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Angwe MK, Mwebaza N, Nsobya SL, Vudriko P, Dralabu S, Omali D, Tumwebaze MA, Ocan M. Day 3 parasitemia and Plasmodium falciparum Kelch 13 mutations among uncomplicated malaria patients treated with artemether-lumefantrine in Adjumani district, Uganda. PLoS One 2024; 19:e0305064. [PMID: 38837973 PMCID: PMC11152288 DOI: 10.1371/journal.pone.0305064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 05/22/2024] [Indexed: 06/07/2024] Open
Abstract
Artemisinin resistance threatens malaria control and elimination efforts globally. Recent studies have reported the emergence of Plasmodium falciparum parasites tolerant to artemisinin agents in sub-Saharan Africa, including Uganda. The current study assessed the day 3 parasite clearance and its correlation with P. falciparum K13 propeller gene (pfkelch13) mutations in P. falciparum parasites isolated from patients with uncomplicated malaria under artemether-lumefantrine (AL) treatment. This study enrolled 100 P. falciparum-positive patients to whom AL was prescribed between 09/September/2022 and 06/November/2022. Blood samples were collected in EDTA tubes before treatment initiation (day 0) and on day 3. Parasitemia was assessed by microscopy from blood smears and quantitative polymerase chain reaction (qPCR) from the DNA extracted. The day 0 parasite K13 gene was sequenced using Sanger sequencing. Sequence data were analysed using MEGA version 11 software. The data were analysed using STATA version 15, and the Mann‒Whitney U test was used to compare PCR parasite clearance on day 3 using the comparative CT value method and pfkelch13 mutations. The prevalence of day 3 parasitaemia was 24% (24/100) by microscopy and 63% (63/100) by qPCR from the AL-treated patients. P. falciparum K13-propeller gene polymorphism was detected in 18.8% (15/80) of the day 0 DNA samples. The K13 mutations found were C469Y, 12.5% (10/80); A675V, 2.5% (2/80); A569S, 1.25%, (1/80), A578S, 1.25%, (1/80) and; F491S, 1.25%, (1/80) a new allele not reported anywhere. The C469Y mutation, compared to the wild-type, was associated with delayed parasite clearance p = 0.0278, Hodges-Lehmann estimation 3.2108 on the log scale, (95%CI 1.7076, 4.4730). There was a high prevalence of day 3 P. falciparum among malaria patients treated using artemether-lumefantrine. We conclude the presence of the K13 mutation associated with artemisinin resistance by P. falciparum in Adjumani district, Uganda, necessitates regular surveillance of the effectiveness and efficacy of artemether-lumefantrine in the country.
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Affiliation(s)
- Martin Kamilo Angwe
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University, Kampala, Uganda
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
- Department of Biomolecular Resources and Biolab Sciences, School of Biosecurity, Biotechnical and Laboratory Science, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Norah Mwebaza
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University, Kampala, Uganda
| | - Sam Lubwama Nsobya
- Infectious Diseases Research Collaboration, Makerere University, Kampala, Uganda
| | - Patrick Vudriko
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Saviour Dralabu
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Denis Omali
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University, Kampala, Uganda
- Infectious Disease Institute, Makerere University, Kampala, Uganda
| | - Maria Agnes Tumwebaze
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Moses Ocan
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University, Kampala, Uganda
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Angwe MK, Mwebaza N, Nsobya SL, Vudriko P, Dralabu S, Omali D, Tumwebaze MA, Ocan M. Day 3 parasitemia and Plasmodium falciparum Kelch 13 mutations among uncomplicated malaria patients treated with artemether-lumefantrine in Adjumani district, Uganda. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.04.26.24306433. [PMID: 38712186 PMCID: PMC11071562 DOI: 10.1101/2024.04.26.24306433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Artemisinin resistance threatens malaria control and elimination efforts globally. Recent studies have reported the emergence of Plasmodium falciparum parasites tolerant to artemisinin agents in sub-Saharan Africa, including Uganda. The current study assessed the day 3 parasite clearance and its correlation with P. falciparum K13 propeller gene (pfkelch13) mutations in P. falciparum parasites isolated from patients with uncomplicated malaria under artemether-lumefantrine (AL) treatment. This study enrolled 100 P. falciparum-positive patients to whom AL was prescribed between 09/September/2022 and 06/November/2022. Blood samples were collected in EDTA tubes before treatment initiation (day 0) and on day 3. Parasitemia was assessed by microscopy from blood smears and quantitative polymerase chain reaction (qPCR) from the DNA extracted. The day 0 parasite K13 gene was sequenced using Sanger sequencing. Sequence data were analysed using MEGA version 11 software. The data were analysed using STATA version 15, and the Mann‒Whitney U test was used to compare PCR parasite clearance on day 3 using the comparative CT value method and pfkelch13 mutations. The prevalence of day 3 parasitaemia was 24% (24/100) by microscopy and 63% (63/100) by qPCR from the AL-treated patients. P. falciparum K13-propeller gene polymorphism was detected in 18.8% (15/80) of the day 0 DNA samples. The K13 mutations found were C469Y, 12.5% (10/80); A675V, 2.5% (2/80); A569S, 1.25%, (1/80), A578S, 1.25%, (1/80) and; F491S, 1.25%, (1/80) a new allele not reported anywhere. The C469Y mutation, compared to the wild-type, was associated with delayed parasite clearance p=0.0278, Hodges-Lehmann estimation 3.2108 on the log scale, (95%CI 1.7076, 4.4730). There was a high prevalence of day 3 P. falciparum among malaria patients treated using artemether-lumefantrine. We conclude that the K13 mutation associated with artemisinin resistance by P. falciparum is present in Adjumani district, Uganda. This necessitates regular surveillance of the effectiveness and efficacy of artemether-lumefantrine in the country.
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Affiliation(s)
- Martin Kamilo Angwe
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University
- Department of Biomolecular Resources and Biolab Sciences, School of Biosecurity, Biotechnical and Laboratory Science, College of Veterinary Medicine, Animal Resources and Biosecurity Makerere University
| | - Norah Mwebaza
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University
| | | | - Patrick Vudriko
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University
| | - Savior Dralabu
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University
| | - Denis Omali
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University
- Infectious Disease Institute, Makerere University
| | - Maria Agnes Tumwebaze
- Research Center for Tropical Diseases and Vector Control, Department of Pharmacy, Clinical and Comparative Medicine, School of Veterinary Medicine and Animal Resources, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University
| | - Moses Ocan
- Department of Pharmacology and Therapeutics, College of Health Science, Makerere University
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Nainggolan IRA, Syafutri RD, Sinambela MN, Devina C, Handayani, Hasibuan BS, Chuangchaiya S, Divis PCS, Idris ZM, Permatasari R, Lubis IND. The presence of Plasmodium malariae and Plasmodium knowlesi in near malaria elimination setting in western Indonesia. Malar J 2022; 21:316. [PMCID: PMC9636705 DOI: 10.1186/s12936-022-04335-y] [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: 06/21/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022] Open
Abstract
Background Indonesia is progressing towards malaria elimination. To achieve this goal, intervention measures must be addressed to cover all Plasmodium species. Comprehensive control measures and surveillance programmes must be intensified. This study aims to determine the prevalence of microscopic and submicroscopic malaria in Langkat district, North Sumatera Province, Indonesia. Methods A cross-sectional survey was conducted in six villages in Langkat district, North Sumatera Province in June 2019. Data were recorded using a standardized questionnaire. Finger pricked blood samples were obtained for malaria examination using rapid diagnostic test, thick and thin blood smears, and polymerase chain reaction. Results A total of 342 individuals were included in the study. Of them, one (0.3%) had a microscopic Plasmodium malariae infection, no positive RDT examination, and three (0.9%) were positive for P. malariae (n = 1) and Plasmodium knowlesi (n = 2). The distribution of bed net ownership was owned by 40% of the study participants. The participants had a house within a radius of 100–500 m from the forest (86.3%) and had the housing material of cement floor (56.1%), a tin roof (82.2%), wooden wall (35.7%), bamboo wall (28.1%), and brick wall (21.6%). Conclusion Malaria incidence has substantially decreased in Langkat, North Sumatera, Indonesia. However, submicroscopic infection remains in the population and may contribute to further transmission. Surveillance should include the detection of microscopic undetected parasites, to enable the achievement of malaria elimination.
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Affiliation(s)
| | - Rycha Dwi Syafutri
- grid.413127.20000 0001 0657 4011Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Monica Nadya Sinambela
- grid.413127.20000 0001 0657 4011Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Clara Devina
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Handayani
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Beby Syofiani Hasibuan
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Sriwipa Chuangchaiya
- grid.9723.f0000 0001 0944 049XDepartment of Community Health, Faculty of Public Health, Kasetsart University, Chalermphrakiat Sakon Nakhon Province Campus, 47000 Sakon Nakhon, Thailand
| | - Paul C. S. Divis
- grid.412253.30000 0000 9534 9846Malaria Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak Malaysia
| | - Zulkarnain Md Idris
- grid.412113.40000 0004 1937 1557Department of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Ranti Permatasari
- grid.413127.20000 0001 0657 4011Department of Clinical Pathology, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Inke Nadia Diniyanti Lubis
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
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Johora FT, Kibria MG, Fuehrer HP, Alam MS. A Case of Plasmodium malariae in Bangladesh: A Representation of the Suboptimal Performance of Rapid Diagnostic Approaches in Malaria Elimination Settings. Pathogens 2022; 11:pathogens11101072. [PMID: 36297130 PMCID: PMC9607251 DOI: 10.3390/pathogens11101072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/07/2022] [Accepted: 09/16/2022] [Indexed: 11/29/2022] Open
Abstract
Plasmodium malariae is a neglected human malaria parasite with low parasitemia that often results in the misdiagnosis and underestimation of the actual disease burden of this pathogen. Microscopy is the best diagnostic tool, despite the fact that rapid diagnostic tests (RDTs) are the best surveillance tool for malaria diagnosis in many rural areas for their ease of use in elimination settings. For parasite antigen detection other than P. falciparum, RDTs depend on essential glycolytic Plasmodium proteins, i.e., Plasmodium lactate dehydrogenase (pLDH) and Plasmodium aldolase (pAldo) antigens. There is a lack of species-specific test kits for P. malariae, and overall, its rapid antigenic test accuracy is questionable. False negative results can accelerate the burden of asymptomatic malaria infection and transmission. Here, we report a case of a malaria patient in Bangladesh infected with P. malariae who tested negative on pLDH and pAldo based RDTs. This case provides useful information for health providers to be aware of possible RDT failure and also for the future development of analytically sensitive test kits for P. malariae.
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Affiliation(s)
- Fatema Tuj Johora
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
- Institute for Biomedical Sciences, Georgia State University, Atlanta, GA 30303, USA
| | - Mohammad Golam Kibria
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
- Department of Medical Biochemistry, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Hans-Peter Fuehrer
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria
| | - Mohammad Shafiul Alam
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
- Correspondence:
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Persistence of Residual Submicroscopic P. falciparum Parasitemia following Treatment of Artemether-Lumefantrine in Ethio-Sudan Border, Western Ethiopia. Antimicrob Agents Chemother 2022; 66:e0000222. [PMID: 35993723 PMCID: PMC9487599 DOI: 10.1128/aac.00002-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The emergence of artemisinin-resistant parasites in Africa has had a devastating impact, causing most malaria cases and related deaths reported on the continent. In Ethiopia, artemether-lumefantrine (AL) is the first-line drug for the treatment of uncomplicated falciparum malaria. This study is one of the earliest evaluations of artemether-lumefantrine (AL) efficacy in western Ethiopia, 17 years after the introduction of this drug in the study area. This study aimed at assessing PCR- corrected clinical and parasitological responses at 28 days following AL treatment. Sixty uncomplicated falciparum malaria patients were enrolled, treated with standard doses of AL, and monitored for 28 days with clinical and parasitological assessments from September 15 to December 15, 2020. Microscopy was used for patient recruitment and molecular diagnosis of P. falciparum was performed by Var gene acidic terminal sequence (varATS) real-time PCR on dried blood spots collected from each patient from day 0 and on follow-up days 1, 2, 3, 7, 14, 21, and 28. MspI and msp2 genotyping was done to confirm occurrence of recrudescence. Data entry and analysis were done by using the WHO-designed Excel spreadsheet and SPSS version 20 for Windows. A P value of less or equal to 0.05 was considered significant. From a total of 60 patients enrolled in this efficacy study, 10 were lost to follow-up; the results were analyzed for 50 patients. All the patients were fever-free on day 3. The asexual parasite positivity rate on day 3 was zero. However; 60% of the patients were PCR positive on day 3. PCR positivity on day 3 was more common among patients <15 years old as compared with those ≥15 years old (AOR = 6.44, P = 0.027). Only two patients met the case definition of treatment failure. These patients were classified as a late clinical failure as they showed symptoms of malaria and asexual stages of the parasite detected by microscopy on day 14 of their follow-ups. Hence, the Kaplan-Meier analysis of PCR- corrected adequate clinical and parasitological response (ACPR) rate of AL among study participants was 96% (95% CI: 84.9-99). In seven patients, the residual submicroscopic parasitemia persists from day 0 to day 28 of the follow-up. In addition, 16% (8/50) of patients were PCR- and then turned PCR+ after day 7 of the follow-up. AL remains efficacious for the treatment of uncomplicated falciparum malaria in the study area. However, the persistence of PCR-detected residual submicroscopic parasitemia following AL might compromise this treatment and need careful monitoring.
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Valenciano AL, Gomez-Lorenzo MG, Vega-Rodríguez J, Adams JH, Roth A. In vitro models for human malaria: targeting the liver stage. Trends Parasitol 2022; 38:758-774. [PMID: 35780012 PMCID: PMC9378454 DOI: 10.1016/j.pt.2022.05.014] [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: 02/21/2022] [Revised: 05/27/2022] [Accepted: 05/27/2022] [Indexed: 11/16/2022]
Abstract
The Plasmodium liver stage represents a vulnerable therapeutic target to prevent disease progression as the parasite resides in the liver before clinical representation caused by intraerythrocytic development. However, most antimalarial drugs target the blood stage of the parasite's life cycle, and the few drugs that target the liver stage are lethal to patients with a glucose-6-phosphate dehydrogenase deficiency. Furthermore, implementation of in vitro liver models to study and develop novel therapeutics against the liver stage of human Plasmodium species remains challenging. In this review, we focus on the progression of in vitro liver models developed for human Plasmodium spp. parasites, provide a brief review on important assay requirements, and lastly present recommendations to improve models to enhance the discovery process of novel preclinical therapeutics.
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Affiliation(s)
- Ana Lisa Valenciano
- Center for Global Health and Infectious Diseases, College of Public Health, University of South Florida, Tampa, FL 33612, USA; Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos 28760, Madrid, Spain
| | - Maria G Gomez-Lorenzo
- Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos 28760, Madrid, Spain
| | - Joel Vega-Rodríguez
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - John H Adams
- Center for Global Health and Infectious Diseases, College of Public Health, University of South Florida, Tampa, FL 33612, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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Akinyi MY, Chifwete M, Ndwiga L, Kimenyi KM, Osoti V, Ochola-Oyier LI. A cross-sectional analysis identifies a low prevalence of Plasmodium ovale curtisi infections in symptomatic and asymptomatic individuals in Kilifi county, Kenya. Wellcome Open Res 2022. [DOI: 10.12688/wellcomeopenres.17972.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: The focus on P. falciparum diagnosis has led to an underestimation of the global burden of malaria resulting from neglected Plasmodium species. However, there is still scarce data on the prevalence of P. ovale globally. To address this knowledge gap, data collected from cross-sectional studies in Kilifi county were used to: 1) determine the prevalence of P. ovale curtisi infections; and 2) determine the sensitivity of different diagnostic assays in detecting P. ovale curtisi infections. Methods: A total of 531 individuals were sampled across three study sites in Kilifi County, Kenya between 2009 and 2020. Blood smears were prepared from peripheral blood and screened for Plasmodium parasite stages using light microscopy. Molecular screening involved DNA extraction of dried blood spots and blood in ethylenediaminetetraacetic acid, polymerase chain reaction (PCR) using primers targeting the 18 small ribosomal subunit and sequencing. Results: Microscopy screening revealed that the most prevalent species was P. falciparum (32.0%) followed by P. malariae (9.0%) and then P. ovale (1.5%). PCR screening identified additional P. ovale curtisi positives cases. Overall, 48 (8.2%) out of the 531 individuals harbored P. ovale curtisi infection with the highest prevalence reported in the tertiary health facility, (14.6%, 95% CI 8-23.6%), followed by the primary health facility (8.6%, 95% CI 5.4-11.9%), and the community from a cross-sectional blood survey, (6.5%, 95% CI 3.0-11.8%). Microscopy screening for P. ovale had a low sensitivity of 7% (95% CI 1-19-30%) and a high specificity of 99% (95% CI 98-100%). Sequencing results confirmed the presence of P.ovale curtisi. Conclusions: This study provides baseline data for P.ovale curtisi surveillance in Kilifi County, primarily using PCR to improve diagnosis. These results suggest that malaria elimination and eradication efforts should not only concentrate on P. falciparum but should embrace a holistic approach towards elimination of all Plasmodium species.
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Obonyo CO, Ogutu BR. Quinine plus clindamycin vs artemether-lumefantrine for treatment of uncomplicated falciparum malaria in western Kenya. Malar J 2022; 21:198. [PMID: 35729571 PMCID: PMC9214994 DOI: 10.1186/s12936-022-04222-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Charles O Obonyo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.
| | - Bernhards R Ogutu
- Centre for Clinical Research, Kenya Medical Research Institute, P.O. Box 20778, Nairobi, Kenya
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Fuehrer HP, Campino S, Sutherland CJ. The primate malaria parasites Plasmodium malariae, Plasmodium brasilianum and Plasmodium ovale spp.: genomic insights into distribution, dispersal and host transitions. Malar J 2022; 21:138. [PMID: 35505317 PMCID: PMC9066925 DOI: 10.1186/s12936-022-04151-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 04/05/2022] [Indexed: 01/04/2023] Open
Abstract
During the twentieth century, there was an explosion in understanding of the malaria parasites infecting humans and wild primates. This was built on three main data sources: from detailed descriptive morphology, from observational histories of induced infections in captive primates, syphilis patients, prison inmates and volunteers, and from clinical and epidemiological studies in the field. All three were wholly dependent on parasitological information from blood-film microscopy, and The Primate Malarias” by Coatney and colleagues (1971) provides an overview of this knowledge available at that time. Here, 50 years on, a perspective from the third decade of the twenty-first century is presented on two pairs of primate malaria parasite species. Included is a near-exhaustive summary of the recent and current geographical distribution for each of these four species, and of the underlying molecular and genomic evidence for each. The important role of host transitions in the radiation of Plasmodium spp. is discussed, as are any implications for the desired elimination of all malaria species in human populations. Two important questions are posed, requiring further work on these often ignored taxa. Is Plasmodium brasilianum, circulating among wild simian hosts in the Americas, a distinct species from Plasmodium malariae? Can new insights into the genomic differences between Plasmodium ovale curtisi and Plasmodium ovale wallikeri be linked to any important differences in parasite morphology, cell biology or clinical and epidemiological features?
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Affiliation(s)
- Hans-Peter Fuehrer
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210, Vienna, Austria
| | - Susana Campino
- Department of Infection Biology, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Colin J Sutherland
- Department of Infection Biology, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
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Agonhossou R, Akoton R, Dossou YA, Avokpaho E, Mbama DNJ, Boussougou-Sambe TS, Francis NN, Ndo C, Ntoumi F, Wondji CS, Adegnika AA, Borrmann S, Issifou S, Djogbénou LS. Surveillance of Plasmodium malariae infection among inhabitants of rural areas in Ouidah-Kpomasse-Tori Bossito health district, Benin. Parasitol Res 2022; 121:275-286. [PMID: 34981216 DOI: 10.1007/s00436-021-07398-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/23/2021] [Indexed: 10/19/2022]
Abstract
Among the Plasmodium species that infect humans, P. falciparum has been largely studied in malaria endemic areas. However, P. malariae infection is less documented among the human population. This study aimed to monitor the prevalence and distribution of P. malariae in Southern Benin. A cross-sectional survey was conducted in rural localities in the Ouidah-Kpomasse-Tori Bossito (OKT) health district in Southern Benin from June to October 2019. Socio-demographic data were collected using a questionnaire, while malaria infection data were obtained on the one hand by microscopy diagnosis and, on the other, by nested polymerase chain reaction (PCR). Based on microscopy, the prevalence of P. malariae mono-infection and coinfection of P. falciparum, P. malariae was respectively 2.3% and 1.2% in the OKT health district. This prevalence was higher (P < 0.01) than that reported by Damien et al. (2010) 10 years ago in the same study area with 0.7% and 0.3% of P. malariae and P. falciparum/P. malariae, respectively. Based on PCR analysis, P. malariae prevalence was 14.1%, including 5.2% of mono-infection and 8.9% of mixed infection with P. falciparum. Sub-microscopic Plasmodium infections were high (30.6%) and more pronounced in older participants (>20 years). The present study revealed that P. malariae increased in the OKT health district with a high prevalence of submicroscopic infection. Since our results provide valuable evidence of increasing P. malariae infection, the National Malaria Control Programs (NMCPs) must consider P. malariae when designing future measures for effective control and malaria treatment.
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Affiliation(s)
- Romuald Agonhossou
- Tropical Infectious Diseases Research Centre (TIDRC), University of Abomey-Calavi, 01BP 526, Cotonou, Benin
- Fondation Pour la Recherche Scientifique (FORS), ISBA, BP : 88, Cotonou, Bénin
| | - Romaric Akoton
- Tropical Infectious Diseases Research Centre (TIDRC), University of Abomey-Calavi, 01BP 526, Cotonou, Benin.
- Fondation Pour la Recherche Scientifique (FORS), ISBA, BP : 88, Cotonou, Bénin.
| | - Yannelle A Dossou
- Fondation Pour la Recherche Scientifique (FORS), ISBA, BP : 88, Cotonou, Bénin
| | - Euripide Avokpaho
- Fondation Pour la Recherche Scientifique (FORS), ISBA, BP : 88, Cotonou, Bénin
| | - Dollon N J Mbama
- Fondation Congolaise pour la Recherche Medicale (FCRM), Brazzaville, Congo
- Université Marien Ngouabi, Brazzaville, Congo
| | - Terence S Boussougou-Sambe
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Nongley N Francis
- Department of Parasitology and Medical Entomology, Centre for Research in Infectious Diseases (CRID), Centre Region, Yaounde, 237, Cameroon
- Department of Microbiology and Parasitology, University of Buea, South West, Buea, 237, Cameroon
| | - Cyrille Ndo
- Department of Parasitology and Medical Entomology, Centre for Research in Infectious Diseases (CRID), Centre Region, Yaounde, 237, Cameroon
| | - Francine Ntoumi
- Fondation Congolaise pour la Recherche Medicale (FCRM), Brazzaville, Congo
- Université Marien Ngouabi, Brazzaville, Congo
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Charles S Wondji
- Department of Parasitology and Medical Entomology, Centre for Research in Infectious Diseases (CRID), Centre Region, Yaounde, 237, Cameroon
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Ayola A Adegnika
- Fondation Pour la Recherche Scientifique (FORS), ISBA, BP : 88, Cotonou, Bénin
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
- Eberhard Karls Universität Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Saadou Issifou
- Fondation Pour la Recherche Scientifique (FORS), ISBA, BP : 88, Cotonou, Bénin
| | - Luc S Djogbénou
- Tropical Infectious Diseases Research Centre (TIDRC), University of Abomey-Calavi, 01BP 526, Cotonou, Benin
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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11
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Ayo D, Odongo B, Omara J, Andolina C, Mulder O, Staedke SG, Bousema T. Plasmodium malariae infections as a cause of febrile disease in an area of high Plasmodium falciparum transmission intensity in Eastern Uganda. Malar J 2021; 20:425. [PMID: 34715876 PMCID: PMC8555357 DOI: 10.1186/s12936-021-03962-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 10/20/2021] [Indexed: 11/18/2022] Open
Abstract
Background Plasmodium falciparum is responsible for the vast majority of (severe) clinical malaria cases in most African settings. Other Plasmodium species often go undiagnosed but may still have clinical consequences. Case presentation Here, five cases of Plasmodium malariae infections from Eastern Uganda (aged 2–39 years) are presented. These infections were all initially mistaken for P. falciparum, but Plasmodium schizonts (up to 2080/µL) were identified by microscopy. Clinical signs included history of fever and mild anaemia. Conclusion These findings highlight the importance of considering non-falciparum species as the cause of clinical malaria. In areas of intense P. falciparum transmission, where rapid diagnostic tests that detect only P. falciparum antigens are commonly used, non-falciparum malaria cases may be missed.
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Affiliation(s)
- Daniel Ayo
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Bakar Odongo
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Joseph Omara
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Chiara Andolina
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Ole Mulder
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Sarah G Staedke
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. .,Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK.
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12
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Nundu SS, Culleton R, Simpson SV, Arima H, Muyembe JJ, Mita T, Ahuka S, Yamamoto T. Malaria parasite species composition of Plasmodium infections among asymptomatic and symptomatic school-age children in rural and urban areas of Kinshasa, Democratic Republic of Congo. Malar J 2021; 20:389. [PMID: 34600558 PMCID: PMC8487491 DOI: 10.1186/s12936-021-03919-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Malaria remains a major public health concern in the Democratic Republic of Congo (DRC), and school-age children are relatively neglected in malaria prevalence surveys and may constitute a significant reservoir of transmission. This study aimed to understand the burden of malaria infections in school-age children in Kinshasa/DRC. METHODS A total of 634 (427 asymptomatic and 207 symptomatic) blood samples collected from school-age children aged 6 to 14 years were analysed by microscopy, RDT and Nested-PCR. RESULTS The overall prevalence of Plasmodium spp. by microscopy, RDT and PCR was 33%, 42% and 62% among asymptomatic children and 59%, 64% and 95% in symptomatic children, respectively. The prevalence of Plasmodium falciparum, Plasmodium malariae and Plasmodium ovale spp. by PCR was 58%, 20% and 11% among asymptomatic and 93%, 13% and 16% in symptomatic children, respectively. Among P. ovale spp., P. ovale curtisi, P. ovale wallikeri and mixed P. ovale curtisi + P. ovale wallikeri accounted for 75%, 24% and 1% of infections, respectively. All Plasmodium species infections were significantly more prevalent in the rural area compared to the urban area in asymptomatic infections (p < 0.001). Living in a rural as opposed to an urban area was associated with a five-fold greater risk of asymptomatic malaria parasite carriage (p < 0.001). Amongst asymptomatic malaria parasite carriers, 43% and 16% of children harboured mixed Plasmodium with P. falciparum infections in the rural and the urban areas, respectively, whereas in symptomatic malaria infections, it was 22% and 26%, respectively. Few children carried single infections of P. malariae (2.2%) and P. ovale spp. (1.9%). CONCLUSION School-age children are at significant risk from both asymptomatic and symptomatic malaria infections. Continuous systematic screening and treatment of school-age children in high-transmission settings is needed.
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Affiliation(s)
- Sabin S Nundu
- Department of International Health and Medical Anthropology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
- Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Nagasaki University, Nagasaki, Japan
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo
| | - Richard Culleton
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Ehime, Japan.
| | - Shirley V Simpson
- Department of International Health and Medical Anthropology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
- Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Nagasaki University, Nagasaki, Japan
| | - Hiroaki Arima
- Department of International Health and Medical Anthropology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Jean-Jacques Muyembe
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo
| | - Toshihiro Mita
- Department of Tropical Medicine and Parasitology, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Steve Ahuka
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo
| | - Taro Yamamoto
- Department of International Health and Medical Anthropology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
- Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Nagasaki University, Nagasaki, Japan
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13
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Ansah F, Suurbaar J, Darko D, Anabire NG, Blankson SO, Domson BKS, Soulama A, Kpasra P, Chirawurah JD, Amenga-Etego L, Kanyong P, Awandare GA, Aniweh Y. Development of Cooperative Primer-Based Real-Time PCR Assays for the Detection of Plasmodium malariae and Plasmodium ovale. J Mol Diagn 2021; 23:1393-1403. [PMID: 34425259 PMCID: PMC8591562 DOI: 10.1016/j.jmoldx.2021.07.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 06/16/2021] [Accepted: 07/14/2021] [Indexed: 11/27/2022] Open
Abstract
Plasmodium malariae and Plasmodium ovale are increasingly gaining public health attention as the global transmission of falciparum malaria is decreasing. However, the absence of reliable Plasmodium species-specific detection tools has hampered accurate diagnosis of these minor Plasmodium species. In this study, SYBR Green-based real-time PCR assays were developed for the detection of P. malariae and P. ovale using cooperative primers that significantly limit the formation and propagation of primers-dimers. Both the P. malariae and P. ovale cooperative primer-based assays had at least 10-fold lower detection limit compared with the corresponding conventional primer-based assays. More important, the cooperative primer-based assays were evaluated in a cross-sectional study using 560 samples obtained from two health facilities in Ghana. The prevalence rates of P. malariae and P. ovale among the combined study population were 18.6% (104/560) and 5.5% (31/560), respectively. Among the Plasmodium-positive cases, P. malariae and P. ovale mono-infections were 3.6% (18/499) and 1.0% (5/499), respectively, with the remaining being co-infections with Plasmodium falciparum. The study demonstrates the public health importance of including detection tools with lower detection limits in routine diagnosis and surveillance of nonfalciparum species. This will be necessary for comprehensively assessing the effectiveness of malaria interventions and control measures aimed toward global malaria elimination.
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Affiliation(s)
- Felix Ansah
- West African Centre for Cell Biology of Infectious Pathogens, 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
| | - Jonathan Suurbaar
- West African Centre for Cell Biology of Infectious Pathogens, 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
| | - Derrick Darko
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Nsoh G Anabire
- West African Centre for Cell Biology of Infectious Pathogens, 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; Department of Biochemistry and Molecular Medicine, School of Medicine, University for Development Studies, Tamale, Ghana
| | - Samuel O Blankson
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Bright K S Domson
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Alamissa Soulama
- West African Centre for Cell Biology of Infectious Pathogens, 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
| | - Paulina Kpasra
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Jersley D Chirawurah
- West African Centre for Cell Biology of Infectious Pathogens, 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
| | - Lucas Amenga-Etego
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Prosper Kanyong
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana; Flexmedical Solutions Ltd., Eliburn Industrial Park, Livingston, United Kingdom
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens, 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, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana.
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14
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Serrano D, Santos-Reis A, Silva C, Dias A, Dias B, Toscano C, Conceição C, Baptista-Fernandes T, Nogueira F. Imported Malaria in Portugal: Prevalence of Polymorphisms in the Anti-Malarial Drug Resistance Genes pfmdr1 and pfk13. Microorganisms 2021; 9:microorganisms9102045. [PMID: 34683365 PMCID: PMC8538333 DOI: 10.3390/microorganisms9102045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/18/2021] [Accepted: 09/21/2021] [Indexed: 02/04/2023] Open
Abstract
Malaria is one of the ‘big three’ killer infectious diseases, alongside tuberculosis and HIV. In non-endemic areas, malaria may occur in travelers who have recently been to or visited endemic regions. The number of imported malaria cases in Portugal has increased in recent years, mostly due to the close relationship with the community of Portuguese language countries. Samples were collected from malaria-infected patients attending Centro Hospitalar Lisboa Ocidental (CHLO) or the outpatient clinic of Instituto de Higiene e Medicina Tropical (IHMT-NOVA) between March 2014 and May 2021. Molecular characterization of Plasmodium falciparum pfk13 and pfmdr1 genes was performed. We analyzed 232 imported malaria cases. The majority (68.53%) of the patients came from Angola and only three patients travelled to a non-African country; one to Brazil and two to Indonesia. P. falciparum was diagnosed in 81.47% of the cases, P. malariae in 7.33%, P. ovale 6.47% and 1.72% carried P. vivax. No mutations were detected in pfk13. Regarding pfmdr1, the wild-type haplotype (N86/Y184/D1246) was also the most prevalent (64.71%) and N86/184F/D1246 was detected in 26.47% of the cases. The typical imported malaria case was middle-aged male, traveling from Angola, infected with P. falciparum carrying wild type pfmdr1 and pfk13. Our study highlights the need for constant surveillance of malaria parasites imported into Portugal as an important pillar of public health.
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Affiliation(s)
- Debora Serrano
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (IHMT-NOVA), Rua da Junqueira 100, 1349-008 Lisboa, Portugal; (D.S.); (A.S.-R.); (C.S.); (B.D.); (C.C.)
| | - Ana Santos-Reis
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (IHMT-NOVA), Rua da Junqueira 100, 1349-008 Lisboa, Portugal; (D.S.); (A.S.-R.); (C.S.); (B.D.); (C.C.)
| | - Clemente Silva
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (IHMT-NOVA), Rua da Junqueira 100, 1349-008 Lisboa, Portugal; (D.S.); (A.S.-R.); (C.S.); (B.D.); (C.C.)
| | - Ana Dias
- Laboratório de Microbiologia Clínica e Biologia Molecular, Serviço de Patologia Clínica, Centro Hospitalar Lisboa Ocidental (CHLO), Rua da Junqueira 126, 1349-019 Lisboa, Portugal; (A.D.); (C.T.); (T.B.-F.)
| | - Brigite Dias
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (IHMT-NOVA), Rua da Junqueira 100, 1349-008 Lisboa, Portugal; (D.S.); (A.S.-R.); (C.S.); (B.D.); (C.C.)
| | - Cristina Toscano
- Laboratório de Microbiologia Clínica e Biologia Molecular, Serviço de Patologia Clínica, Centro Hospitalar Lisboa Ocidental (CHLO), Rua da Junqueira 126, 1349-019 Lisboa, Portugal; (A.D.); (C.T.); (T.B.-F.)
| | - Cláudia Conceição
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (IHMT-NOVA), Rua da Junqueira 100, 1349-008 Lisboa, Portugal; (D.S.); (A.S.-R.); (C.S.); (B.D.); (C.C.)
| | - Teresa Baptista-Fernandes
- Laboratório de Microbiologia Clínica e Biologia Molecular, Serviço de Patologia Clínica, Centro Hospitalar Lisboa Ocidental (CHLO), Rua da Junqueira 126, 1349-019 Lisboa, Portugal; (A.D.); (C.T.); (T.B.-F.)
| | - Fatima Nogueira
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (IHMT-NOVA), Rua da Junqueira 100, 1349-008 Lisboa, Portugal; (D.S.); (A.S.-R.); (C.S.); (B.D.); (C.C.)
- Correspondence: ; Tel.: +351-213652600
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15
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Akala HM, Watson OJ, Mitei KK, Juma DW, Verity R, Ingasia LA, Opot BH, Okoth RO, Chemwor GC, Juma JA, Mwakio EW, Brazeau N, Cheruiyot AC, Yeda RA, Maraka MN, Okello CO, Kateete DP, Managbanag JR, Andagalu B, Ogutu BR, Kamau E. Plasmodium interspecies interactions during a period of increasing prevalence of Plasmodium ovale in symptomatic individuals seeking treatment: an observational study. LANCET MICROBE 2021; 2:e141-e150. [DOI: 10.1016/s2666-5247(21)00009-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 12/07/2020] [Accepted: 01/15/2021] [Indexed: 11/28/2022]
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16
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Oriero EC, Amenga-Etego L, Ishengoma DS, Amambua-Ngwa A. Plasmodium malariae, current knowledge and future research opportunities on a neglected malaria parasite species. Crit Rev Microbiol 2021; 47:44-56. [PMID: 33507842 DOI: 10.1080/1040841x.2020.1838440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Plasmodium malariae is often reported as a benign malaria parasite. There are limited data on its biology and disease burden in sub-Saharan Africa (sSA) possibly due to the unavailability of specific and affordable tools for routine diagnosis and large epidemiology studies. In addition, P. malariae occurs at low parasite densities and in co-infections with other species, predominately P. falciparum. The paucity of data on P. malariae infections limits the capacity to accurately determine its contribution to malaria and the effect of control interventions against P. falciparum on its prevalence. Here, we summarise the current knowledge on P. malariae epidemiology in sSA - overall prevalence ranging from 0-32%, as detected by different diagnostic methods; seroprevalence ranging from 0-56% in three countries (Mozambique, Benin and Zimbabwe), and explore the future application of next-generation sequencing technologies as a tool for enriching P. malariae genomic epidemiology. This will provide insights into important adaptive mechanisms of this neglected non-falciparum species, including antimalarial drug resistance, local and regional parasite transmission patterns and genomic signatures of selection. Improved diagnosis and genomic surveillance of non-falciparum malaria parasites in Africa would be helpful in evaluating progress towards elimination of all human Plasmodium species.
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Affiliation(s)
- Eniyou C Oriero
- Disease Control and Elimination Theme, Medical Research Council Unit The Gambia at LSHTM, Fajara, The Gambia
| | - Lucas Amenga-Etego
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Ghana
| | - Deus S Ishengoma
- Tanga Research Centre, National Institute for Medical Research, Tanga, Tanzania
| | - Alfred Amambua-Ngwa
- Disease Control and Elimination Theme, Medical Research Council Unit The Gambia at LSHTM, Fajara, The Gambia
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17
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Woodford J, Collins KA, Odedra A, Wang C, Jang IK, Domingo GJ, Watts R, Marquart L, Berriman M, Otto TD, McCarthy JS. An Experimental Human Blood-Stage Model for Studying Plasmodium malariae Infection. J Infect Dis 2020; 221:948-955. [PMID: 30852586 DOI: 10.1093/infdis/jiz102] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 03/06/2019] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Plasmodium malariae is considered a minor malaria parasite, although its global disease burden is underappreciated. The aim of this study was to develop an induced blood-stage malaria (IBSM) model of P. malariae to study parasite biology, diagnostic assays, and treatment. METHODS This clinical trial involved 2 healthy subjects who were intravenously inoculated with cryopreserved P. malariae-infected erythrocytes. Subjects were treated with artemether-lumefantrine after development of clinical symptoms. Prior to antimalarial therapy, mosquito-feeding assays were performed to investigate transmission, and blood samples were collected for rapid diagnostic testing and parasite transcription profiling. Serial blood samples were collected for biomarker analysis. RESULTS Both subjects experienced symptoms and signs typical of early malaria. Parasitemia was detected 7 days after inoculation, and parasite concentrations increased until antimalarial treatment was initiated 25 and 21 days after inoculation for subjects 1 and 2 respectively (peak parasitemia levels, 174 182 and 50 291 parasites/mL, respectively). The parasite clearance half-life following artemether-lumefantrine treatment was 6.7 hours. Mosquito transmission was observed for 1 subject, while in vivo parasite transcription and biomarkers were successfully profiled. CONCLUSIONS An IBSM model of P. malariae has been successfully developed and may be used to study the biology of, diagnostic testing for, and treatment of this neglected malaria species. CLINICAL TRIALS REGISTRATION ACTRN12617000048381.
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Affiliation(s)
- John Woodford
- QIMR Berghofer Medical Research Institute
- The University of Queensland
| | | | | | - Claire Wang
- Queensland Paediatric Infectious Diseases Laboratory, Brisbane, Australia
| | | | | | | | | | | | - Thomas D Otto
- Wellcome Sanger Institute, Hinxton
- Centre of Immunobiology, Institute of Infection, Immunity, and Inflammation, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - James S McCarthy
- QIMR Berghofer Medical Research Institute
- The University of Queensland
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18
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Sutherland CJ. A New Window on Plasmodium malariae Infections. J Infect Dis 2020; 221:864-866. [PMID: 30855671 DOI: 10.1093/infdis/jiz103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 03/06/2019] [Indexed: 11/14/2022] Open
Affiliation(s)
- Colin J Sutherland
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
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19
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Oriero EC, Olukosi AY, Oduwole OA, Djimde A, D'Alessandro U, Meremikwu MM, Amambua-Ngwa A. Seroprevalence and Parasite Rates of Plasmodium malariae in a High Malaria Transmission Setting of Southern Nigeria. Am J Trop Med Hyg 2020; 103:2208-2216. [PMID: 33124531 PMCID: PMC7695047 DOI: 10.4269/ajtmh.20-0593] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Although Plasmodium falciparum continues to be the main target for malaria elimination, other Plasmodium species persist in Africa. Their clinical diagnosis is uncommon, whereas rapid diagnostic tests (RDTs), the most widely used malaria diagnostic tools, are only able to distinguish between P. falciparum and non-falciparum species, the latter as “pan-species.” Blood samples from health facilities were collected in southern Nigeria (Lagos and Calabar) in 2017 (October–December) and Calabar only in 2018 (October–November), and analyzed by several methods, namely, microscopy, quantitative real-time PCR (qPCR), and peptide serology targeting candidate antigens (Plasmodium malariae apical membrane antigen, P. malariae lactose dehydrogenase, and P. malariae circumsporozoite surface protein). Both microscopy and qPCR diagnostic approaches detected comparable proportions (∼80%) of all RDT-positive samples infected with the dominant P. falciparum malaria parasite. However, higher proportions of non-falciparum species were detected by qPCR than microscopy, 10% against 3% infections for P. malariae and 3% against 0% for Plasmodium ovale, respectively. No Plasmodium vivax infection was detected. Infection rates for P. malariae varied between age-groups, with the highest rates in individuals aged > 5 years. Plasmodium malariae–specific seroprevalence rates fluctuated in those aged < 10 years but generally reached the peak around 20 years of age for all peptides. The heterogeneity and rates of these non-falciparum species call for increased specific diagnosis and targeting by elimination strategies.
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Affiliation(s)
- Eniyou C Oriero
- Medical Research Council Unit The Gambia at LSHTM, Banjul, The Gambia
| | | | - Olabisi A Oduwole
- Calabar Institute of Tropical Disease Research and Prevention, University of Calabar Teaching Hospital, Calabar, Nigeria
| | - Abdoulaye Djimde
- Department of Epidemiology of Parasitic Diseases, Malaria Research and Training Center, University of Science, Techniques and Technology of Bamako, Bamako, Mali
| | | | - Martin M Meremikwu
- Calabar Institute of Tropical Disease Research and Prevention, University of Calabar Teaching Hospital, Calabar, Nigeria
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20
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Xie Y, Wu K, Cheng W, Jiang T, Yao Y, Xu M, Yang Y, Tan H, Li J. Molecular epidemiological surveillance of Africa and Asia imported malaria in Wuhan, Central China: comparison of diagnostic tools during 2011-2018. Malar J 2020; 19:321. [PMID: 32883296 PMCID: PMC7470674 DOI: 10.1186/s12936-020-03387-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 08/25/2020] [Indexed: 01/17/2023] Open
Abstract
Background Malaria remains a serious public health problem globally. As the elimination of indigenous malaria continues in China, imported malaria has gradually become a major health hazard. Well-timed and accurate diagnoses could support the timely implementation of therapeutic schedules, reveal the prevalence of imported malaria and avoid transmission of the disease. Methods Blood samples were collected in Wuhan, China, from August 2011 to December 2018. All patients accepted microscopy and rapid diagnosis test (RDT) examinations. Subsequently, each of the positive or suspected positive cases was tested for four human-infectious Plasmodium species by using 18S rRNA-based nested PCR and Taqman probe-based real-time PCR. The results of the microscopy and the two molecular diagnostic methods were analysed. Importation origins were traced by country, and the prevalence of Plasmodium species was analysed by year. Results A total of 296 blood samples, including 288 that were microscopy and RDT positive, 7 RDT and Plasmodium falciparum positive, and 1 suspected case, were collected and reanalysed. After application of the two molecular methods and sequencing, 291 cases including 245 P. falciparum, 15 Plasmodium vivax, 20 Plasmodium ovale, 6 Plasmodium malariae and 5 mixed infections (3 P. falciparum + P. ovale, 2 P. vivax + P. ovale) were confirmed. These patients had returned from Africa (95.53%) and Asia (4.47%). Although the prevalence displayed a small-scale fluctuation, the overall trend of the imported cases increased yearly. Conclusions These results emphasize the necessity of combined utilization of the four tools for malaria diagnosis in clinic and in field surveys of potential risk regions worldwide including Wuhan.
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Affiliation(s)
- Yiting Xie
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Kai Wu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Weijia Cheng
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Tingting Jiang
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Yi Yao
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Mingxing Xu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Yan Yang
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Huabing Tan
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Jian Li
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China. .,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.
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21
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Selective whole genome amplification of Plasmodium malariae DNA from clinical samples reveals insights into population structure. Sci Rep 2020; 10:10832. [PMID: 32616738 PMCID: PMC7331648 DOI: 10.1038/s41598-020-67568-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 06/05/2020] [Indexed: 02/03/2023] Open
Abstract
The genomic diversity of Plasmodium malariae malaria parasites is understudied, partly because infected individuals tend to present with low parasite densities, leading to difficulties in obtaining sufficient parasite DNA for genome analysis. Selective whole genome amplification (SWGA) increases the relative levels of pathogen DNA in a clinical sample, but has not been adapted for P. malariae parasites. Here we design customized SWGA primers which successfully amplify P. malariae DNA extracted directly from unprocessed clinical blood samples obtained from patients with P. malariae-mono-infections from six countries, and further test the efficacy of SWGA on mixed infections with other Plasmodium spp. SWGA enables the successful whole genome sequencing of samples with low parasite density (i.e. one sample with a parasitaemia of 0.0064% resulted in 44% of the genome covered by ≥ 5 reads), leading to an average 14-fold increase in genome coverage when compared to unamplified samples. We identify a total of 868,476 genome-wide SNPs, of which 194,709 are unique across 18 high-quality isolates. After exclusion of the hypervariable subtelomeric regions, a high-quality core subset of 29,899 unique SNPs is defined. Population genetic analysis suggests that P. malariae parasites display clear geographical separation by continent. Further, SWGA successfully amplifies genetic regions of interest such as orthologs of P. falciparum drug resistance-associated loci (Pfdhfr, Pfdhps, Pfcrt, Pfk13 and Pfmdr1), and several non-synonymous SNPs were detected in these genes. In conclusion, we have established a robust SWGA approach that can assist whole genome sequencing of P. malariae, and thereby facilitate the implementation of much-needed large-scale multi-population genomic studies of this neglected malaria parasite. As demonstrated in other Plasmodia, such genetic diversity studies can provide insights into the biology underlying the disease and inform malaria surveillance and control measures.
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22
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Lubis IND, Wijaya H, Lubis M, Lubis CP, Beshir KB, Staedke SG, Sutherland CJ. Recurrence of Plasmodium malariae and P. falciparum Following Treatment of Uncomplicated Malaria in North Sumatera With Dihydroartemisinin-Piperaquine or Artemether-Lumefantrine. Open Forum Infect Dis 2020; 7:ofaa116. [PMID: 32420402 PMCID: PMC7216766 DOI: 10.1093/ofid/ofaa116] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/01/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND We assessed the efficacy of artemisinin-based combination therapies for treatment of uncomplicated falciparum malaria, with or without co-infecting Plasmodium spp., in Sumatera, Indonesia. METHODS Febrile patients aged >6 months with uncomplicated P. falciparum were randomized to receive dihydroartemisinin-piperaquine or artemether-lumefantrine, plus single-dose primaquine, and were followed for 42 days. Mixed Plasmodium infections were included; P. vivax infections received 14 days of primaquine. We retrospectively restricted the analysis to cases with polymerase chain reaction (PCR)-confirmed parasitemia. Recurrent parasitemia in follow-up was identified by species-specific nested PCR. RESULTS Of the 3731 participants screened, 302 were enrolled and randomized. In the dihydroartemisinin-piperaquine arm, P. falciparum infections were confirmed by PCR in 59 participants, with mixed infections in 23 (39.0%). In the artemether-lumefantrine arm, P. falciparum infections were confirmed by PCR in 55 participants, with mixed infections in 16 (29.0%). Both regimens were well tolerated, and symptoms improved rapidly in all treated participants. In the dihydroartemisinin-piperaquine arm, 1 P. falciparum recurrence (on day 7) and 6 P. malariae recurrences (1 had a mixed infection with P. falciparum) were identified during days 3-42 of follow-up. In the artemether-lumefantrine arm, 1 P. falciparum/P. malariae/P. vivax recurrence occurred on day 35. Submicroscopic persistence occurred during follow-up in 21 (37%) of 57 receiving dihydroartemisinin-piperaquine and 20 (39%) of 51 receiving artemether-lumefantrine. CONCLUSIONS In Sumatera, both regimens effectively cleared initial parasitemia, but P. falciparum and P. malariae persisted in some individuals. Molecular species detection should be deployed in antimalarial efficacy trials in Indonesia. TRIAL REGISTRATION NCT02325180.
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Affiliation(s)
- Inke Nadia D Lubis
- Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia
- Infection and Immunity Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Hendri Wijaya
- Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia
| | - Munar Lubis
- Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia
| | - Chairuddin P Lubis
- Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia
| | - Khalid B Beshir
- Infection and Immunity Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sarah G Staedke
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Colin J Sutherland
- Infection and Immunity Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- PHE Malaria Reference Laboratory, London School of Hygiene and Tropical Medicine, London, United Kingdom
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23
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Mwaiswelo R, Ngasala B. Evaluation of residual submicroscopic Plasmodium falciparum parasites 3 days after initiation of treatment with artemisinin-based combination therapy. Malar J 2020; 19:162. [PMID: 32316974 PMCID: PMC7175519 DOI: 10.1186/s12936-020-03235-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 04/15/2020] [Indexed: 11/25/2022] Open
Abstract
Plasmodium falciparum resistance against artemisinin has not emerged in Africa; however, there are reports of the presence of polymerase chain reaction-determined residual submicroscopic parasitaemia detected on day 3 after artemisinin-based combination therapy (ACT). These residual submicroscopic parasites are thought to represent tolerant/resistant parasites against artemisinin, the fast-acting component of the combination. This review focused on residual submicroscopic parasitaemia, what it represents, and its significance on the emergence and spread of artemisinin resistance in Africa. Presence of residual submicroscopic parasitemia on day 3 after treatment initiation leaves question on whether successful treatment is attained with ACT. Thus there is a need to determine the potential public health implication of the PCR-determined residual submicroscopic parasitaemia observed on day 3 after ACT. Robust techniques, such as in vitro cultivation, should be used to evaluate if the residual submicroscopic parasites detected on day 3 after ACT are viable asexual parasites, or gametocytes, or the DNA of the dead parasites waiting to be cleared from the circulation. Such techniques would also evaluate the transmissibility of these residual parasites.
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Affiliation(s)
- Richard Mwaiswelo
- Department of Microbiology, Immunology and Parasitology, Hubert Kairuki Memorial University, Dar es Salaam, Tanzania. .,Department of Parasitology and Medical Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania.
| | - Bill Ngasala
- Department of Parasitology and Medical Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
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24
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Tang J, Templeton TJ, Cao J, Culleton R. The Consequences of Mixed-Species Malaria Parasite Co-Infections in Mice and Mosquitoes for Disease Severity, Parasite Fitness, and Transmission Success. Front Immunol 2020; 10:3072. [PMID: 32038623 PMCID: PMC6987389 DOI: 10.3389/fimmu.2019.03072] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 12/16/2019] [Indexed: 11/13/2022] Open
Abstract
The distributions of human malaria parasite species overlap in most malarious regions of the world, and co-infections involving two or more malaria parasite species are common. Little is known about the consequences of interactions between species during co-infection for disease severity and parasite transmission success. Anti-malarial interventions can have disproportionate effects on malaria parasite species and may locally differentially reduce the number of species in circulation. Thus, it is important to have a clearer understanding of how the interactions between species affect disease and transmission dynamics. Controlled competition experiments using human malaria parasites are impossible, and thus we assessed the consequences of mixed-species infections on parasite fitness, disease severity, and transmission success using the rodent malaria parasite species Plasmodium chabaudi, Plasmodium yoelii, and Plasmodium vinckei. We compared the fitness of individual species within single species and co-infections in mice. We also assessed the disease severity of single vs. mixed infections in mice by measuring mortality rates, anemia, and weight loss. Finally, we compared the transmission success of parasites in single or mixed species infections by quantifying oocyst development in Anopheles stephensi mosquitoes. We found that co-infections of P. yoelii with either P. vinckei or P. chabaudi led to a dramatic increase in infection virulence, with 100% mortality observed in mixed species infections, compared to no mortality for P. yoelii and P. vinckei single infections, and 40% mortality for P. chabaudi single infections. The increased mortality in the mixed infections was associated with an inability to clear parasitaemia, with the non-P. yoelii parasite species persisting at higher parasite densities than in single infections. P. yoelii growth was suppressed in all mixed infections compared to single infections. Transmissibility of P. vinckei and P. chabaudi to mosquitoes was also reduced in the presence of P. yoelii in co-infections compared to single infections. The increased virulence of co-infections containing P. yoelii (reticulocyte restricted) and P. chabaudi or P. vinckei (predominantly normocyte restricted) may be due to parasite cell tropism and/or immune modulation of the host. We explain the reduction in transmission success of species in co-infections in terms of inter-species gamete incompatibility.
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Affiliation(s)
- Jianxia Tang
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China.,Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Thomas J Templeton
- Department of Protozoology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Jun Cao
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Richard Culleton
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
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25
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Exploring Antimalarial Herbal Plants across Communities in Uganda Based on Electronic Data. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:3057180. [PMID: 31636682 PMCID: PMC6766105 DOI: 10.1155/2019/3057180] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 08/14/2019] [Indexed: 12/14/2022]
Abstract
Malaria is one of the most rampant diseases today not only in Uganda but also throughout Africa. Hence, it needs very close attention as it can be severe, causing many deaths, especially due to the rising prevalence of pathogenic resistance to current antimalarial drugs. The majority of the Ugandan population relies on traditional herbal medicines for various health issues. Thus, herein, we review various plant resources used to treat malaria across communities in Uganda so as to provide comprehensive and valuable ethnobotanical data about these plants. Approximately 182 plant species from 63 different plant families are used for malaria treatment across several communities in Uganda, of which 112 plant species have been investigated for antimalarial activities and 96% of the plant species showing positive results. Some plants showed very strong antimalarial activities and could be investigated further for the identification and validation of potentially therapeutic antimalarial compounds. There is no record of an investigation of antimalarial activity for approximately 39% of the plant species used for malaria treatment, yet these plants could be potential sources for potent antimalarial remedies. Thus, the review provides guidance for areas of further research on potential plant resources that could be sources of compounds with therapeutic properties for the treatment of malaria. Some of the plants were investigated for antimalarial activities, and their efficacy, toxicity, and safety aspects still need to be studied.
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26
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Roth JM, Sawa P, Omweri G, Makio N, Osoti V, de Jong MD, Schallig HDFH, Mens PF. Molecular Detection of Residual Parasitemia after Pyronaridine-Artesunate or Artemether-Lumefantrine Treatment of Uncomplicated Plasmodium falciparum Malaria in Kenyan Children. Am J Trop Med Hyg 2019; 99:970-977. [PMID: 30105967 DOI: 10.4269/ajtmh.18-0233] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Artemisinin resistance is rapidly rising in Southeast Asia and may spread to African countries, where efficacy estimates are currently still excellent. Extensive monitoring of parasite clearance dynamics after treatment is needed to determine whether responsiveness to artemisinin-based combination therapies (ACT) is changing in Africa. In this study, Kenyan children with uncomplicated falciparum malaria were randomly assigned to pyronaridine-artesunate (PA) or artemether-lumefantrine (AL) treatment. Parasite clearance was evaluated over 7 days following the start of treatment by quantitative polymerase chain reaction (qPCR) and direct-on-blood PCR nucleic acid lateral flow immunoassay (db-PCR-NALFIA), a simplified molecular malaria diagnostic. Residual parasitemia at day 7 was detected by qPCR in 37.1% (26/70) of AL-treated children and in 46.1% (35/76) of PA-treated participants (P = 0.275). Direct-on-blood PCR nucleic acid lateral flow immunoassay detected residual parasites at day 7 in 33.3% (23/69) and 30.3% (23/76) of AL and PA-treated participants, respectively (P = 0.692). qPCR-determined parasitemia at day 7 was associated with increased prevalence and density of gametocytes at baseline (P = 0.014 and P = 0.003, for prevalence and density, respectively) and during follow-up (P = 0.007 and P = 0.011, respectively, at day 7). A positive db-PCR-NALFIA outcome at day 7 was associated with treatment failure (odds ratio [OR]: 3.410, 95% confidence interval [CI]: 1.513-7.689, P = 0.003), but this association was not found for qPCR (OR: 0.701, 95% CI: 0.312-1.578, P = 0.391). Both qPCR and db-PCR-NALFIA detected substantial residual submicroscopic parasitemia after microscopically successful PA and AL treatment and can be useful tools to monitor parasite clearance. To predict treatment outcome, db-PCR-NALFIA may be more suitable than qPCR.
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Affiliation(s)
- Johanna M Roth
- Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Patrick Sawa
- Human Health Division, International Centre of Insect Physiology and Ecology, Mbita Point, Kenya
| | - George Omweri
- Human Health Division, International Centre of Insect Physiology and Ecology, Mbita Point, Kenya
| | - Nicodemus Makio
- Human Health Division, International Centre of Insect Physiology and Ecology, Mbita Point, Kenya
| | - Victor Osoti
- Human Health Division, International Centre of Insect Physiology and Ecology, Mbita Point, Kenya
| | - Menno D de Jong
- Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Henk D F H Schallig
- Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Pètra F Mens
- Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands
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27
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Feleke SM, Brhane BG, Mamo H, Assefa A, Woyessa A, Ogawa GM, Cama V. Sero-identification of the aetiologies of human malaria exposure (Plasmodium spp.) in the Limu Kossa District of Jimma Zone, South western Ethiopia. Malar J 2019; 18:292. [PMID: 31455373 PMCID: PMC6712699 DOI: 10.1186/s12936-019-2927-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 08/20/2019] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Malaria remains a very important public health problem in Ethiopia. Currently, only Plasmodium falciparum and Plasmodium vivax are considered in the malaria diagnostic and treatment policies. However, the existence and prevalence of Plasmodium ovale spp. and Plasmodium malariae in Ethiopia have not been extensively investigated. The objective of this study was to use a multiplex IgG antibody detection assay to evaluate evidence for exposure to any of these four human malaria parasites among asymptomatic individuals. METHODS Dried blood spots (DBS) were collected from 180 healthy study participants during a 2016 onchocerciasis survey in the Jimma Zone, southwest Ethiopia. IgG antibody reactivity was detected using a multiplex bead assay for seven Plasmodium antigens: P. falciparum circumsporozoite protein (CSP), P. falciparum apical membrane antigen-1 (AMA1), P. falciparum liver stage antigen-1 (LSA1), and homologs of the merozoite surface protein-1 (MSP1)-19kD antigens that are specific for P. falciparum, P. vivax, P. ovale spp. and P. malariae. RESULTS One hundred six participants (59%) were IgG seropositive for at least one of the Plasmodium antigens tested. The most frequent responses were against P. falciparum AMA1 (59, 33%) and P. vivax (55, 28%). However, IgG antibodies against P. ovale spp. and P. malariae were detected in 19 (11%) and 13 (7%) of the participants, respectively, providing serological evidence that P. malariae and P. ovale spp., which are rarely reported, may also be endemic in Jimma. CONCLUSION The findings highlight the informative value of multiplex serology and the need to confirm whether P. malariae and P. ovale spp. are aetiologies of malaria in Ethiopia, which is critical for proper diagnosis and treatment.
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Affiliation(s)
| | | | - Hassen Mamo
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Ashenafi Assefa
- Ethiopian Public Health Institute (EPHI), Addis Ababa, Ethiopia
| | - Adugna Woyessa
- Ethiopian Public Health Institute (EPHI), Addis Ababa, Ethiopia
| | - Guilherme Maerschner Ogawa
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Vitaliano Cama
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
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28
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Woldearegai TG, Lalremruata A, Nguyen TT, Gmeiner M, Veletzky L, Tazemda-Kuitsouc GB, Matsiegui PB, Mordmüller B, Held J. Characterization of Plasmodium infections among inhabitants of rural areas in Gabon. Sci Rep 2019; 9:9784. [PMID: 31278305 PMCID: PMC6611864 DOI: 10.1038/s41598-019-46194-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/25/2019] [Indexed: 12/18/2022] Open
Abstract
Plasmodium infections in endemic areas are often asymptomatic, can be caused by different species and contribute significantly to transmission. We performed a cross-sectional study in February/March 2016 including 840 individuals ≥ 1 year living in rural Gabon (Ngounié and Moyen-Ogooué). Plasmodium parasitemia was measured by high-sensitive, real-time quantitative PCR. In a randomly chosen subset of P. falciparum infections, gametocyte carriage and prevalence of chloroquine-resistant genotypes were analysed. 618/834 (74%) individuals were positive for Plasmodium 18S-rRNA gene amplification, of these 553 (66.3%) carried P. falciparum, 193 (23%) P. malariae, 74 (8.9%) P. ovale curtisi and 38 (4.6%) P.ovale wallikeri. Non-falciparum infections mostly presented as mixed infections. P. malariae monoinfected individuals were significantly older (median age: 60 years) than coinfected (20 years) or P. falciparum monoinfected individuals (23 years). P. falciparum gametocyte carriage was confirmed in 109/223 (48.9%) individuals, prevalence of chloroquine-resistant genotypes was high (298/336, 89%), including four infections with a new SVMNK genotype. In rural Gabon, Plasmodium infections with all endemic species are frequent, emphasizing that malaria control efforts shall cover asymptomatic infections also including non-falciparum infections when aiming for eradication.
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Affiliation(s)
- Tamirat Gebru Woldearegai
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen, Germany.,German Centre for Infection Research, partner site Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Albert Lalremruata
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen, Germany.,German Centre for Infection Research, partner site Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - The Trong Nguyen
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen, Germany.,German Centre for Infection Research, partner site Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,Vietnamese - German Center of Excellence in Medical Research, Hanoi, Vietnam
| | - Markus Gmeiner
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen, Germany.,German Centre for Infection Research, partner site Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Luzia Veletzky
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Pierre Blaise Matsiegui
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.,Centre de Recherches Médicales de la Ngounié, Fougamou, Gabon
| | - Benjamin Mordmüller
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen, Germany.,German Centre for Infection Research, partner site Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Jana Held
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen, Germany. .,German Centre for Infection Research, partner site Tübingen, Tübingen, Germany. .,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon.
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29
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Yman V, Wandell G, Mutemi DD, Miglar A, Asghar M, Hammar U, Karlsson M, Lind I, Nordfjell C, Rooth I, Ngasala B, Homann MV, Färnert A. Persistent transmission of Plasmodium malariae and Plasmodium ovale species in an area of declining Plasmodium falciparum transmission in eastern Tanzania. PLoS Negl Trop Dis 2019; 13:e0007414. [PMID: 31136585 PMCID: PMC6555537 DOI: 10.1371/journal.pntd.0007414] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 06/07/2019] [Accepted: 04/26/2019] [Indexed: 11/18/2022] Open
Abstract
A reduction in the global burden of malaria over the past two decades has encouraged efforts for regional malaria elimination. Despite the need to target all Plasmodium species, current focus is mainly directed towards Plasmodium falciparum, and to a lesser extent P. vivax. There is a substantial lack of data on both global and local transmission patterns of the neglected malaria parasites P. malariae and P. ovale spp. We used a species-specific real-time PCR assay targeting the Plasmodium 18s rRNA gene to evaluate temporal trends in the prevalence of all human malaria parasites over a 22-year period in a rural village in Tanzania.We tested 2897 blood samples collected in five cross-sectional surveys conducted between 1994 and 2016. Infections with P. falciparum, P. malariae, and P. ovale spp. were detected throughout the study period, while P. vivax was not detected. Between 1994 and 2010, we found a more than 90% reduction in the odds of infection with all detected species. The odds of P. falciparum infection was further reduced in 2016, while the odds of P. malariae and P. ovale spp. infection increased 2- and 6-fold, respectively, compared to 2010. In 2016, non-falciparum species occurred more often as mono-infections. The results demonstrate the persistent transmission of P. ovale spp., and to a lesser extent P. malariae despite a continued decline in P. falciparum transmission. This illustrates that the transmission patterns of the non-falciparum species do not necessarily follow those of P. falciparum, stressing the need for attention towards non-falciparum malaria in Africa. Malaria elimination will require a better understanding of the epidemiology of P. malariae and P. ovale spp. and improved tools for monitoring the transmission of all Plasmodium species, with a particular focus towards identifying asymptomatic carriers of infection and designing appropriate interventions to enhance malaria control. The reduction in the global burden of malaria has encouraged efforts for elimination. Attempts to control and monitor transmission have mainly focused on the predominant malaria parasites Plasmodium falciparum and P. vivax. However, eliminating malaria requires the elimination of all human malaria parasites and limited interest has been directed towards estimating the disease burden attributable to the neglected malaria parasites P. ovale spp. and P. malariae. The authors used molecular methods to analyse 2897 blood samples collected in five cross-sectional surveys over a period of 22 years, and described the transmission patterns of all human malaria parasites in a Tanzanian village. They demonstrate a persistent transmission of P. malariae and P. ovale spp. despite a substantial reduction in transmission of P. falciparum, highlighting the need for more attention towards non-falciparum malaria. The authors discuss the implications of these findings in the context of current efforts for regional malaria elimination.
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Affiliation(s)
- Victor Yman
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Grace Wandell
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Otolaryngology, University of Washington Medical Center, Seattle, Washington, United States of America
| | - Doreen D Mutemi
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Parasitology and Medical Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Aurelie Miglar
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Muhammad Asghar
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Ulf Hammar
- Unit of Biostatistics, Department of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Mattias Karlsson
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Ingrid Lind
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Cleis Nordfjell
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Ingegerd Rooth
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Billy Ngasala
- Department of Parasitology and Medical Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania.,Department of Women's and Children's Health, International Maternal and Child Health (IMCH), Uppsala University, Uppsala, Sweden
| | - Manijeh Vafa Homann
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Anna Färnert
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
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Grande R, Antinori S, Meroni L, Menegon M, Severini C. A case of Plasmodium malariae recurrence: recrudescence or reinfection? Malar J 2019; 18:169. [PMID: 31088460 PMCID: PMC6515619 DOI: 10.1186/s12936-019-2806-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 05/07/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Plasmodium malariae is the most neglected of the six human malaria species and it is still unknown which is the mechanism underlying the long latency of this Plasmodium. CASE PRESENTATION A case of PCR-confirmed P. malariae recurrence in a 52-year old Italian man was observed 5 months after a primary attack. In the interval between the two observed episodes of malaria the patient denied any further stay in endemic areas except for a visit to Libya, a country considered malaria-free. Genomic DNA of the P. malariae strain using five microsatellites (PM2, PM9, PM11, PM25, PM34) and the antigen marker of circumsporozoite (csp) was amplified and sequenced. Analysis of polymorphisms of the P. malariae csp central repeat region showed differences between the strains responsible of the first and second episode of malaria. A difference in the allele size was also observed for the sequence analysis of PM2 microsatellites. CONCLUSIONS Plasmodium malariae is a challenging human malaria parasite and even with the use of molecular techniques the pathogenesis of recurrent episodes cannot be precisely explained.
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Affiliation(s)
- Romualdo Grande
- Clinical Microbiology, Virology and Bioemergency, ASST Fatebenefratelli Sacco, Luigi Sacco Hospital, Milan, Italy
| | - Spinello Antinori
- Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Milan, Italy.
- III Division of Infectious Diseases, ASST Fatebenefratelli Sacco, Luigi Sacco Hospital, Milan, Italy.
| | - Luca Meroni
- III Division of Infectious Diseases, ASST Fatebenefratelli Sacco, Luigi Sacco Hospital, Milan, Italy
| | - Michela Menegon
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Carlo Severini
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
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Al-Shehri H, Power BJ, Archer J, Cousins A, Atuhaire A, Adriko M, Arinaitwe M, Alanazi AD, LaCourse EJ, Kabatereine NB, Stothard JR. Non-invasive surveillance of Plasmodium infection by real-time PCR analysis of ethanol preserved faeces from Ugandan school children with intestinal schistosomiasis. Malar J 2019; 18:109. [PMID: 30935388 PMCID: PMC6444585 DOI: 10.1186/s12936-019-2748-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 03/26/2019] [Indexed: 12/22/2022] Open
Abstract
Background As part of ongoing co-surveillance of intestinal schistosomiasis and malaria in Ugandan school children, a non-invasive detection method for amplification of Plasmodium DNA using real-time (rt)PCR analysis of ethanol preserved faeces (EPF) was assessed. For diagnostic tabulations, results were compared to rtPCR analysis of dried blood spots (DBS) and field-based point-of-care (POC) rapid diagnostic tests (RDTs). Methods A total of 247 school children from 5 primary schools along the shoreline of Lake Albert were examined with matched EPF and DBS obtained. Mean prevalence and prevalence by school was calculated by detection of Plasmodium DNA by rtPCR using a 18S rDNA Taqman® probe. Diagnostic sensitivity, specificity, positive and negative predictive values were tabulated and compared against RDTs. Results By rtPCR of EPF and DBS, 158 (63.9%; 95% CI 57.8–69.7) and 198 (80.1%, 95% CI 74.7–84.6) children were positive for Plasmodium spp. By RDT, 138 (55.8%; 95% CI 49.6–61.9) and 45 (18.2%; 95% CI 13.9–23.5) children were positive for Plasmodium falciparum, and with non-P. falciparum co-infections, respectively. Using RDT results as a convenient field-based reference, the sensitivity of rtPCR of EPF and DBS was 73.1% (95% CI 65.2–79.8) and 94.2% (95% CI 88.9–97.0) while specificity was 47.7% (95% CI 38.5–57.0) and 37.6% (95% CI 29.0–46.9), respectively. With one exception, school prevalence estimated by analysis of EPF was higher than that by RDT. Positive and negative predictive values were compared and discussed. Conclusions In this high transmission setting, EPF sampling with rtPCR analysis has satisfactory diagnostic performance in estimation of mean prevalence and prevalence by school upon direct comparison with POC-RDTs. Although analysis of EPF was judged inferior to that of DBS, it permits an alternative non-invasive sampling regime that could be implemented alongside general monitoring and surveillance for other faecal parasites. EPF analysis may also have future value in passive surveillance of low transmission settings.
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Affiliation(s)
- Hajri Al-Shehri
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK.,Ministry of Health, Asir District, Abha, Kingdom of Saudi Arabia
| | - B Joanne Power
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Sir Graeme Davies Building, 120 University Place, Glasgow, G12 8TA, UK
| | - John Archer
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Alice Cousins
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Aaron Atuhaire
- Vector Control Division, Ministry of Health, Kampala, Uganda
| | - Moses Adriko
- Vector Control Division, Ministry of Health, Kampala, Uganda
| | - Moses Arinaitwe
- Vector Control Division, Ministry of Health, Kampala, Uganda
| | - Abdullah D Alanazi
- Department of Biological Science, Faculty of Science and Humanities, Shaqra University, Ad-Dawadimi, Saudi Arabia
| | - E James LaCourse
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | | | - J Russell Stothard
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK.
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Betson M, Clifford S, Stanton M, Kabatereine NB, Stothard JR. Emergence of Nonfalciparum Plasmodium Infection Despite Regular Artemisinin Combination Therapy in an 18-Month Longitudinal Study of Ugandan Children and Their Mothers. J Infect Dis 2018; 217:1099-1109. [PMID: 29325068 PMCID: PMC5939692 DOI: 10.1093/infdis/jix686] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 01/05/2018] [Indexed: 12/04/2022] Open
Abstract
As part of a longitudinal cohort investigation of intestinal schistosomiasis and malaria in Ugandan children and their mothers on the shorelines of Lakes Victoria and Albert, we documented risk factors and morbidity associated with nonfalciparum Plasmodium infections and the longitudinal dynamics of Plasmodium species in children. Host age, household location, and Plasmodium falciparum infection were strongly associated with nonfalciparum Plasmodium infections, and Plasmodium malariae infection was associated with splenomegaly. Despite regular artemisinin combination therapy treatment, there was a 3-fold rise in P. malariae prevalence, which was not accountable for by increasing age of the child. Worryingly, our findings reveal the consistent emergence of nonfalciparum infections in children, highlighting the complex dynamics underlying multispecies infections here. Given the growing body of evidence that nonfalciparum malaria infections cause significant morbidity, we encourage better surveillance for nonfalciparum Plasmodium infections, particularly in children, with more sensitive DNA detection methods and improved field-based diagnostics.
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Affiliation(s)
- Martha Betson
- School of Veterinary Medicine, University of Surrey, Guildford
| | - Sarah Clifford
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Michelle Stanton
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - J Russell Stothard
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Zhang X, Yao L, Sun J, Pan J, Chen H, Zhang L, Ruan W. Malaria in Southeastern China from 2012 to 2016: Analysis of Imported Cases. Am J Trop Med Hyg 2018; 98:1107-1112. [PMID: 29488463 PMCID: PMC5928818 DOI: 10.4269/ajtmh.17-0476] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
To study the epidemiological distribution and the incident trends of imported malaria from 2012 to 2016 in Zhejiang Province, southeastern China, we collected data on malaria from the Information System for Parasitic Disease Control and Prevention. A total of 1,003 malaria cases were reported during 2012–2016, and all of these cases were imported. Plasmodium falciparum was the predominant species (76.3%) in Zhejiang Province. The percentage of Plasmodium vivax decreased from 33.6% to 8.1%, whereas the percentage of Plasmodium ovale and Plasmodium malariae increased. Most cases were male (89.8%), mostly in the age group of 21–50 years (82.6%). Businessmen (33.0%), workers (21.0%), farmers (18.8%), and overseas laborers (11.7%) were at high risk. The origin of the largest number of imported cases was Africa (89.5%), followed by Asia (10.0%) and Oceania (0.5%). The time interval from illness onset to confirmation was found to be significantly associated with the complications of patients. Out of 3,461 febrile individuals tested during reactive case detection, 10 malaria-positive individuals were identified. Effective surveillance and response system should be strengthened to prevent the reintroduction of malaria.
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Affiliation(s)
- Xuan Zhang
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
| | - Linong Yao
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
| | - Jimin Sun
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
| | - Jinren Pan
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
| | - Hualiang Chen
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
| | - Lingling Zhang
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
| | - Wei Ruan
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, PR China
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34
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Doritchamou JYA, Akuffo RA, Moussiliou A, Luty AJF, Massougbodji A, Deloron P, Tuikue Ndam NG. Submicroscopic placental infection by non-falciparum Plasmodium spp. PLoS Negl Trop Dis 2018; 12:e0006279. [PMID: 29432484 PMCID: PMC5825172 DOI: 10.1371/journal.pntd.0006279] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 02/23/2018] [Accepted: 01/29/2018] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Among the Plasmodium species that infect humans, adverse effects of P. falciparum and P. vivax have been extensively studied and reported with respect to poor outcomes particularly in first time mothers and in pregnant women living in areas with unstable malaria transmission. Although, other non-falciparum malaria infections during pregnancy have sometimes been reported, little is known about the dynamics of these infections during pregnancy. METHODS AND FINDINGS Using a quantitative PCR approach, blood samples collected from Beninese pregnant women during the first antenatal visit (ANV) and at delivery including placental blood were screened for Plasmodium spp. Risk factors associated with Plasmodium spp. infection during pregnancy were assessed as well as the relationships with pregnancy outcomes. P. falciparum was the most prevalent Plasmodium species detected during pregnancy, irrespective either of parity, of age or of season during which the infection occurred. Although no P. vivax infections were detected in this cohort, P. malariae (9.2%) and P. ovale (5.8%) infections were observed in samples collected during the first ANV. These non-falciparum infections were also detected in maternal peripheral blood (1.3% for P. malariae and 1.2% for P. ovale) at delivery. Importantly, higher prevalence of P. malariae (5.5%) was observed in placental than peripheral blood while that of P. ovale was similar (1.8% in placental blood). Among the non-falciparum infected pregnant women with paired peripheral and placental samples, P. malariae infections in the placental blood was significantly higher than in the peripheral blood, suggesting a possible affinity of P. malariae for the placenta. However, no assoctiation of non-falciparum infections and the pregnancy outcomes was observed. CONCLUSIONS Overall this study provided insights into the molecular epidemiology of Plasmodium spp. infection during pregnancy, indicating placental infection by non-falciparum Plasmodium and the lack of association of these infections with adverse pregnancy outcomes.
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Affiliation(s)
- Justin Y. A. Doritchamou
- MERIT, Intitut de Recherche pour le Developpement—Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
| | - Richard A. Akuffo
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Azizath Moussiliou
- MERIT, Intitut de Recherche pour le Developpement—Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
| | - Adrian J. F. Luty
- MERIT, Intitut de Recherche pour le Developpement—Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
| | - Achille Massougbodji
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
| | - Philippe Deloron
- MERIT, Intitut de Recherche pour le Developpement—Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Nicaise G. Tuikue Ndam
- MERIT, Intitut de Recherche pour le Developpement—Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- * E-mail:
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35
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Huggan PJ, Ng CH, Ho J, Lin RTPV, Chavatte JM. A case of blackwater fever with persistent Plasmodium falciparum parasitaemia detected by PCR after artemether-lumefantrine treatment. Malar J 2018; 17:35. [PMID: 29338726 PMCID: PMC5771159 DOI: 10.1186/s12936-018-2180-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Accepted: 01/10/2018] [Indexed: 11/21/2022] Open
Abstract
Background Blackwater fever is a complication of malaria infection consisting of a syndrome of febrile intra-vascular haemolysis with severe anaemia and intermittent passage of dark-red to black colour urine. Despite numerous reports and studies of this condition, its pathogenesis remains incompletely understood. Case presentation This report describes a case of classic blackwater fever in a returning traveller, without prior history of malaria infection nor usage of anti-malarial prophylaxis, treated with two courses of oral artemether–lumefantrine combination therapy. Unusual persistence of submicroscopic Plasmodium falciparum parasitaemia was detected by PCR for 18 days after initiation of treatment. Conclusion To the authors’ knowledge this is the first reported occurrence of a case of blackwater fever associated with prolonged submicroscopic parasitaemia. This unusual case challenges the current knowledge of the pathogenesis of this condition and opens questions that may have important diagnostic and treatment implications. Electronic supplementary material The online version of this article (10.1186/s12936-018-2180-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Paul John Huggan
- Waikato Hospital, Hamilton, New Zealand.,Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Chin Hin Ng
- Department of Haematology-Oncology, National University Cancer Institute, National University Health System, Singapore, Singapore
| | - Jennifer Ho
- Woolcock Institute of Medical Research, Glebe, Sydney, NSW, 2037, Australia.,South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Raymond Tzer Pin Valentine Lin
- Malaria Reference Centre, National Public Health Laboratory, Ministry of Health, Singapore, 3 Biopolis Drive, Synapse #05-14/16, Singapore, 138623, Singapore.,Department of Laboratory Medicine, National University Hospital, Singapore, Singapore.,Departments of Microbiology and Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Jean-Marc Chavatte
- Malaria Reference Centre, National Public Health Laboratory, Ministry of Health, Singapore, 3 Biopolis Drive, Synapse #05-14/16, Singapore, 138623, Singapore.
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Roh ME, Oyet C, Orikiriza P, Wade M, Kiwanuka GN, Mwanga-Amumpaire J, Parikh S, Boum Y. Asymptomatic Plasmodium Infections in Children in Low Malaria Transmission Setting, Southwestern Uganda(1). Emerg Infect Dis 2018; 22:1494-8. [PMID: 27434741 PMCID: PMC4982177 DOI: 10.3201/eid2208.160619] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A survey of asymptomatic children in Uganda showed Plasmodium malariae and P. falciparum parasites in 45% and 55% of microscopy-positive samples, respectively. Although 36% of microscopy-positive samples were negative by rapid diagnostic test, 75% showed P. malariae or P. ovale parasites by PCR, indicating that routine diagnostic testing misses many non-P. falciparum malarial infections.
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Asua V, Tukwasibwe S, Conrad M, Walakira A, Nankabirwa JI, Mugenyi L, Kamya MR, Nsobya SL, Rosenthal PJ. Plasmodium Species Infecting Children Presenting with Malaria in Uganda. Am J Trop Med Hyg 2017; 97:753-757. [PMID: 28990911 DOI: 10.4269/ajtmh.17-0345] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Contributions of species other than Plasmodium falciparum to human malaria in sub-Saharan Africa are uncertain. We collected blood from children aged 6 months to 10 years diagnosed with malaria by Giemsa-stained blood smears (176 subjects) or histidine rich protein-2-based rapid diagnostic tests (323 subjects) in 2016; 50 samples from each of 10 sites across Uganda were studied to identify infecting species. Of 499 available samples, 474 demonstrated plasmodial infection by polymerase chain reaction amplification of 18S ribosomal RNA genes, including P. falciparum in 472, Plasmodium malariae in 22, Plasmodium ovale in 15, and Plasmodium vivax in four; 435 were pure P. falciparum, two did not contain P. falciparum, and the remainder were mixed infections including P. falciparum. The prevalence of nonfalciparum species varied geographically. Stratifying based on recent history of indoor residual spraying (IRS) of insecticides, nonfalciparum infections were seen in 27/189 (14.8%) samples from sites that received and 13/285 (4.6%) samples from sites that did not receive IRS since 2010 (P = 0.0013). Overall, 39/474 (8.2%) samples from individuals diagnosed with malaria included nonfalciparum infections. Thus, a substantial proportion of episodes of malaria in Uganda include infections with plasmodial species other than P. falciparum.
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Affiliation(s)
- Victor Asua
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Melissa Conrad
- Department of Medicine, University of California, San Francisco, San Francisco, California; 3Department of Medicine, Makerere University, Kampala, Uganda
| | | | - Joaniter I Nankabirwa
- Deparment of Pathology, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Moses R Kamya
- Deparment of Pathology, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Samuel L Nsobya
- Deparment of Pathology, Makerere University, Kampala, Uganda.,Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Philip J Rosenthal
- Department of Medicine, University of California, San Francisco, San Francisco, California; 3Department of Medicine, Makerere University, Kampala, Uganda
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Rutledge GG, Marr I, Huang GKL, Auburn S, Marfurt J, Sanders M, White NJ, Berriman M, Newbold CI, Anstey NM, Otto TD, Price RN. Genomic Characterization of Recrudescent Plasmodium malariae after Treatment with Artemether/Lumefantrine. Emerg Infect Dis 2017; 23:1300-1307. [PMID: 28430103 PMCID: PMC5547787 DOI: 10.3201/eid2308.161582] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Plasmodium malariae is the only human malaria parasite species with a 72-hour intraerythrocytic cycle and the ability to persist in the host for life. We present a case of a P. malariae infection with clinical recrudescence after directly observed administration of artemether/lumefantrine. By using whole-genome sequencing, we show that the initial infection was polyclonal and the recrudescent isolate was a single clone present at low density in the initial infection. Haplotypic analysis of the clones in the initial infection revealed that they were all closely related and were presumably recombinant progeny originating from the same infective mosquito bite. We review possible explanations for the P. malariae treatment failure and conclude that a 3-day artemether/lumefantrine regimen is suboptimal for this species because of its long asexual life cycle.
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A preface on advances in diagnostics for infectious and parasitic diseases: detecting parasites of medical and veterinary importance. Parasitology 2017; 141:1781-8. [PMID: 25415359 DOI: 10.1017/s0031182014001309] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
There are many reasons why detection of parasites of medical and veterinary importance is vital and where novel diagnostic and surveillance tools are required. From a medical perspective alone, these originate from a desire for better clinical management and rational use of medications. Diagnosis can be at the individual-level, at close to patient settings in testing a clinical suspicion or at the community-level, perhaps in front of a computer screen, in classification of endemic areas and devising appropriate control interventions. Thus diagnostics for parasitic diseases has a broad remit as parasites are not only tied with their definitive hosts but also in some cases with their vectors/intermediate hosts. Application of current diagnostic tools and decision algorithms in sustaining control programmes, or in elimination settings, can be problematic and even ill-fitting. For example in resource-limited settings, are current diagnostic tools sufficiently robust for operational use at scale or are they confounded by on-the-ground realities; are the diagnostic algorithms underlying public health interventions always understood and well-received within communities which are targeted for control? Within this Special Issue (SI) covering a variety of diseases and diagnostic settings some answers are forthcoming. An important theme, however, throughout the SI is to acknowledge that cross-talk and continuous feedback between development and application of diagnostic tests is crucial if they are to be used effectively and appropriately.
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40
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Non-falciparum malaria in Dakar: a confirmed case of Plasmodium ovale wallikeri infection. Malar J 2016; 15:429. [PMID: 27557982 PMCID: PMC4997729 DOI: 10.1186/s12936-016-1485-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 08/11/2016] [Indexed: 11/15/2022] Open
Abstract
Background Plasmodium ovale is rarely described in Senegal. A case of clinical malaria due to P. ovale wallikeri in West Central of Senegal is reported. Case A 34-year-old male baker in Dakar, with no significant previous medical history, was admitted to a health clinic with fever and vomiting. Fever had been lasting for 4 days with peaks every 48 h. As monospecific Plasmodium falciparum HRP-2 RDT was negative, he was treated with antibiotics. However, owing to persisting symptoms, he was referred to the emergency unit of the Youssou Mbargane Diop Hospital, Dakar, Senegal. Clinical examination found impaired general condition. All other physical examinations were normal. Laboratory tests showed anaemia (haemoglobin 11.4 g/dl), severe thrombocytopaenia (platelets 30 × 109/mm3), leukopenia (3650/mm3), lymphocytopenia (650/mm3). Renal function was normal as indicated by creatininaemia and uraemia (11 mg/l and 0.25 g/l, respectively) and liver enzymes were slightly elevated (aspartate aminotransferase 77 UI/l and alanine aminotransferase 82 UI/l). Blood smear evaluations in Parasitology Laboratory of Aristide Le Dantec Hospital showed malaria parasites of the species P. ovale with a 0.08 % parasitaemia. Molecular confirmation was done by real time PCR targeting the 18S rRNA gene. The P. ovale infection was further analysed to species level targeting the potra gene and was identified as P. ovale wallikeri. According to the hospital’s malaria treatment guidelines for severe malaria, treatment consisted of intravenous quinine at hour 0 (start of treatment) and 24 h after initial treatment, followed by artemether–lumefantrine 24 h later. A negative microscopy was noted on day 3 post-treatment and the patient reported no further symptoms. Conclusion Malaria due to non-falciparum species is probably underestimated in Senegal. RDTs specific to non-falciparum species and/or pan specific RDTs should be included as tools of diagnosis to fight against malaria in Senegal. In addition, a field-deployable molecular tool such as the loop-mediated isothermal amplification can be considered as an additional useful tool to detect low malaria parasite infections and for speciation. In addition, national malaria control policies should consider other non-falciparum species in treatment guidelines, including the provision of primaquine for the treatment of relapsing parasites.
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Sutherland CJ. Persistent Parasitism: The Adaptive Biology of Malariae and Ovale Malaria. Trends Parasitol 2016; 32:808-819. [PMID: 27480365 DOI: 10.1016/j.pt.2016.07.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/17/2016] [Accepted: 07/12/2016] [Indexed: 12/29/2022]
Abstract
Plasmodium malariae causes malaria in humans throughout the tropics and subtropics. Plasmodium ovale curtisi and Plasmodium ovale wallikeri are sympatric sibling species common in sub-Saharan Africa and also found in Oceania and Asia. Although rarely identified as the cause of malaria cases in endemic countries, PCR detection has confirmed all three parasite species to be more prevalent, and persistent, than previously thought. Chronic, low-density, multispecies asymptomatic infection is a successful biological adaptation by these Plasmodium spp., a pattern also observed among malaria parasites of wild primates. Current whole-genome analyses are illuminating the species barrier separating the ovale parasite species and reveal substantial expansion of subtelomeric gene families. The evidence for and against a quiescent pre-erythrocytic form of P. malariae is reviewed.
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Affiliation(s)
- Colin J Sutherland
- Department of Immunology and Infection and Public Health England Malaria Reference Laboratory, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK; Department of Clinical Parasitology, Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, Mortimer Market Centre, Capper Street, London WC1E 6JB, UK.
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Chang HH, Meibalan E, Zelin J, Daniels R, Eziefula AC, Meyer EC, Tadesse F, Grignard L, Joice RC, Drakeley C, Wirth DF, Volkman SK, Buckee C, Bousema T, Marti M. Persistence of Plasmodium falciparum parasitemia after artemisinin combination therapy: evidence from a randomized trial in Uganda. Sci Rep 2016; 6:26330. [PMID: 27197604 PMCID: PMC4873826 DOI: 10.1038/srep26330] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 05/03/2016] [Indexed: 11/12/2022] Open
Abstract
Artemisinin resistance is rapidly spreading in Southeast Asia. The efficacy of artemisinin-combination therapy (ACT) continues to be excellent across Africa. We performed parasite transcriptional profiling and genotyping on samples from an antimalarial treatment trial in Uganda. We used qRT-PCR and genotyping to characterize residual circulating parasite populations after treatment with either ACT or ACT-primaquine. Transcripts suggestive of circulating ring stage parasites were present after treatment at a prevalence of >25% until at least 14 days post initiation of treatment. Greater than 98% of all ring stage parasites were cleared within the first 3 days, but subsequently persisted at low concentrations until day 14 after treatment. Genotyping demonstrated a significant decrease in multiplicity of infection within the first 2 days in both ACT and ACT-primaquine arms. However, multiple clone infections persisted until day 14 post treatment. Our data suggest the presence of genetically diverse persisting parasite populations after ACT treatment. Although we did not demonstrate clinical treatment failures after ACT and the viability and transmissibility of persisting ring stage parasites remain to be shown, these findings are of relevance for the interpretation of parasite clearance transmission dynamics and for monitoring drug effects in Plasmodium falciparum parasites.
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Affiliation(s)
- Hsiao-Han Chang
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
| | - Elamaran Meibalan
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
| | - Justin Zelin
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
| | - Rachel Daniels
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA.,Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA
| | - Alice C Eziefula
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Evan C Meyer
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
| | - Fitsum Tadesse
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Lynn Grignard
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Regina C Joice
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
| | - Chris Drakeley
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Dyann F Wirth
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA.,Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA
| | - Sarah K Volkman
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA.,Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA.,Simmons College, 300 Fenway, Boston, MA 02115, USA
| | - Caroline Buckee
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
| | - Teun Bousema
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,Institute for Molecular Life Sciences, Radboud University, Geert Grooteplain Zuid 28, 6525 GA Nijmegen, The Netherlands
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, 665 Huntington Ave, Boston, MA 02115, USA
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Chavatte JM, Tan SBH, Snounou G, Lin RTPV. Molecular characterization of misidentified Plasmodium ovale imported cases in Singapore. Malar J 2015; 14:454. [PMID: 26577930 PMCID: PMC4650842 DOI: 10.1186/s12936-015-0985-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/03/2015] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Plasmodium ovale, considered the rarest of the malaria parasites of humans, consists of two morphologically identical but genetically distinct sympatric species, Plasmodium ovale curtisi and Plasmodium ovale wallikeri. These parasites resemble morphologically to Plasmodium vivax with which they also share a tertian periodicity and the ability to cause relapses, making them easily misidentified as P. vivax. Plasmodium ovale infections are rarely reported, but given the likelihood of misidentification, their prevalence might be underestimated. METHODS Morphological and molecular analysis of confirmed malaria cases admitted in Singapore in 2012-2014 detected nine imported P. ovale cases that had been misidentified as P. vivax. Since P. ovale had not been previously officially reported in Singapore, a retrospective analysis of available, frozen, archival blood samples was performed and returned two additional misidentified P. ovale cases in 2003 and 2006. These eleven P. ovale samples were characterized with respect to seven molecular markers (ssrRNA, Potra, Porbp2, Pog3p, dhfr-ts, cytb, cox1) used in recent studies to distinguish between the two sympatric species, and to a further three genes (tufa, clpC and asl). RESULTS The morphological features of P. ovale and the differential diagnosis with P. vivax were reviewed and illustrated by microphotographs. The genetic dimorphism between P. ovale curtisi and P. ovale wallikeri was assessed by ten molecular markers distributed across the three genomes of the parasite (Genbank KP050361-KP050470). The data obtained for seven of these markers were compared with those published and confirmed that both P. ovale species were present. This dimorphism was also confirmed for the first time on: (1) two genes from the apicoplast genome (tufA and clpC genes); and, (2) the asl gene that was used for phylogenetic analyses of other Plasmodium species, and that was found to harbour the highest number of dimorphic loci between the two P. ovale species. CONCLUSION Misidentified P. ovale infections are reported for the first time among imported malaria cases in Singapore. Genetic dimorphism between P. ovale curtisi and P. ovale wallikeri was confirmed using markers from the parasites' three genomes. The apparent increase of imported P. ovale since 2012 (with yearly detection of cases) is puzzling. Given decrease in the overall number of malaria cases recorded in Singapore since 2010 the 'resurgence' of this neglected species raises public health concerns.
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Affiliation(s)
- Jean-Marc Chavatte
- Malaria Reference Centre - National Public Health Laboratory, Ministry of Health, Singapore, 3 Biopolis Drive, Synapse #05-14/16, 138623, Singapore, Singapore.
| | - Sarah Bee Hui Tan
- Malaria Reference Centre - National Public Health Laboratory, Ministry of Health, Singapore, 3 Biopolis Drive, Synapse #05-14/16, 138623, Singapore, Singapore.
| | - Georges Snounou
- Sorbonne Universités, UPMC Université Paris 06, UPMC UMRS CR7, 75005, Paris, France.
- Centre d'Immunologie et de Maladies Infectieuses (CIMI) Paris, Institut National de la Santé et de la Recherche Médicale (Inserm) U1135, Centre National de la Recherche Scientifique (CNRS) ERL 8255, 75013, Paris, France.
| | - Raymond Tzer Pin Valentine Lin
- Malaria Reference Centre - National Public Health Laboratory, Ministry of Health, Singapore, 3 Biopolis Drive, Synapse #05-14/16, 138623, Singapore, Singapore.
- Department of Laboratory Medicine, National University Hospital, 5 Lower Kent Ridge Road, 119074, Singapore, Singapore.
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Block MD4, Level 3, 117545, Singapore, Singapore.
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Teo BHY, Lansdell P, Smith V, Blaze M, Nolder D, Beshir KB, Chiodini PL, Cao J, Färnert A, Sutherland CJ. Delayed Onset of Symptoms and Atovaquone-Proguanil Chemoprophylaxis Breakthrough by Plasmodium malariae in the Absence of Mutation at Codon 268 of pmcytb. PLoS Negl Trop Dis 2015; 9:e0004068. [PMID: 26485258 PMCID: PMC4618945 DOI: 10.1371/journal.pntd.0004068] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 08/18/2015] [Indexed: 11/19/2022] Open
Abstract
Plasmodium malariae is widely distributed across the tropics, causing symptomatic malaria in humans with a 72-hour fever periodicity, and may present after latency periods lasting up to many decades. Delayed occurrence of symptoms is observed in humans using chemoprophylaxis, or patients having received therapies targeting P. falciparum intraerythrocytic asexual stages, but few investigators have addressed the biological basis of the ability of P. malariae to persist in the human host. To investigate these interesting features of P. malariae epidemiology, we assembled, here, an extensive case series of P. malariae malaria patients presenting in non-endemic China, Sweden, and the UK who returned from travel in endemic countries, mainly in Africa. Out of 378 evaluable P. malariae cases, 100 (26.2%) reported using at least partial chemoprophylaxis, resembling the pattern seen with the relapsing parasites P. ovale spp. and P. vivax. In contrast, for only 7.5% of imported UK cases of non-relapsing P. falciparum was any chemoprophylaxis use reported. Genotyping of parasites from six patients reporting use of atovaquone-proguanil chemoprophylaxis did not reveal mutations at codon 268 of the cytb locus of the P. malariae mitochondrial genome. While travellers with P. malariae malaria are significantly more likely to report prophylaxis use during endemic country travel than are those with P. falciparum infections, atovaquone-proguanil prophylaxis breakthrough was not associated with pmcytb mutations. These preliminary studies, together with consistent observations of the remarkable longevity of P. malariae, lead us to propose re-examination of the dogma that this species is not a relapsing parasite. Further studies are needed to investigate our favoured hypothesis, namely that P. malariae can initiate a latent hypnozoite developmental programme in the human hepatocyte: if validated this will explain the consistent observations of remarkable longevity of parasitism, even in the presence of antimalarial prophylaxis or treatment.
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Affiliation(s)
- Beatrix Huei-Yi Teo
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Paul Lansdell
- Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Valerie Smith
- Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Marie Blaze
- Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Debbie Nolder
- Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Khalid B. Beshir
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Peter L. Chiodini
- Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Department of Clinical Parasitology, Hospital for Tropical Diseases, London, United Kingdom
| | - Jun Cao
- Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Anna Färnert
- Dept Medicine Solna, Karolinska Institutet, Stockholm, Sweden
- Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Colin J. Sutherland
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Department of Clinical Parasitology, Hospital for Tropical Diseases, London, United Kingdom
- * E-mail: ;
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Cook J, Xu W, Msellem M, Vonk M, Bergström B, Gosling R, Al-Mafazy AW, McElroy P, Molteni F, Abass AK, Garimo I, Ramsan M, Ali A, Mårtensson A, Björkman A. Mass screening and treatment on the basis of results of a Plasmodium falciparum-specific rapid diagnostic test did not reduce malaria incidence in Zanzibar. J Infect Dis 2015; 211:1476-83. [PMID: 25429102 PMCID: PMC10881232 DOI: 10.1093/infdis/jiu655] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 11/10/2014] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND Seasonal increases in malaria continue in hot spots in Zanzibar. Mass screening and treatment (MSAT) may help reduce the reservoir of infection; however, it is unclear whether rapid diagnostic tests (RDTs) detect a sufficient proportion of low-density infections to influence subsequent transmission. METHODS Two rounds of MSAT using Plasmodium falciparum-specific RDT were conducted in 5 hot spots (population, 12 000) in Zanzibar in 2012. In parallel, blood samples were collected on filter paper for polymerase chain reaction (PCR) analyses. Data on confirmed malarial parasite infections from health facilities in intervention and hot spot control areas were monitored as proxy for malaria transmission. RESULTS Approximately 64% of the population (7859) were screened at least once. P. falciparum prevalence, as measured by RDT, was 0.2% (95% confidence interval [CI], .1%-.3%) in both rounds, compared with PCR measured prevalences (for all species) of 2.5% (95% CI, 2.1%-2.9%) and 3.8% (95% CI, 3.2%-4.4%) in rounds 1 and 2, respectively. Two fifths (40%) of infections detected by PCR included non-falciparum species. Treatment of RDT-positive individuals (4% of the PCR-detected parasite carriers) did not reduce subsequent malaria incidence, compared with control areas. CONCLUSIONS Highly sensitive point-of-care diagnostic tools for detection of all human malaria species are needed to make MSAT an effective strategy in settings where malaria elimination programs are in the pre-elimination phase.
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Affiliation(s)
- Jackie Cook
- Department of Microbiology and Tumor and Cell Biology, Uppsala University, Sweden
| | - Weiping Xu
- Department of Microbiology and Tumor and Cell Biology, Uppsala University, Sweden
| | - Mwinyi Msellem
- Zanzibar Malaria Elimination Programme, Ministry of Health, University of California–San Francisco
| | - Marlotte Vonk
- Department of Microbiology and Tumor and Cell Biology, Uppsala University, Sweden
| | - Beatrice Bergström
- Department of Microbiology and Tumor and Cell Biology, Uppsala University, Sweden
| | - Roly Gosling
- Global Health Group, University of California–San Francisco
| | - Abdul-Wahid Al-Mafazy
- Zanzibar Malaria Elimination Programme, Ministry of Health, University of California–San Francisco
| | - Peter McElroy
- US President’s Malaria Initiative and Centers for Disease Control and Prevention Tanzania, University of California–San Francisco
- Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Fabrizio Molteni
- Swiss Tropical and Public Health Institute, University of California–San Francisco
- University of Basel, Switzerland
| | - Ali K. Abass
- Zanzibar Malaria Elimination Programme, Ministry of Health, University of California–San Francisco
| | - Issa Garimo
- RTI International, Dar es Salaam, Tanzania, University of California–San Francisco
| | - Mahdi Ramsan
- RTI International, Dar es Salaam, Tanzania, University of California–San Francisco
| | - Abdullah Ali
- Zanzibar Malaria Elimination Programme, Ministry of Health, University of California–San Francisco
| | - Andreas Mårtensson
- Department of Microbiology and Tumor and Cell Biology, Uppsala University, Sweden
- Global Health, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Uppsala University, Sweden
- Centre for Clinical Research Sörmland, Uppsala University, Sweden
| | - Anders Björkman
- Department of Microbiology and Tumor and Cell Biology, Uppsala University, Sweden
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Characterization of Plasmodium ovale curtisi and P. ovale wallikeri in Western Kenya utilizing a novel species-specific real-time PCR assay. PLoS Negl Trop Dis 2015; 9:e0003469. [PMID: 25590587 PMCID: PMC4295880 DOI: 10.1371/journal.pntd.0003469] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 12/11/2014] [Indexed: 11/19/2022] Open
Abstract
Background Plasmodium ovale is comprised of two genetically distinct subspecies, P. ovale curtisi and P. ovale wallikeri. Although P. ovale subspecies are similar based on morphology and geographical distribution, allelic differences indicate that P. ovale curtisi and P. ovale wallikeri are genetically divergent. Additionally, potential clinical and latency duration differences between P. ovale curtisi and P. ovale wallikeri demonstrate the need for investigation into the contribution of this neglected malaria parasite to the global malaria burden. Methods In order to detect all P. ovale subspecies simultaneously, we developed an inclusive P. ovale-specific real-time PCR assay based on conserved regions between P. ovale curtisi and P. ovale wallikeri in the reticulocyte binding protein 2 (rbp2) gene. Additionally, we characterized the P. ovale subspecies prevalence from 22 asymptomatic malaria infections using multilocus genotyping to discriminate P. ovale curtisi and P. ovale wallikeri. Results Our P. ovale rbp2 qPCR assay validation experiments demonstrated a linear dynamic range from 6.25 rbp2 plasmid copies/microliter to 100,000 rbp2 plasmid copies/microliter and a limit of detection of 1.5 rbp2 plasmid copies/microliter. Specificity experiments showed the ability of the rbp2 qPCR assay to detect low-levels of P. ovale in the presence of additional malaria parasite species, including P. falciparum, P. vivax, and P. malariae. We identified P. ovale curtisi and P. ovale wallikeri in Western Kenya by DNA sequencing of the tryptophan-rich antigen gene, the small subunit ribosomal RNA gene, and the rbp2 gene. Conclusions Our novel P. ovale rbp2 qPCR assay detects P. ovale curtisi and P. ovale wallikeri simultaneously and can be utilized to characterize the prevalence, distribution, and burden of P. ovale in malaria endemic regions. Using multilocus genotyping, we also provided the first description of the prevalence of P. ovale curtisi and P. ovale wallikeri in Western Kenya, a region holoendemic for malaria transmission. Humans can be infected with five malaria parasite species: Plasmodium falciparum, P. vivax, P. malariae, P. knowlesi, and P. ovale. Although the vast majority of malaria morbidity and mortality worldwide can be attributed to P. falciparum, non-falciparum malaria parasites can also cause clinical disease. Researchers use nucleic acid based detection methods, such a polymerase chain reaction (PCR), to detect low-density malaria parasitemias that can evade microscopic detection. P. ovale was recently identified to exist as two subspecies, P. ovale curtisi and P. ovale wallikeri, that look identical but differ genetically. In this study, we developed a novel real-time PCR (qPCR) assay to detect all P. ovale parasites, based on a conserved gene between P. ovale curtisi and P. ovale wallikeri. We also used DNA sequencing to differentiate between P. ovale curtisi and P. ovale wallikeri from a small sample of P. ovale asymptomatic infections in Western Kenya. Through the use of our novel rbp2 qPCR assay, we aim to characterize the prevalence of P. ovale in future epidemiological studies in order to better understand this neglected malaria parasite species.
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Weathers PJ, Towler M, Hassanali A, Lutgen P, Engeu PO. Dried-leaf Artemisia annua: A practical malaria therapeutic for developing countries? World J Pharmacol 2014; 3:39-55. [PMID: 25678989 PMCID: PMC4323188 DOI: 10.5497/wjp.v3.i4.39] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 09/09/2014] [Accepted: 10/10/2014] [Indexed: 02/06/2023] Open
Abstract
Artemisinin from the plant Artemisia annua (A. annua) L., and used as artemisinin combination therapy (ACT), is the current best therapeutic for treating malaria, a disease that hits children and adults especially in developing countries. Traditionally, A. annua was used by the Chinese as a tea to treat “fever”. More recently, investigators have shown that tea infusions and oral consumption of the dried leaves of the plant have prophylactic and therapeutic efficacy. The presence of a complex matrix of chemicals within the leaves seems to enhance both the bioavailability and efficacy of artemisinin. Although about 1000-fold less potent than artemisinin in their antiplasmodial activity, these plant chemicals are mainly small molecules that include other artemisinic compounds, terpenes (mainly mono and sesqui), flavonoids, and polyphenolic acids. In addition, polysaccharide constituents of A. annua may enhance bioavailability of artemisinin. Rodent pharmacokinetics showed longer T½ and Tmax and greater Cmax and AUC in Plasmodium chabaudi-infected mice treated with A. annua dried leaves than in healthy mice. Pharmacokinetics of deoxyartemisinin, a liver metabolite of artemisinin, was more inhibited in infected than in healthy mice. In healthy mice, artemisinin serum levels were > 40-fold greater in dried leaf fed mice than those fed with pure artemisinin. Human trial data showed that when delivered as dried leaves, 40-fold less artemisinin was required to obtain a therapeutic response compared to pure artemisinin. ACTs are still unaffordable for many malaria patients, and cost estimates for A. annua dried leaf tablet production are orders of magnitude less than for ACT, despite improvements in the production capacity. Considering that for > 2000 years this plant was used in traditional Chinese medicine for treatment of fever with no apparent appearance of artemisinin drug resistance, the evidence argues for inclusion of affordable A. annua dried leaf tablets into the arsenal of drugs to combat malaria and other artemisinin-susceptible diseases.
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Towards malaria microscopy at the point-of-contact: an assessment of the diagnostic performance of the Newton Nm1 microscope in Uganda. Parasitology 2014; 141:1819-25. [PMID: 25088228 DOI: 10.1017/s0031182014000833] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Malaria microscopy in sub-Saharan Africa is often restricted by access to light microscopes. To address this gap, a novel portable inverted monocular microscope, the Newton Nm1, was designed and is now commercially available. Its diagnostic performance was assessed in a blinded-slide trial at ×1000 (oil) of Giemsa-stained thick blood films against a conventional microscope as undertaken by four Ugandan Ministry of Health technicians. With the Newton Nm1, diagnostic performance was: sensitivity 93.5% (95% confidence interval (CI) 78.6-99.2%), specificity 100.0% (95% CI 82.4-100.0%), positive predictive value 100.0% (95% CI 88.1-100.0%) and negative predictive value 90.5% (95% CI 69.6-98.8%). Discordance was due to a systematic error underestimating parasitaemia by ~45%; when counting Plasmodium parasites against 200 white blood cells, blood films with low parasitaemia (i.e. <100 μL(-1) of blood) could be overlooked and misclassified. By contrast, specificity was excellent with no false positives encountered. Whilst proven useful, especially in resource-poor environments, it is still unclear how we can ensure the uptake of the Newton Nm1 within sub-Saharan Africa.
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