculty of Medicine, Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Clemente da Silva
- Centro de Investigação em Saúde de Manhiça, Manhiça, Maputo, Mozambique
| | - Eduard Rovira-Vallbona
- Barcelona Institute for Global Health, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | | | | | | | - Bryan Greenhouse
- Department of Medicine, University of California San Francisco, San Francisco, California, USA
| | - Caitlin Bever
- Bill & Melinda Gates Foundation, Seattle, Washington, USA
| | | | - Caterina Guinovart
- Barcelona Institute for Global Health, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | | | | | | | | | - Simone Boene
- Centro de Investigação em Saúde de Manhiça, Manhiça, Maputo, Mozambique
| | - Pedro Aide
- Centro de Investigação em Saúde de Manhiça, Manhiça, Maputo, Mozambique
- Instituto Nacional de Saúde, Maputo, Mozambique
| | | | - Francisco Saute
- Centro de Investigação em Saúde de Manhiça, Manhiça, Maputo, Mozambique
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Eyong EM, Etutu SJM, Jerome FC, Nyasa RB, Kwenti TE, Moyeh MN. Plasmodium falciparum histidine-rich protein 2 and 3 gene deletion in the Mount Cameroon region. IJID REGIONS (ONLINE) 2022; 3:300-307. [PMID: 35755467 PMCID: PMC9216387 DOI: 10.1016/j.ijregi.2022.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 12/04/2022]
Abstract
pfhrp2/3 gene deletions occur in parasite populations in the Mount Cameroon region pfhrp2-negative parasites are the more common in the Mount Cameroon region pfhrp2/3-negative parasites negatively impact malaria rapid diagnostic test success
Objective Plasmodium falciparum produces histidine-rich protein 2/3 (Pfhrp2/3) genes that accumulate to high levels in the bloodstream and serve as a diagnostic and prognostic marker for falciparum malaria. Pfhrp2/3 gene deletions may lead to false-negative rapid diagnostic test (RDT) results. We aimed to determine the prevalence of pfhrp2/3 gene deletions in P. falciparum isolates and the implications for RDT use in the Mount Cameroon region. Methods A cross-sectional hospital-based study with malaria diagnosis performed using microscopy, RDT and nested polymerase chain reaction (nPCR). In total, 324 P. falciparum microscopy positive individuals were enrolled and their samples confirmed positive for P. falciparum using 18SrRNA PCR. Samples that gave false-negative RDT results were analyzed to detect pfhrp2/3 exon 2 deletions. Results Of 324 positive microscopic and nPCR samples, 16 gave RDT false-negative results. Among the 324 P. falciparum positive isolates, exon 2 deletions were observed in 2.2% (7 of 324); 3 were negative for pfhrp2 gene, 2 for pfhrp3, and 2 for both pfhrp2 and pfhrp3 (double deletions). Conclusion P. falciparum isolates with pfhrp2/3 gene deletion were present in the parasite populations and may contribute to the RDT false-negative results in the Mount Cameroon region.
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Affiliation(s)
- Esum Mathias Eyong
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, South West Region, Cameroon
| | - Sophie Jose Molua Etutu
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, South West Region, Cameroon
| | - Fru-Cho Jerome
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, South West Region, Cameroon
| | - Raymond Babila Nyasa
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, South West Region, Cameroon
| | - Tebit Emmanuel Kwenti
- Department of Medical Laboratory Sciences, Faculty of Health Sciences, University of Buea, P.O. Box 63, Buea, South West Region, Cameroon
| | - Marcel N Moyeh
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O. Box 63, Buea, South West Region of Cameroon
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24
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Malaria and Helminthic Co-Infection during Pregnancy in Sub-Saharan Africa: A Systematic Review and Meta-Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095444. [PMID: 35564842 PMCID: PMC9101176 DOI: 10.3390/ijerph19095444] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 12/22/2022]
Abstract
Malaria and helminthic co-infection during pregnancy causes fetomaternal haemorrhage and foetal growth retardation. This study determined the pooled burden of pregnancy malaria and helminthic co-infection in sub-Saharan Africa. CINAHL, EMBASE, Google Scholar, Scopus, PubMed, and Web of Science databases were used to retrieve data from the literature, without restricting language and publication year. The Joanna Briggs Institute’s critical appraisal tool for prevalence studies was used for quality assessment. STATA Version 14.0 was used to conduct the meta-analysis. The I2 statistics and Egger’s test were used to test heterogeneity and publication bias. The random-effects model was used to estimate the pooled prevalence at a 95% confidence interval (CI). The review protocol has been registered in PROSPERO, with the number CRD42019144812. In total, 24 studies (n = 14,087 participants) were identified in this study. The pooled analysis revealed that 20% of pregnant women were co-infected by malaria and helminths in sub-Saharan Africa. The pooled prevalence of malaria and helminths were 33% and 35%, respectively. The most prevalent helminths were Hookworm (48%), Ascaris lumbricoides (37%), and Trichuris trichiura (15%). Significantly higher malaria and helminthic co-infection during pregnancy were observed. Health systems in sub-Saharan Africa must implement home-grown innovative solutions to underpin context-specific policies for the early initiation of effective intermittent preventive therapy.
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25
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Deletions of the Plasmodium falciparum histidine-rich protein 2/3 genes are common in field isolates from north-eastern Tanzania. Sci Rep 2022; 12:5802. [PMID: 35388127 PMCID: PMC8987040 DOI: 10.1038/s41598-022-09878-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/30/2022] [Indexed: 11/26/2022] Open
Abstract
Plasmodium falciparum parasites lacking histidine-rich protein 2 and 3 (pfhrp2/3) genes have been reported in several parts of the world. These deletions are known to compromise the effectiveness of HRP2-based malaria rapid diagnostic tests (HRP2-RDT). The National Malaria Control Programme (NMCP) in Tanzania adopted HRP2-RDTs as a routine tool for malaria diagnosis in 2009 replacing microscopy in many Health facilities. We investigated pfhrp2/3 deletions in 122 samples from two areas with diverse malaria transmission intensities in Northeastern Tanzania. Pfhrp2 deletion was confirmed in 1.6% of samples while pfhrp3 deletion was confirmed in 50% of samples. We did not find parasites with both pfhrp2 and pfhrp3 deletions among our samples. Results from this study highlight the need for systematic surveillance of pfhrp2/3 deletions in Tanzania to understand their prevalence and determine their impact on the performance of mRDT.
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26
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Kumari MS, Sharma S, Bhardwaj N, Kumar S, Ahmed MZ, Pande V, Anvikar AR. Pfhrp2/3 gene deletion and genetic variation in PfHRP2-based RDTs with P. falciparum positive samples from India and its implication on malaria control. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2022; 99:105232. [PMID: 35114396 DOI: 10.1016/j.meegid.2022.105232] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 01/08/2022] [Accepted: 01/25/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND Recent studies have documented Pfhrp2/3 gene deletion globally as one of the biological threats in the fight against malaria. For malaria diagnosis, PfHRP2 based RDTs are most widely used in India, and performance of these RDTs are affected by deleted Pfhrp2/3 gene in Plasmodium falciparum. This study was planned to confirm Pfhrp2/3 gene deletion incidences and genetic variation in PfHRP2-based RDT positive with P.falciparum malaria cases from India. METHODOLOGY Confirmed positive samples by PfHRP2-based RDTs as P. falciparum (n = 240) from six different endemic regions of India were validated by PCR to assure the actual infection. Two hundred forty samples qualified for DNA intactness by single-copy genes were subjected to amplification for the Pfhrp2/3 gene and its neighbouring gene (downstream and upstream) by PCR genotyping. Genetic variation in samples was analysed post-sequencing using Mega X software. Statistical analysis was performed to validate the genetic variation using Mann-Whitney Test. RESULTS RDT target region of Pfhrp2 gene (exon2) was found deleted in a single sample with presence of the Pfhrp3 exon2. Complete gene deletion of 4.2% was observed in the Pfhrp3 gene. Partial gene deletion was recorded for both pfhrp2 gene (exon2-0.4%, upstream 25.8% and downstream -9.1%) and Pfhrp3 gene (exon2-18.75%, upstream - 22.08% and downstream 13.3%). Eleven new unique types of amino acid repeat sequence and earlier reported amino acid repeat type was found in the Pfhrp2 gene, prompting high genetic variation. CONCLUSIONS This study suggests that parasites lacking Pfhrp2/3 gene and its neighbouring gene (downstream and upstream) are present in malaria endemic areas of India, resulting in false positive results by RDT. Systematic countrywide monitoring for malaria control and elimination of malaria is warranted in this regard.
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Affiliation(s)
- Ms Sarita Kumari
- National Institute of Malaria Research (ICMR), Sector - 8, Dwarka, New Delhi 110077, India; Kumaun University, Sleepy Hallow, Nainital, Uttarakhand 263001, India
| | - Supriya Sharma
- National Institute of Malaria Research (ICMR), Sector - 8, Dwarka, New Delhi 110077, India.
| | - Nitin Bhardwaj
- National Institute of Malaria Research (ICMR), Sector - 8, Dwarka, New Delhi 110077, India; Kumaun University, Sleepy Hallow, Nainital, Uttarakhand 263001, India
| | - Sandeep Kumar
- National Institute of Malaria Research (ICMR), Sector - 8, Dwarka, New Delhi 110077, India; Kumaun University, Sleepy Hallow, Nainital, Uttarakhand 263001, India
| | - Md Zohaib Ahmed
- National Institute of Malaria Research (ICMR), Sector - 8, Dwarka, New Delhi 110077, India; Kumaun University, Sleepy Hallow, Nainital, Uttarakhand 263001, India
| | - Veena Pande
- Kumaun University, Sleepy Hallow, Nainital, Uttarakhand 263001, India
| | - Anupkumar R Anvikar
- National Institute of Malaria Research (ICMR), Sector - 8, Dwarka, New Delhi 110077, India.
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27
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Hosch S, Yoboue CA, Donfack OT, Guirou EA, Dangy JP, Mpina M, Nyakurungu E, Blöchliger K, Guerra CA, Phiri WP, Ayekaba MO, García GA, Tanner M, Daubenberger C, Schindler T. Analysis of nucleic acids extracted from rapid diagnostic tests reveals a significant proportion of false positive test results associated with recent malaria treatment. Malar J 2022; 21:23. [PMID: 35073934 PMCID: PMC8785039 DOI: 10.1186/s12936-022-04043-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 01/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Surveillance programmes often use malaria rapid diagnostic tests (RDTs) to determine the proportion of the population carrying parasites in their peripheral blood to assess the malaria transmission intensity. Despite an increasing number of reports on false-negative and false-positive RDT results, there is a lack of systematic quality control activities for RDTs deployed in malaria surveillance programmes. METHODS The diagnostic performance of field-deployed RDTs used for malaria surveys was assessed by retrospective molecular analysis of the blood retained on the tests. RESULTS Of the 2865 RDTs that were collected in 2018 on Bioko Island and analysed in this study, 4.7% had a false-negative result. These false-negative RDTs were associated with low parasite density infections. In 16.6% of analysed samples, masked pfhrp2 and pfhrp3 gene deletions were identified, in which at least one Plasmodium falciparum strain carried a gene deletion. Among all positive RDTs analysed, 28.4% were tested negative by qPCR and therefore considered to be false-positive. Analysing the questionnaire data collected from the participants, this high proportion of false-positive RDTs could be explained by P. falciparum histidine rich protein 2 (PfHRP2) antigen persistence after recent malaria treatment. CONCLUSION Malaria surveillance depending solely on RDTs needs well-integrated quality control procedures to assess the extent and impact of reduced sensitivity and specificity of RDTs on malaria control programmes.
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Affiliation(s)
- Salome Hosch
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Charlene Aya Yoboue
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | | | - Etienne A Guirou
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Maxmillian Mpina
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,Ifakara Health Institute, Bagamoyo, United Republic of Tanzania.,Laboratorio de Investigaciones de Baney, Baney, Equatorial Guinea
| | - Elizabeth Nyakurungu
- Ifakara Health Institute, Bagamoyo, United Republic of Tanzania.,Laboratorio de Investigaciones de Baney, Baney, Equatorial Guinea
| | - Koranan Blöchliger
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Carlos A Guerra
- Medical Care Development International, Malabo, Equatorial Guinea
| | - Wonder P Phiri
- Medical Care Development International, Malabo, Equatorial Guinea
| | | | | | - Marcel Tanner
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Claudia Daubenberger
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Tobias Schindler
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland. .,Laboratorio de Investigaciones de Baney, Baney, Equatorial Guinea.
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28
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Gilchrist JJ, Kariuki SN, Watson JA, Band G, Uyoga S, Ndila CM, Mturi N, Mwarumba S, Mohammed S, Mosobo M, Alasoo K, Rockett KA, Mentzer AJ, Kwiatkowski DP, Hill AVS, Maitland K, Scott JAG, Williams TN. BIRC6 modifies risk of invasive bacterial infection in Kenyan children. eLife 2022; 11:77461. [PMID: 35866869 PMCID: PMC9391038 DOI: 10.7554/elife.77461] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/22/2022] [Indexed: 11/23/2022] Open
Abstract
Invasive bacterial disease is a major cause of morbidity and mortality in African children. Despite being caused by diverse pathogens, children with sepsis are clinically indistinguishable from one another. In spite of this, most genetic susceptibility loci for invasive infection that have been discovered to date are pathogen specific and are not therefore suggestive of a shared genetic architecture of bacterial sepsis. Here, we utilise probabilistic diagnostic models to identify children with a high probability of invasive bacterial disease among critically unwell Kenyan children with Plasmodium falciparum parasitaemia. We construct a joint dataset including 1445 bacteraemia cases and 1143 severe malaria cases, and population controls, among critically unwell Kenyan children that have previously been genotyped for human genetic variation. Using these data, we perform a cross-trait genome-wide association study of invasive bacterial infection, weighting cases according to their probability of bacterial disease. In doing so, we identify and validate a novel risk locus for invasive infection secondary to multiple bacterial pathogens, that has no apparent effect on malaria risk. The locus identified modifies splicing of BIRC6 in stimulated monocytes, implicating regulation of apoptosis and autophagy in the pathogenesis of sepsis in Kenyan children.
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Affiliation(s)
- James J Gilchrist
- Department of Paediatrics, University of OxfordOxfordUnited Kingdom,MRC–Weatherall Institute of Molecular Medicine, University of OxfordOxfordUnited Kingdom,Wellcome Centre for Human Genetics, University of OxfordOxfordUnited Kingdom
| | - Silvia N Kariuki
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - James A Watson
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom,Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol UniversityBangkokThailand
| | - Gavin Band
- Wellcome Centre for Human Genetics, University of OxfordOxfordUnited Kingdom
| | - Sophie Uyoga
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - Carolyne M Ndila
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - Neema Mturi
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - Salim Mwarumba
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - Shebe Mohammed
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - Moses Mosobo
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya
| | - Kaur Alasoo
- Institute of Computer Science, University of TartuTartuEstonia
| | - Kirk A Rockett
- Wellcome Centre for Human Genetics, University of OxfordOxfordUnited Kingdom
| | - Alexander J Mentzer
- Wellcome Centre for Human Genetics, University of OxfordOxfordUnited Kingdom
| | - Dominic P Kwiatkowski
- Wellcome Centre for Human Genetics, University of OxfordOxfordUnited Kingdom,Wellcome Sanger InstituteCambridgeUnited Kingdom
| | - Adrian VS Hill
- Wellcome Centre for Human Genetics, University of OxfordOxfordUnited Kingdom,The Jenner Institute, University of OxfordOxfordUnited Kingdom
| | - Kathryn Maitland
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya,Division of Medicine, Imperial CollegeLondonUnited Kingdom
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya,Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical MedicineLondonUnited Kingdom
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-CoastKilifiKenya,Institute for Global Health Innovation, Department of Surgery and Cancer, Imperial CollegeLondonUnited Kingdom
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Aggarwal S, Peng WK, Srivastava S. Multi-Omics Advancements towards Plasmodium vivax Malaria Diagnosis. Diagnostics (Basel) 2021; 11:2222. [PMID: 34943459 PMCID: PMC8700291 DOI: 10.3390/diagnostics11122222] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/21/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Plasmodium vivax malaria is one of the most lethal infectious diseases, with 7 million infections annually. One of the roadblocks to global malaria elimination is the lack of highly sensitive, specific, and accurate diagnostic tools. The absence of diagnostic tools in particular has led to poor differentiation among parasite species, poor prognosis, and delayed treatment. The improvement necessary in diagnostic tools can be broadly grouped into two categories: technologies-driven and omics-driven progress over time. This article discusses the recent advancement in omics-based malaria for identifying the next generation biomarkers for a highly sensitive and specific assay with a rapid and antecedent prognosis of the disease. We summarize the state-of-the-art diagnostic technologies, the key challenges, opportunities, and emerging prospects of multi-omics-based sensors.
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Affiliation(s)
- Shalini Aggarwal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India;
| | - Weng Kung Peng
- Songshan Lake Materials Laboratory, Building A1, University Innovation Park, Dongguan 523808, China
- Precision Medicine-Engineering Group, International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal
| | - Sanjeeva Srivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India;
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30
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Yerlikaya S, Owusu EDA, Frimpong A, DeLisle RK, Ding XC. A Dual, Systematic Approach to Malaria Diagnostic Biomarker Discovery. Clin Infect Dis 2021; 74:40-51. [PMID: 34718455 PMCID: PMC8752250 DOI: 10.1093/cid/ciab251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Indexed: 11/15/2022] Open
Abstract
Background The emergence and spread of Plasmodium falciparum parasites that lack HRP2/3 proteins and the resulting decreased utility of HRP2-based malaria rapid diagnostic tests (RDTs) prompted the World Health Organization and other global health stakeholders to prioritize the discovery of novel diagnostic biomarkers for malaria. Methods To address this pressing need, we adopted a dual, systematic approach by conducting a systematic review of the literature for publications on diagnostic biomarkers for uncomplicated malaria and a systematic in silico analysis of P. falciparum proteomics data for Plasmodium proteins with favorable diagnostic features. Results Our complementary analyses led us to 2 novel malaria diagnostic biomarkers compatible for use in an RDT format: glyceraldehyde 3-phosphate dehydrogenase and dihydrofolate reductase-thymidylate synthase. Conclusions Overall, our results pave the way for the development of next-generation malaria RDTs based on new antigens by identifying 2 lead candidates with favorable diagnostic features and partially de-risked product development prospects.
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Affiliation(s)
- Seda Yerlikaya
- Foundation for Innovative New Diagnostics, Geneva, Switzerland
| | - Ewurama D A Owusu
- Foundation for Innovative New Diagnostics, Geneva, Switzerland.,Department of Medical Laboratory Sciences, School of Biomedical and Allied Health Sciences, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Augustina Frimpong
- West Africa Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Accra, Ghana.,Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana.,African Institute for Mathematical Sciences, Accra, Ghana
| | | | - Xavier C Ding
- Foundation for Innovative New Diagnostics, Geneva, Switzerland
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31
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Molina-de la Fuente I, Pastor A, Herrador Z, Benito A, Berzosa P. Impact of Plasmodium falciparum pfhrp2 and pfhrp3 gene deletions on malaria control worldwide: a systematic review and meta-analysis. Malar J 2021; 20:276. [PMID: 34158065 PMCID: PMC8220794 DOI: 10.1186/s12936-021-03812-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 06/11/2021] [Indexed: 12/15/2022] Open
Abstract
Background Deletion of pfhrp2 and/or pfhrp3 genes cause false negatives in malaria rapid diagnostic test (RDT) and threating malaria control strategies. This systematic review aims to assess the main methodological aspects in the study of pfhrp2 and pfhrp3 gene deletions and its global epidemiological status, with special focus on their distribution in Africa; and its possible impact in RDT. Methods The systematic review was conducted by examining the principal issues of study design and methodological workflow of studies addressing pfhrp2 deletion. Meta-analysis was applied to represent reported prevalences of pfhrp2 and pfhrp3 single and double deletion in the World Health Organization (WHO) region. Pooled-prevalence of deletions was calculated using DerSimonnian-Laird random effect model. Then, in-deep analysis focused on Africa was performed to assess possible variables related with these deletions. Finally, the impact of these deletions in RDT results was analysed combining reported information about RDT sensitivity and deletion prevalences. Results 49 articles were included for the systematic review and 37 for the meta-analysis, 13 of them placed in Africa. Study design differs significantly, especially in terms of population sample and information reported, resulting in high heterogeneity between studies that difficulties comparisons and merged conclusions. Reported prevalences vary widely in all the WHO regions, significantly higher deletion were reported in South-Central America, following by Africa and Asia. Pfhrp3 deletion is more prevalent (43% in South-Central America; 3% in Africa; and 1% in Asia) than pfhrp2 deletion (18% in South-Central America; 4% in Africa; and 3% in Asia) worldwide. In Africa, there were not found differences in deletion prevalence by geographical or population origin of samples. The prevalence of deletion among false negatives ranged from 0 to 100% in Africa, but in Asia and South-Central America was only up to 90% and 48%, respectively, showing substantial relation between deletions and false negatives. Conclusion The concerning prevalence of pfhrp2, pfhrp3 and pfhrp2/3 gene deletions, as its possible implications in malaria control, highlights the importance of regular and systematic surveillance of these deletions. This review has also outlined that a standardized methodology could play a key role to ensure comparability between studies to get global conclusions. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03812-0.
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Affiliation(s)
- Irene Molina-de la Fuente
- Department of Biomedicine and Biotechnology, School of Pharmacy, University of Alcalá, Alcalá de Henares, Madrid, Spain. .,Malaria and Neglected Diseases Laboratory, National Centre of Tropical Medicine, Institute of Health Carlos III, 28029, Madrid, Spain. .,Public Health and Epidemiology Research Group, School of Medicine, University of Alcalá, 28871, Alcalá de Henares, Madrid, Spain.
| | - Andrea Pastor
- Public Health and Epidemiology Research Group, School of Medicine, University of Alcalá, 28871, Alcalá de Henares, Madrid, Spain
| | - Zaida Herrador
- National Centre of Epidemiology, Institute of Health Carlos III, 28029, Madrid, Spain.,Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
| | - Agustín Benito
- Malaria and Neglected Diseases Laboratory, National Centre of Tropical Medicine, Institute of Health Carlos III, 28029, Madrid, Spain.,Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
| | - Pedro Berzosa
- Malaria and Neglected Diseases Laboratory, National Centre of Tropical Medicine, Institute of Health Carlos III, 28029, Madrid, Spain.,Network Biomedical Research on Tropical Diseases (RICET in Spanish), Madrid, Spain
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Prosser C, Gresty K, Ellis J, Meyer W, Anderson K, Lee R, Cheng Q. Plasmodium falciparum Histidine-Rich Protein 2 and 3 Gene Deletions in Strains from Nigeria, Sudan, and South Sudan. Emerg Infect Dis 2021; 27:471-479. [PMID: 33496220 PMCID: PMC7853540 DOI: 10.3201/eid2702.191410] [Citation(s) in RCA: 19] [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: 12/18/2022] Open
Abstract
Deletion of histidine-rich protein genes pfhrp2/3 in Plasmodium falciparum causes infections to go undetected by HRP2-based malaria rapid diagnostic tests. We analyzed P. falciparum malaria cases imported to Australia (n = 210, collected 2010–2018) for their pfhrp2/3 status. We detected gene deletions in patients from 12 of 25 countries. We found >10% pfhrp2-deletion levels in those from Nigeria (13.3%, n = 30), Sudan (11.2%, n = 39), and South Sudan (17.7%, n = 17) and low levels of pfhrp3 deletion from Sudan (3.6%) and South Sudan (5.9%). No parasites with pfhrp2/3 double deletions were detected. Microsatellite typing of parasites from Nigeria, Sudan, and South Sudan revealed low relatedness among gene-deleted parasites, indicating independent emergences. The gene deletion proportions signify a risk of false-negative HRP2-RDT results. This study’s findings warrant surveillance to determine whether the prevalence of gene-deleted parasites justifies switching malaria rapid diagnostic tests in Nigeria, Sudan, and South Sudan.
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Agaba BB, Anderson K, Gresty K, Prosser C, Smith D, Nankabirwa JI, Nsobya S, Yeka A, Namubiru R, Arinaitwe E, Mbaka P, Kissa J, Lim CS, Karamagi C, Nakayaga JK, Kamya MR, Cheng Q. Genetic diversity and genetic relatedness in Plasmodium falciparum parasite population in individuals with uncomplicated malaria based on microsatellite typing in Eastern and Western regions of Uganda, 2019-2020. Malar J 2021; 20:242. [PMID: 34059047 PMCID: PMC8165787 DOI: 10.1186/s12936-021-03763-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/11/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Genetic diversity and parasite relatedness are essential parameters for assessing impact of interventions and understanding transmission dynamics of malaria parasites, however data on its status in Plasmodium falciparum populations in Uganda is limited. Microsatellite markers and DNA sequencing were used to determine diversity and molecular characterization of P. falciparum parasite populations in Uganda. METHODS A total of 147 P. falciparum genomic DNA samples collected from cross-sectional surveys in symptomatic individuals of 2-10 years were characterized by genotyping of seven highly polymorphic neutral microsatellite markers (n = 85) and genetic sequencing of the Histidine Rich Protein 2 (pfhrp2) gene (n = 62). ArcGIS was used to map the geographical distribution of isolates while statistical testing was done using Student's t-test or Wilcoxon's rank-sum test and Fisher's exact test as appropriate at P ≤ 0.05. RESULTS Overall, 75.5% (95% CI 61.1-85.8) and 24.5% (95% CI14.2-38.9) of parasites examined were of multiclonal (mixed genotype) and single clone infections, respectively. Multiclonal infections occurred more frequently in the Eastern region 73.7% (95% CI 48.8-89.1), P < 0.05. Overall, multiplicity of infection (MOI) was 1.9 (95% CI 1.7-2.1), P = 0.01 that was similar between age groups (1.8 vs 1.9), P = 0.60 and regions (1.9 vs 1.8), P = 0.43 for the < 5 and ≥ 5 years and Eastern and Western regions, respectively. Genomic sequencing of the pfhrp2 exon2 revealed a high level of genetic diversity reflected in 96.8% (60/62) unique sequence types. Repeat type AHHAAAHHATD and HRP2 sequence Type C were more frequent in RDT-/PCR + samples (1.9% vs 1.5%) and (13% vs 8%), P < 0.05 respectively. Genetic relatedness analysis revealed small clusters of gene deleted parasites in Uganda, but no clustering with Eritrean parasites. CONCLUSION High level of genetic diversity of P. falciparum parasites reflected in the frequency of multiclonal infections, multiplicity of infection and variability of the pfhrp2 gene observed in this study is consistent with the high malaria transmission intensity in these settings. Parasite genetic analysis suggested spontaneous emergence and clonal expansion of pfhrp2 deleted parasites that require close monitoring to inform national malaria diagnosis and case management policies.
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Affiliation(s)
- Bosco B Agaba
- College of Health Sciences, Makerere University, Kampala, Uganda. .,National Malaria Control Division, Kampala, Uganda.
| | - Karen Anderson
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Karryn Gresty
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Christiane Prosser
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - David Smith
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Joaniter I Nankabirwa
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Sam Nsobya
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Adoke Yeka
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Rhoda Namubiru
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | - Paul Mbaka
- World Health Organization Country Office, Kampala, Uganda
| | - John Kissa
- National Health Information Division, Ministry of Health, Kampala, Uganda
| | - Chae Seung Lim
- Department of Laboratory Medicine, College of Health Sciences, Korea University, Seoul, South Korea
| | - Charles Karamagi
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Joan K Nakayaga
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Moses R Kamya
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Qin Cheng
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
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King M, George AE, Cisteró P, Tarr-Attia CK, Arregui B, Omeonga S, Chen H, Meyer García-Sípido A, Sarukhan A, Bassat Q, Lansana DP, Mayor A. No evidence of false-negative Plasmodium falciparum rapid diagnostic results in Monrovia, Liberia. Malar J 2021; 20:238. [PMID: 34039355 PMCID: PMC8157453 DOI: 10.1186/s12936-021-03774-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/16/2021] [Indexed: 11/25/2022] Open
Abstract
Background Malaria diagnosis in many malaria-endemic countries relies mainly on the use of rapid diagnostic tests (RDTs). The majority of commercial RDTs used in Africa detect the Plasmodium falciparum histidine-rich protein 2 (PfHRP2). pfhrp2/3 gene deletions can therefore lead to false-negative RDT results. This study aimed to evaluate the frequency of PCR-confirmed, false-negative P. falciparum RDT results in Monrovia, Liberia. Methods PfHRP2-based RDT (Paracheck Pf®) and microscopy results from 1038 individuals with fever or history of fever (n = 951) and pregnant women at first antenatal care (ANC) visit (n = 87) enrolled in the Saint Joseph’s Catholic Hospital (Monrovia) from March to July 2019 were used to assess the frequency of false-negative RDT results. True–false negatives were confirmed by detecting the presence of P. falciparum DNA by quantitative PCR in samples from individuals with discrepant RDT and microscopy results. Samples that were positive by 18S rRNA qPCR but negative by PfHRP2-RDT were subjected to multiplex qPCR assay for detection of pfhrp2 and pfhrp3. Results One-hundred and eighty-six (19.6%) and 200 (21.0%) of the 951 febrile participants had a P. falciparum-positive result by RDT and microscopy, respectively. Positivity rate increased with age and the reporting of joint pain, chills and shivers, vomiting and weakness, and decreased with the presence of coughs and nausea. The positivity rate at first ANC visit was 5.7% (n = 5) and 8% (n = 7) by RDT and microscopy, respectively. Out of 207 Plasmodium infections detected by microscopy, 22 (11%) were negative by RDT. qPCR confirmed absence of P. falciparum DNA in the 16 RDT-negative but microscopy-positive samples which were available for molecular testing. Among the 14 samples that were positive by qPCR but negative by RDT and microscopy, 3 only amplified pfldh, and among these 3 all were positive for pfhrp2 and pfhrp3. Conclusion There is no qPCR-confirmed evidence of false-negative RDT results due to pfhrp2/pfhrp3 deletions in this study conducted in Monrovia (Liberia). This indicates that these deletions are not expected to affect the performance of PfHRP2-based RDTs for the diagnosis of malaria in Liberia. Nevertheless, active surveillance for the emergence of PfHRP2 deletions is required.
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Affiliation(s)
- Mandella King
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo, Town, PO Box 10512, 1100, Monrovia, Liberia
| | - Alexander E George
- Liberia Medicines & Health Products Regulatory Authority, VP Road, Old Road, Sinkor , PO Box 1994, Monrovia, Liberia
| | - Pau Cisteró
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain
| | - Christine K Tarr-Attia
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo, Town, PO Box 10512, 1100, Monrovia, Liberia
| | - Beatriz Arregui
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain
| | - Senga Omeonga
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo, Town, PO Box 10512, 1100, Monrovia, Liberia
| | - Haily Chen
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain
| | | | - Adelaida Sarukhan
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain
| | - Quique Bassat
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.,Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.,ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain.,Pediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Esplugues,, Barcelona, Spain
| | - Dawoh Peter Lansana
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo, Town, PO Box 10512, 1100, Monrovia, Liberia
| | - Alfredo Mayor
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic - Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain. .,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique. .,Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
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Mahittikorn A, Masangkay FR, Kotepui KU, De Jesus Milanez G, Kotepui M. Comparative performance of PCR using DNA extracted from dried blood spots and whole blood samples for malaria diagnosis: a meta-analysis. Sci Rep 2021; 11:4845. [PMID: 33649410 PMCID: PMC7921648 DOI: 10.1038/s41598-021-83977-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/10/2021] [Indexed: 11/24/2022] Open
Abstract
Polymerase chain reaction (PCR) using deoxyribonucleic acid (DNA) extracted from dried blood spots (DBS) provides a fast, inexpensive, and convenient method for large-scale epidemiological studies. This study compared the performance of PCR between DNA extracted from DBS and DNA obtained from whole blood for detecting malarial parasites. Primary studies assessing the diagnostic performance of PCR using DNA extracted from DBS and whole blood for detecting malarial parasites were obtained from the ISI Web of Science, Scopus, and PubMed databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were plotted in forest plots using Review Manager version 5.3. Statistical analysis was performed via random-effects meta-analysis. Data heterogeneity was assessed using the I2 statistic. Of the 904 studies retrieved from the databases, seven were included in this study. The pooled meta-analysis demonstrated no significant difference in the comparative performance of PCR for detecting malaria parasites between DNA extracted from DBS and that extracted from whole blood (OR 0.85; 95% CI 0.62–1.16; I2 = 78%). However, subgroup analysis demonstrated that PCR using DNA extracted from DBS was less accurate in detecting Plasmodium vivax than that using DNA extracted from whole blood (OR = 0.85; 95% CI 0.77–0.94). In conclusion, a significant difference in detecting P. vivax was observed between PCR using DNA extracted from DBS and that using DNA extracted from whole blood. Therefore, P. vivax in endemic areas should be identified and detected with care with PCR using DNA obtained from DBS which potentially leads to a negative result. Further studies are required to investigate the performance of PCR using DBS for detecting P. vivax and other malarial parasites to provide data in research and routine surveillance of malaria, especially with renewed efforts towards the eradication of the disease.
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Affiliation(s)
- Aongart Mahittikorn
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Frederick Ramirez Masangkay
- Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University-Manila, Manila, Philippines
| | - Kwuntida Uthaisar Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Giovanni De Jesus Milanez
- Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University-Manila, Manila, Philippines
| | - Manas Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand.
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Alemayehu GS, Blackburn K, Lopez K, Cambel Dieng C, Lo E, Janies D, Golassa L. Detection of high prevalence of Plasmodium falciparum histidine-rich protein 2/3 gene deletions in Assosa zone, Ethiopia: implication for malaria diagnosis. Malar J 2021; 20:109. [PMID: 33622309 PMCID: PMC8095343 DOI: 10.1186/s12936-021-03629-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 02/06/2021] [Indexed: 11/10/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) targeting histidine rich protein 2(HRP2) are widely used for diagnosis of Plasmodium falciparum infections. Besides PfHRP2, the PfHRP3 antigen contributes to the detection of P. falciparum infections in PfHRP2 RDTs. However, the performance HRP2-based RDT is affected by pfhrp2/3 gene deletions resulting in false-negative test results. The objective of this study was to determine the presence and prevalence of pfhrp2/3 gene deletions including the respective flanking regions among symptomatic patients in Assosa zone, Northwest Ethiopia. Methods A health-facility based cross-sectional study was conducted in febrile patients seeking a malaria diagnosis in 2018. Blood samples were collected by finger-prick for microscopic examination of blood smears, malaria RDT, and molecular analysis using dried blood spots (DBS) prepared on Whatman filter paper. A total of 218 P. falciparum positive samples confirmed by quantitative PCR were included for molecular assay of pfhrp2/3 target gene. Results Of 218 P. falciparum positive samples, exon 2 deletions were observed in 17.9% of pfhrp2 gene and in 9.2% of pfhrp3 gene. A high proportion of deletions in short segments of pfhrp2 exon1-2 (50%) was also detected while the deletions of the pfhrp3 exon1-2 gene were 4.1%. The deletions were extended to the downstream and upstream of the flanking regions in pfhrp2/3 gene (above 30%). Of eighty-six PfHRP2 RDT negative samples, thirty-six lacked pfhrp2 exon 2. Five PfHRP2 RDT negative samples had double deletions in pfhrp2 exon 2 and pfhrp3 exon2. Of these double deletions, only two of the samples with a parasite density above 2000 parasite/µl were positive by the microscopy. Three samples with intact pfhrp3 exon2 in the pfhrp2 exon2 deleted parasite isolates were found to be positive by PfHRP2 RDT and microscopy with a parasite density above 10,000/µl. Conclusion This study confirms the presence of deletions of pfhrp2/3 gene including the flanking regions. Pfhrp2/3 gene deletions results in false-negative results undoubtedly affect the current malaria control and elimination effort in the country. However, further countrywide investigations are required to determine the magnitude of pfhrp2/3 gene deletions and its consequences on routine malaria diagnosis.
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Affiliation(s)
| | - Kayla Blackburn
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Karen Lopez
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Cheikh Cambel Dieng
- Department of Biological Sciences, Charlotte, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Eugenia Lo
- Department of Biological Sciences, Charlotte, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Daniel Janies
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Lemu Golassa
- Addis Ababa University, Aklilu Lemma Institute of Pathobiology, Addis Ababa, Ethiopia
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Mudare N, Matsena-Zingoni Z, Makuwaza A, Mamini E, Munyati SS, Gwanzura L, Midzi N, Mutambu SL, Mason P, Kobayashi T, Mharakurwa S. Detecting Plasmodium falciparum in community surveys: a comparison of Paracheck Pf® Test and ICT Malaria Pf® Cassette Test to polymerase chain reaction in Mutasa District, Zimbabwe. Malar J 2021; 20:14. [PMID: 33407488 PMCID: PMC7789522 DOI: 10.1186/s12936-020-03536-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/07/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Microscopy and rapid diagnostic tests (RDTs) are the main techniques used to diagnose malaria. While microscopy is considered the gold standard, RDTs have established popularity as they allow for rapid diagnosis with minimal technical skills. This study aimed to compare the diagnostic performance of two Plasmodium falciparum histidine-rich protein 2 (PfHRP2)-based RDTs (Paracheck Pf® Test (Paracheck) and Malaria Pf™ ICT (ICT)) to polymerase chain reaction (PCR) in a community survey. METHODS A cross-sectional study was conducted between October 2012 and December 2014 in Mutasa District, Manicaland Province, eastern Zimbabwe. Households were randomly selected using satellite imagery, and 224 households were visited. Residents present in the household on the date of the visit were recruited for the study. Participants of all age groups from the selected households were screened with Paracheck and ICT RDTs in parallel. Dried blood spots (DBS) and thin and thick smears were collected. Parasite DNA extracted from the DBS was subjected to nested PCR targeting the Plasmodium cytochrome b mitochondrial gene. Data analysis was performed using the Cohen's Kappa test to determine the interrater agreement and the sensitivity and specificity of the diagnostic test were reported. RESULTS Results from a total of 702 participants were analysed. Most were females, 397 (57%), and the median age of participants was 21 years with an interquartile range of 9-39 years. Of those who were screened, 8 (1.1%), 35 (5.0%), and 21 (2.9%) were malaria parasite positive by microscopy, RDT and PCR, respectively. Paracheck and ICT RDTs had a 100% agreement. Comparing RDT and PCR results, 34 participants (4.8%) had discordant results. Most of the discordant cases were RDT positive but PCR negative (n = 24). Half of those RDT positive, but PCR negative individuals reported anti-malarials to use in the past month, which is significantly higher than reported anti-malarial drug use in the population (p < 0.001). The participant was febrile on the day of the visit, but relying on PfHRP2-based RDT would miss this case. Among the diagnostic methods evaluated, with reference to PCR, the sensitivity was higher with the RDT (52.4%) while specificity was higher with the microscopy (99.9%). The positive predictive value (PPV) was higher with the microscopy (87.5%), while the negative predictive values were similar for both microscopy and RDTs (98%). Overall, a strong correlated agreement with PCR was observed for the microscopy (97.9%) and the RDTs (95.2%). CONCLUSIONS Paracheck and ICT RDTs showed 100% agreement and can be used interchangeably. As malaria transmission declines and Zimbabwe aims to reach malaria elimination, management of infected individuals with low parasitaemia as well as non-P. falciparum infection can be critical.
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Affiliation(s)
| | | | | | - Edmore Mamini
- Biomedical Research and Training Institute, Harare, Zimbabwe
| | | | - Lovemore Gwanzura
- Biomedical Research and Training Institute, Harare, Zimbabwe.,University of Zimbabwe, College of Health Sciences, Institute of Continuing Health Education, Harare, Zimbabwe
| | | | | | - Peter Mason
- Biomedical Research and Training Institute, Harare, Zimbabwe
| | - Tamaki Kobayashi
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sungano Mharakurwa
- Africa University, Mutare, Zimbabwe. .,Biomedical Research and Training Institute, Harare, Zimbabwe.
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Bosco AB, Nankabirwa JI, Yeka A, Nsobya S, Gresty K, Anderson K, Mbaka P, Prosser C, Smith D, Opigo J, Namubiru R, Arinaitwe E, Kissa J, Gonahasa S, Won S, Lee B, Lim CS, Karamagi C, Cheng Q, Nakayaga JK, Kamya MR. Limitations of rapid diagnostic tests in malaria surveys in areas with varied transmission intensity in Uganda 2017-2019: Implications for selection and use of HRP2 RDTs. PLoS One 2020; 15:e0244457. [PMID: 33382787 PMCID: PMC7774953 DOI: 10.1371/journal.pone.0244457] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/09/2020] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Plasmodium falciparum histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDTs) are exclusively recommended for malaria diagnosis in Uganda; however, their functionality can be affected by parasite-related factors that have not been investigated in field settings. METHODS Using a cross-sectional design, we analysed 219 RDT-/microscopy+ and 140 RDT+/microscopy+ dried blood spots obtained from symptomatic children aged 2-10 years from 48 districts in Uganda between 2017 and 2019. We aimed to investigate parasite-related factors contributing to false RDT results by molecular characterization of parasite isolates. ArcGIS software was used to map the geographical distribution of parasites. Statistical analysis was performed using chi-square or Fisher's exact tests, with P ≤ 0.05 indicating significance. Odds ratios (ORs) were used to assess associations, while logistic regression was performed to explore possible factors associated with false RDT results. RESULTS The presence of parasite DNA was confirmed in 92.5% (332/359) of the blood samples. The levels of agreement between the HRP2 RDT and PCR assay results in the (RDT+/microscopy+) and (RDT-/microscopy+) sample subsets were 97.8% (137/140) and 10.9% (24/219), respectively. Factors associated with false-negative RDT results in the (RDT-/microscopy+) samples were parasite density (<1,000/μl), pfhrp2/3 gene deletion and non-P. falciparum species (aOR 2.65, 95% CI: 1.62-4.38, P = 0.001; aOR 4.4, 95% CI 1.72-13.66, P = 0.004; and aOR 18.65, 95% CI: 5.3-38.7, P = 0.001, respectively). Overall, gene deletion and non-P. falciparum species contributed to 12.3% (24/195) and 19.0% (37/195) of false-negative RDT results, respectively. Of the false-negative RDTs results, 80.0% (156/195) were from subjects with low-density infections (< 25 parasites per 200 WBCs or <1,000/μl). CONCLUSION This is the first evaluation and report of the contributions of pfhrp2/3 gene deletion, non-P. falciparum species, and low-density infections to false-negative RDT results under field conditions in Uganda. In view of these findings, the use of HRP2 RDTs should be reconsidered; possibly, switching to combination RDTs that target alternative antigens, particularly in affected areas, may be beneficial. Future evaluations should consider larger and more representative surveys covering other regions of Uganda.
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Affiliation(s)
- Agaba B. Bosco
- College of Health Sciences, Makerere University, Kampala, Uganda
- National Malaria Control Division, Kampala, Uganda
| | - Joaniter I. Nankabirwa
- College of Health Sciences, Makerere University, Kampala, Uganda
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Adoke Yeka
- College of Health Sciences, Makerere University, Kampala, Uganda
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Sam Nsobya
- College of Health Sciences, Makerere University, Kampala, Uganda
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Karryn Gresty
- Australian Defence Force Malaria and Infectious Disease Institute, Queensland, Australia
- The Army Malaria Institute Laboratory, QIMR Berghofer Medical Research Institute, Kampala, Uganda
| | - Karen Anderson
- Australian Defence Force Malaria and Infectious Disease Institute, Queensland, Australia
- The Army Malaria Institute Laboratory, QIMR Berghofer Medical Research Institute, Kampala, Uganda
| | - Paul Mbaka
- World Health Organization Country Office, Kampala, Uganda
| | - Christiane Prosser
- Australian Defence Force Malaria and Infectious Disease Institute, Queensland, Australia
| | - David Smith
- Australian Defence Force Malaria and Infectious Disease Institute, Queensland, Australia
- The Army Malaria Institute Laboratory, QIMR Berghofer Medical Research Institute, Kampala, Uganda
| | - Jimmy Opigo
- National Malaria Control Division, Kampala, Uganda
| | - Rhoda Namubiru
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | - John Kissa
- National Health Information Division, Ministry of Health, Kampala, Uganda
| | | | - Sungho Won
- Department of Public Health Sciences, Seoul National University, Seoul, S. Korea
| | - Bora Lee
- Department of Public Health Sciences, Seoul National University, Seoul, S. Korea
| | - Chae Seung Lim
- Department of Laboratory Medicine, College of Health Sciences, Korea University, Seoul, S. Korea
| | - Charles Karamagi
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Qin Cheng
- Australian Defence Force Malaria and Infectious Disease Institute, Queensland, Australia
- The Army Malaria Institute Laboratory, QIMR Berghofer Medical Research Institute, Kampala, Uganda
| | - Joan K. Nakayaga
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Moses R. Kamya
- College of Health Sciences, Makerere University, Kampala, Uganda
- Infectious Diseases Research Collaboration, Kampala, Uganda
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Galatas B, Mayor A, Gupta H, Balanza N, Jang IK, Nhamussua L, Simone W, Cisteró P, Chidimatembue A, Munguambe H, Saúte F, Aide P, Bassat Q. Field performance of ultrasensitive and conventional malaria rapid diagnostic tests in southern Mozambique. Malar J 2020; 19:451. [PMID: 33287822 PMCID: PMC7720469 DOI: 10.1186/s12936-020-03526-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 11/26/2020] [Indexed: 01/01/2023] Open
Abstract
Background An ultrasensitive malaria rapid diagnostic test (RDT) was recently developed for the improved detection of low-density Plasmodium falciparum infections. This study aimed to compare the diagnostic performance of the PfHRP2-based Abbott Malaria Ag P. falciparum ultrasensitive RDT (uRDT) to that of the conventional SD-Bioline Malaria Ag P. falciparum RDT (cRDT) when performed under field conditions. Methods Finger-prick blood samples were collected from adults and children in two cross-sectional surveys in May of 2017 in southern Mozambique. Using real-time quantitative PCR (RT-qPCR) as the reference method, the age-specific diagnostic performance indicators of the cRDT and uRDT were compared. The presence of histidine-rich protein 2 (HRP2) and Plasmodium lactate dehydrogenase (pLDH) antigens was evaluated in a subset from dried blood spots by a quantitative antigen assay. pfhrp2 and pfhrp3 gene deletions were assessed in samples positive by RT-qPCR and negative by both RDTs. Results Among the 4,396 participants with complete test results, the sensitivity of uRDTs (68.2; 95% CI 60.8 to 74.9) was marginally better than that of cRDTs (61.5; 95% CI 53.9 to 68.6) (p-value = 0.004), while the specificities were similar (uRDT: 99.0 [95% CI 98.6 to 99.2], cRDT: 99.2 [95% CI 98.9 to 99.4], p-value = 0.02). While the performance of both RDTs was lowest in ≥ 15-year-olds, driven by the higher prevalence of low parasite density infections in this group, the sensitivity of uRDTs was significantly higher in this age group (54.9, 95% CI 40.3 to 68.9) compared to the sensitivity of cRDTs (39.2, 95% CI 25.8 to 53.9) (p-value = 0.008). Both RDTs detected P. falciparum infections at similar geometric mean parasite densities (112.9 parasites/μL for uRDTs and 145.5 parasites/μL for cRDTs). The presence of HRP2 antigen was similar among false positive (FP) samples of both tests (80.5% among uRDT-FPs and 84.4% among cRDT-FPs). Only one false negative sample was detected with a partial pfhrp2 deletion. Conclusion This study showed that the uRDTs developed by Abbott do not substantially outperform SD-Bioline Pf malaria RDTs in the community and are still not comparable to molecular methods to detect P. falciparum infections in this study setting.
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Affiliation(s)
- Beatriz Galatas
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain. .,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique.
| | - Alfredo Mayor
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Himanshu Gupta
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Núria Balanza
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | | | - Lidia Nhamussua
- Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
| | - Wilson Simone
- Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
| | - Pau Cisteró
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | | | | | - Francisco Saúte
- Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
| | - Pedro Aide
- Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique.,National Institute of Health, Ministry of Health, Maputo, Mozambique
| | - Quique Bassat
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.,ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain.,Pediatric Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu (University of Barcelona), Barcelona, Spain
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40
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Morang'a CM, Amenga-Etego L, Bah SY, Appiah V, Amuzu DSY, Amoako N, Abugri J, Oduro AR, Cunnington AJ, Awandare GA, Otto TD. Machine learning approaches classify clinical malaria outcomes based on haematological parameters. BMC Med 2020; 18:375. [PMID: 33250058 PMCID: PMC7702702 DOI: 10.1186/s12916-020-01823-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/22/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Malaria is still a major global health burden, with more than 3.2 billion people in 91 countries remaining at risk of the disease. Accurately distinguishing malaria from other diseases, especially uncomplicated malaria (UM) from non-malarial infections (nMI), remains a challenge. Furthermore, the success of rapid diagnostic tests (RDTs) is threatened by Pfhrp2/3 deletions and decreased sensitivity at low parasitaemia. Analysis of haematological indices can be used to support the identification of possible malaria cases for further diagnosis, especially in travellers returning from endemic areas. As a new application for precision medicine, we aimed to evaluate machine learning (ML) approaches that can accurately classify nMI, UM, and severe malaria (SM) using haematological parameters. METHODS We obtained haematological data from 2,207 participants collected in Ghana: nMI (n = 978), SM (n = 526), and UM (n = 703). Six different ML approaches were tested, to select the best approach. An artificial neural network (ANN) with three hidden layers was used for multi-classification of UM, SM, and uMI. Binary classifiers were developed to further identify the parameters that can distinguish UM or SM from nMI. Local interpretable model-agnostic explanations (LIME) were used to explain the binary classifiers. RESULTS The multi-classification model had greater than 85% training and testing accuracy to distinguish clinical malaria from nMI. To distinguish UM from nMI, our approach identified platelet counts, red blood cell (RBC) counts, lymphocyte counts, and percentages as the top classifiers of UM with 0.801 test accuracy (AUC = 0.866 and F1 score = 0.747). To distinguish SM from nMI, the classifier had a test accuracy of 0.96 (AUC = 0.983 and F1 score = 0.944) with mean platelet volume and mean cell volume being the unique classifiers of SM. Random forest was used to confirm the classifications, and it showed that platelet and RBC counts were the major classifiers of UM, regardless of possible confounders such as patient age and sampling location. CONCLUSION The study provides proof of concept methods that classify UM and SM from nMI, showing that the ML approach is a feasible tool for clinical decision support. In the future, ML approaches could be incorporated into clinical decision-support algorithms for the diagnosis of acute febrile illness and monitoring response to acute SM treatment particularly in endemic settings.
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Affiliation(s)
- Collins M Morang'a
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Lucas Amenga-Etego
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.
| | - Saikou Y Bah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.,Florey Institute, Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Vincent Appiah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Dominic S Y Amuzu
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Nicholas Amoako
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - James Abugri
- Department of Applied Chemistry and Biochemistry, C. K Tedam University of Technology and Applied Sciences, Navrongo, Ghana
| | - Abraham R Oduro
- Ministry of Health, Navrongo Health Research Centre (NHRC), Navrongo, Ghana
| | - Aubrey J Cunnington
- Section of Pediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Thomas D Otto
- Institute of Infection, Immunity & Inflammation, MVLS, University of Glasgow, Glasgow, UK.
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41
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Aninagyei E. Repeated sampling improved the sensitivity of malaria microscopy in children under six years. BMC Res Notes 2020; 13:508. [PMID: 33148309 PMCID: PMC7640445 DOI: 10.1186/s13104-020-05359-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 10/25/2020] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Microscopy remains the gold standard for identification of malaria parasites. However, the sensitivity of malaria microscopy is low. This study evaluated the impact of repeated sampling up to 12 h in 177 children < 6 years with suspected malaria. RESULTS The median age was 3 years (interquartile range, 2.0-4.0 years). Eighty-nine percent (158/177) presented with hyperthermia together with one or more of the following symptoms: chills, headache, sweating, fatigue, nausea, abdominal pain, vomiting, diarrhea and cough. Baseline microscopy confirmed malaria in 29.9% (53/177) of the suspects. Repeated testing at 6 and 12 h increased the positive detection rates to 35.0% (62/177) and 41.8% (74/177), respectively. Microscopy underestimated malaria diagnosis by 11.9% on single testing. Children showing classical signs of malaria but with initial negative parasitological reports should be retested between 6 to 12 h to confirm or rule out a diagnosis of malaria.
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Affiliation(s)
- Enoch Aninagyei
- Department of Biomedical Sciences, School of Basic and Biomedical Sciences, University of Health and Allied Sciences, PMB 31, Ho, Volta Region, Ghana.
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42
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Bosco AB, Anderson K, Gresty K, Prosser C, Smith D, Nankabirwa JI, Nsobya S, Yeka A, Opigo J, Gonahasa S, Namubiru R, Arinaitwe E, Mbaka P, Kissa J, Won S, Lee B, Lim CS, Karamagi C, Cunningham J, Nakayaga JK, Kamya MR, Cheng Q. Molecular surveillance reveals the presence of pfhrp2 and pfhrp3 gene deletions in Plasmodium falciparum parasite populations in Uganda, 2017-2019. Malar J 2020; 19:300. [PMID: 32843041 PMCID: PMC7449024 DOI: 10.1186/s12936-020-03362-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 08/05/2020] [Indexed: 01/22/2023] Open
Abstract
Background Histidine-rich protein-2 (HRP2)-based rapid diagnostic tests (RDTs) are the only RDTs recommended for malaria diagnosis in Uganda. However, the emergence of Plasmodium falciparum histidine rich protein 2 and 3 (pfhrp2 and pfhrp3) gene deletions threatens their usefulness as malaria diagnostic and surveillance tools. The pfhrp2 and pfhrp3 gene deletions surveillance was conducted in P. falciparum parasite populations in Uganda. Methods Three-hundred (n = 300) P. falciparum isolates collected from cross-sectional malaria surveys in symptomatic individuals in 48 districts of eastern and western Uganda were analysed for the presence of pfhrp2 and pfhrp3 genes. Presence of parasite DNA was confirmed by PCR amplification of the 18s rRNA gene, msp1 and msp2 single copy genes. Presence or absence of deletions was confirmed by amplification of exon1 and exon2 of pfhrp2 and pfhrp3 using gene specific PCR. Results Overall, pfhrp2 and pfhrp3 gene deletions were detected in 29/300 (9.7%, 95% CI 6.6–13.6%) parasite isolates. The pfhrp2 gene was deleted in 10/300 (3.3%, 95% CI 1.6–6.0%) isolates, pfhrp3 in 9/300 (3.0%, 95% CI 1.4–5.6%) while both pfhrp2 and pfhrp3 were deleted in 10/300 (3.3%, 95% CI 1.6–6.0%) parasite isolates. Proportion of pfhrp2/3 deletions was higher in the eastern 14.7% (95% CI 9.7–20.0%) compared to the western region 3.1% (95% CI 0.8–7.7%), p = 0.001. Geographical location was associated with gene deletions aOR 6.25 (2.02–23.55), p = 0.003. Conclusions This is the first large-scale survey reporting the presence of pfhrp2/3 gene deletions in P. falciparum isolates in Uganda. Roll out of RDTs for malaria diagnosis should take into consideration the existence of pfhrp2/3 gene deletions particularly in areas where they were detected. Periodic pfhrp2/3 surveys are recommended to inform future decisions for deployment of alternative RDTs.
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Affiliation(s)
- Agaba B Bosco
- College of Health Sciences, Makerere University, Kampala, Uganda. .,National Malaria Control Division, Kampala, Uganda.
| | - Karen Anderson
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
| | - Karryn Gresty
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
| | - Christiane Prosser
- Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
| | - David Smith
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
| | - Joaniter I Nankabirwa
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Sam Nsobya
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Adoke Yeka
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Jimmy Opigo
- National Malaria Control Division, Kampala, Uganda
| | | | - Rhoda Namubiru
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | - Paul Mbaka
- World Health Organization Country Office, Kampala, Uganda
| | - John Kissa
- National Health Information Division, Ministry of Health, Kampala, Uganda
| | - Sungho Won
- Department of Public Health Sciences, Seoul National University, Seoul, South Korea
| | - Bora Lee
- Department of Public Health Sciences, Seoul National University, Seoul, South Korea
| | - Chae Seung Lim
- Department of Laboratory Medicine, College of Health Sciences, Korea University, Seoul, South Korea
| | - Charles Karamagi
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | - Joan K Nakayaga
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Moses R Kamya
- College of Health Sciences, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Qin Cheng
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
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Kobayashi T. Uncovering hidden pfhrp2/3 deletion Plasmodium falciparum. EBioMedicine 2020; 56:102781. [PMID: 32516741 PMCID: PMC7281805 DOI: 10.1016/j.ebiom.2020.102781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 11/27/2022] Open
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Plasmodium falciparum Histidine-Rich Protein 2 and 3 Gene Deletions and Their Implications in Malaria Control. Diseases 2020; 8:diseases8020015. [PMID: 32443811 PMCID: PMC7349124 DOI: 10.3390/diseases8020015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 04/25/2020] [Accepted: 05/05/2020] [Indexed: 01/15/2023] Open
Abstract
Malaria remains the biggest threat to public health, especially among pregnant women and young children in sub-Saharan Africa. Prompt and accurate diagnosis is critical for effective case management and detection of drug resistance. Conventionally, microscopy and rapid diagnostic tests (RDTs) are the tools of choice for malaria diagnosis. RDTs are simple to use and have been extensively used in the diagnosis of malaria among travelers to malaria-endemic regions, routine case management, and surveillance studies. Most RDTs target the histidine-rich protein (PfHRP) which is exclusively found in Plasmodium falciparum and a metabolic enzyme Plasmodium lactate dehydrogenase (pLDH) which is common among all Plasmodium species. Other RDTs incorporate the enzyme aldolase that is produced by all Plasmodium species. Recently, studies have reported false-negative RDTs primarily due to the deletion of the histidine-rich protein (pfhrp2 and pfhrp3) genes in field isolates of P. falciparum. Herein, we review published literature to establish pfhrp2/pfhrp3 deletions, the extent of these deletions in different geographical regions, and the implication in malaria control. We searched for publications on pfhrp2/pfhrp3 deletions and retrieved all publications that reported on this subject. Overall, 20 publications reported on pfhrp2/pfhrp3 deletions, and most of these studies were done in Central and South America, with very few in Asia and Africa. The few studies in Africa that reported on the occurrence of pfhrp2/pfhrp3 deletions rarely evaluated deletions on the flanking genes. More studies are required to evaluate the existence and extent of these gene deletions, whose presence may lead to delayed or missed treatment. This information will guide appropriate diagnostic approaches in the respective areas.
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Mayor A, Bassat Q. "Resistance" to diagnostics: A serious biological challenge for malaria control and elimination. EBioMedicine 2019; 50:9-10. [PMID: 31812497 PMCID: PMC6921289 DOI: 10.1016/j.ebiom.2019.11.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 11/25/2019] [Indexed: 11/30/2022] Open
Affiliation(s)
- Alfredo Mayor
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Quique Bassat
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique; ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain; Pediatric Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu (University of Barcelona), Barcelona, Spain; Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
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