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Joste V, Coppée R, Bailly J, Rakotoarivony Y, Toko Tchokoteu FG, Achache S, Pradines B, Cottrell G, Ariey F, Khim N, Popovici J, Mita T, Groger M, Ramharter M, Egbo T, Juma DW, Akala H, Houzé S, Clain J. Plasmodium ovale spp dhfr mutations associated with reduced susceptibility to pyrimethamine in sub-Saharan Africa: a retrospective genetic epidemiology and functional study. THE LANCET. MICROBE 2024; 5:669-678. [PMID: 38761813 DOI: 10.1016/s2666-5247(24)00054-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 02/14/2024] [Accepted: 02/21/2024] [Indexed: 05/20/2024]
Abstract
BACKGROUND Mutations in the Plasmodium falciparum dhfr gene confer resistance to pyrimethamine, which is widely used for malaria chemoprevention in Africa. We aimed to evaluate the frequency and evolution of dhfr mutations in Plasmodium ovale spp in Africa and their functional consequences, which are incompletely characterised. METHODS We analysed dhfr mutations and their frequencies in P ovale spp isolates collected between Feb 1, 2004, and Aug 31, 2023, from the French National Malaria Reference Centre collection and from field studies in Benin, Gabon, and Kenya. Genetic patterns of positive selection were investigated. Full-length recombinant wild-type and mutant DHFR enzymes from both P ovale curtisi and P ovale wallikeri were expressed in bacteria to test whether the most common mutations reduced pyrimethamine susceptibility. FINDINGS We included 518 P ovale spp samples (314 P ovale curtisi and 204 P ovale wallikeri). In P ovale curtisi, Ala15Ser-Ser58Arg was the most common dhfr mutation (39%; 124 of 314 samples). In P ovale wallikeri, dhfr mutations were less frequent, with Phe57Leu-Ser58Arg reaching 17% (34 of 204 samples). These two mutants were the most prevalent in central and east Africa and were fixed in Kenyan isolates. We detected six and four other non-synonymous mutations, representing 8% (24 isolates) and 2% (five isolates) of the P ovale curtisi and P ovale wallikeri isolates, respectively. Whole-genome sequencing and microsatellite analyses revealed reduced genetic diversity around the mutant pocdhfr and powdhfr genes. The mutant DHFR proteins showed structural changes at the pyrimethamine binding site in-silico, confirmed by a 4-times increase in pyrimethamine half-maximal inhibitory concentration in an Escherichia coli growth assay for the Phe57Leu-Ser58Arg mutant and 50-times increase for the Ala15Ser-Ser58Arg mutant, compared with the wild-type counterparts. INTERPRETATION The widespread use of sulfadoxine-pyrimethamine for malaria chemoprevention might have exerted fortuitous selection pressure for dhfr mutations in P ovale spp. This calls for closer monitoring of dhfr and dhps mutations in P ovale spp. FUNDING French Ministry of Health, Agence Nationale de la Recherche, and Global Emerging Infections Surveillance branch of the Armed Forces Health Surveillance Division.
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Affiliation(s)
- Valentin Joste
- Université Paris Cité, IRD, MERIT, Paris, France; Centre National de Référence du Paludisme, AP-HP, Hôpital Bichat - Claude-Bernard, Paris, France.
| | - Romain Coppée
- Université de Rouen Normandie, Laboratoire de Parasitologie-Mycologie, UR 7510 ESCAPE, Centre Hospitalier Universitaire de Rouen, Rouen, France
| | | | - Yann Rakotoarivony
- Centre National de Référence du Paludisme, AP-HP, Hôpital Bichat - Claude-Bernard, Paris, France
| | | | | | - Bruno Pradines
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France; Université Aix-Marseille, IRD, SSA, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence du Paludisme, Marseille, France
| | | | - Frédéric Ariey
- INSERM U1016, Institut Cochin, Laboratoire de Parasitologie-Mycologie, Hôpital Cochin, AP-HP, Université Paris Cité, Paris, France
| | - Nimol Khim
- Malaria Research Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Jean Popovici
- Malaria Research Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Toshihiro Mita
- Department of Tropical Medicine and Parasitology, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Mirjam Groger
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Ramharter
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany; Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Timothy Egbo
- Walter Reed Army Institute of Research - Africa (WRAIR-A), Kisumu, Kenya
| | - Dennis W Juma
- Department of Emerging and Infectious Diseases (DEID), Walter Reed Army Institute of Research - Africa (WRAIR-A), Kisumu, Kenya
| | - Hoseah Akala
- Department of Emerging and Infectious Diseases (DEID), Walter Reed Army Institute of Research - Africa (WRAIR-A), Kisumu, Kenya
| | - Sandrine Houzé
- Université Paris Cité, IRD, MERIT, Paris, France; Centre National de Référence du Paludisme, AP-HP, Hôpital Bichat - Claude-Bernard, Paris, France
| | - Jérôme Clain
- Université Paris Cité, IRD, MERIT, Paris, France; Centre National de Référence du Paludisme, AP-HP, Hôpital Bichat - Claude-Bernard, Paris, France
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Popkin-Hall ZR, Seth MD, Madebe RA, Budodo R, Bakari C, Francis F, Pereus D, Giesbrecht DJ, Mandara CI, Mbwambo D, Aaron S, Lusasi A, Lazaro S, Bailey JA, Juliano JJ, Ishengoma DS. Malaria Species Positivity Rates Among Symptomatic Individuals Across Regions of Differing Transmission Intensities in Mainland Tanzania. J Infect Dis 2024; 229:959-968. [PMID: 37992117 PMCID: PMC11011190 DOI: 10.1093/infdis/jiad522] [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: 09/20/2023] [Revised: 11/09/2023] [Accepted: 11/20/2023] [Indexed: 11/24/2023] Open
Abstract
BACKGROUND Recent data indicate that non-Plasmodium falciparum species may be more prevalent than thought in sub-Saharan Africa. Although Plasmodium malariae, Plasmodium ovale spp., and Plasmodium vivax are less severe than P. falciparum, treatment and control are more challenging, and their geographic distributions are not well characterized. METHODS We randomly selected 3284 of 12 845 samples collected from cross-sectional surveys in 100 health facilities across 10 regions of Mainland Tanzania and performed quantitative real-time PCR to determine presence and parasitemia of each malaria species. RESULTS P. falciparum was most prevalent, but P. malariae and P. ovale were found in all but 1 region, with high levels (>5%) of P. ovale in 7 regions. The highest P. malariae positivity rate was 4.5% in Mara and 8 regions had positivity rates ≥1%. We only detected 3 P. vivax infections, all in Kilimanjaro. While most nonfalciparum malaria-positive samples were coinfected with P. falciparum, 23.6% (n = 13 of 55) of P. malariae and 14.7% (n = 24 of 163) of P. ovale spp. were monoinfections. CONCLUSIONS P. falciparum remains by far the largest threat, but our data indicate that malaria elimination efforts in Tanzania will require increased surveillance and improved understanding of the biology of nonfalciparum species.
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Affiliation(s)
- Zachary R Popkin-Hall
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Misago D Seth
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Rashid A Madebe
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Rule Budodo
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Catherine Bakari
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Filbert Francis
- National Institute for Medical Research, Tanga Center, Tanga, Tanzania
| | - Dativa Pereus
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - David J Giesbrecht
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Celine I Mandara
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | | | | | | | - Samwel Lazaro
- National Malaria Control Programme, Dodoma, Tanzania
| | - Jeffrey A Bailey
- Department of Pathology and Laboratory Medicine, Warren Alpert Medical School, Brown University, Providence, Rhode Island, USA
- Center for Computational Molecular Biology, Brown University, Providence, Rhode Island, USA
| | - Jonathan J Juliano
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Deus S Ishengoma
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
- Faculty of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
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Šlapeta J, Sutherland CJ, Fuehrer HP. Calling them names: variants of Plasmodium ovale. Trends Parasitol 2024; 40:205-206. [PMID: 38160179 DOI: 10.1016/j.pt.2023.12.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Affiliation(s)
- Jan Šlapeta
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, New South Wales, Australia.
| | - Colin J Sutherland
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, UK
| | - Hans-Peter Fuehrer
- Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
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Potlapalli VR, Muller MS, Ngasala B, Ali IM, Na YB, Williams DR, Kharabora O, Chhetri S, Liu MS, Carey-Ewend K, Lin FC, Mathias D, Tarimo BB, Juliano JJ, Parr JB, Lin JT. Real-time PCR detection of mixed Plasmodium ovale curtisi and wallikeri infections in human and mosquito hosts. PLoS Negl Trop Dis 2023; 17:e0011274. [PMID: 38064489 PMCID: PMC10732364 DOI: 10.1371/journal.pntd.0011274] [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: 04/04/2023] [Revised: 12/20/2023] [Accepted: 11/21/2023] [Indexed: 12/19/2023] Open
Abstract
Plasmodium ovale curtisi (Poc) and Plasmodium ovale wallikeri (Pow) represent distinct non-recombining Plasmodium species that are increasing in prevalence in sub-Saharan Africa. Though they circulate sympatrically, co-infection within human and mosquito hosts has rarely been described. Separate 18S rRNA real-time PCR assays that detect Poc and Pow were modified to allow species determination in parallel under identical cycling conditions. The lower limit of detection was 0.6 plasmid copies/μL (95% CI 0.4-1.6) for Poc and 4.5 plasmid copies/μL (95% CI 2.7-18) for Pow, or 0.1 and 0.8 parasites/μL, respectively, assuming 6 copies of 18s rRNA per genome. However, the assays showed cross-reactivity at concentrations greater than 103 plasmid copies/μL (roughly 200 parasites/μL). Mock mixtures were used to establish criteria for classifying mixed Poc/Pow infections that prevented false-positive detection while maintaining sensitive detection of the minority ovale species down to 100 copies/μL (<1 parasite/μL). When the modified real-time PCR assays were applied to field-collected blood samples from Tanzania and Cameroon, species identification by real-time PCR was concordant with nested PCR in 19 samples, but additionally detected two mixed Poc/Pow infections where nested PCR detected a single Po species. When real-time PCR was applied to oocyst-positive Anopheles midguts saved from mosquitoes fed on P. ovale-infected persons, mixed Poc/Pow infections were detected in 11/14 (79%). Based on these results, 8/9 P. ovale carriers transmitted both P. ovale species to mosquitoes, though both Po species could only be detected in the blood of two carriers. The described real-time PCR approach can be used to identify the natural occurrence of mixed Poc/Pow infections in human and mosquito hosts and reveals that such co-infections and co-transmission are likely more common than appreciated.
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Affiliation(s)
- Varun R. Potlapalli
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Meredith S. Muller
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Billy Ngasala
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Innocent Mbulli Ali
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Yu Bin Na
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Danielle R. Williams
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Oksana Kharabora
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Srijana Chhetri
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Mei S. Liu
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Kelly Carey-Ewend
- Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Feng-Chang Lin
- Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Derrick Mathias
- Florida Medical Entomology Laboratory, Institute of Food & Agricultural Sciences, University of Florida, Vero Beach, Florida United States of America
| | - Brian B. Tarimo
- Vector Immunity and Transmission Biology Unit, Department of Environmental Health and Ecological Sciences, Ifakara Health Institute-Bagamoyo Office, Bagamoyo, Tanzania
| | - Jonathan J. Juliano
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
- Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Jonathan B. Parr
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Jessica T. Lin
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
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Kojom Foko LP, Singh V. Malaria in pregnancy in India: a 50-year bird's eye. Front Public Health 2023; 11:1150466. [PMID: 37927870 PMCID: PMC10620810 DOI: 10.3389/fpubh.2023.1150466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 09/25/2023] [Indexed: 11/07/2023] Open
Abstract
Introduction In 2021, India contributed for ~79% of malaria cases and ~ 83% of deaths in the South East Asia region. Here, we systematically and critically analyzed data published on malaria in pregnancy (MiP) in India. Methods Epidemiological, clinical, parasitological, preventive and therapeutic aspects of MiP and its consequences on both mother and child were reviewed and critically analyzed. Knowledge gaps and solution ways are also presented and discussed. Several electronic databases including Google scholar, Google, PubMed, Scopus, Wiley Online library, the Malaria in Pregnancy Consortium library, the World Malaria Report, The WHO regional websites, and ClinicalTrials.gov were used to identify articles dealing with MiP in India. The archives of local scientific associations/journals and website of national programs were also consulted. Results Malaria in pregnancy is mainly due to Plasmodium falciparum (Pf) and P. vivax (Pv), and on rare occasions to P. ovale spp. and P. malariae too. The overall prevalence of MiP is ~0.1-57.7% for peripheral malaria and ~ 0-29.3% for placental malaria. Peripheral Pf infection at antenatal care (ANC) visits decreased from ~13% in 1991 to ~7% in 1995-1996 in Madhya Pradesh, while placental Pf infection at delivery unit slightly decreased from ~1.5% in 2006-2007 to ~1% in 2012-2015 in Jharkhand. In contrast, the prevalence of peripheral Pv infection at ANC increased from ~1% in 2006-2007 to ~5% in 2015 in Jharkhand, and from ~0.5% in 1984-1985 to ~1.5% in 2007-2008 in Chhattisgarh. Clinical presentation of MiP is diverse ranging from asymptomatic carriage of parasites to severe malaria, and associated with comorbidities and concurrent infections such as malnutrition, COVID-19, dengue, and cardiovascular disorders. Severe anemia, cerebral malaria, severe thrombocytopenia, and hypoglycemia are commonly seen in severe MiP, and are strongly associated with tragic consequences such as abortion and stillbirth. Congenital malaria is seen at prevalence of ~0-12.9%. Infected babies are generally small-for-gestational age, premature with low birthweight, and suffer mainly from anemia, thrombocytopenia, leucopenia and clinical jaundice. Main challenges and knowledge gaps to MiP control included diagnosis, relapsing malaria, mixed Plasmodium infection treatment, self-medication, low density infections and utility of artemisinin-based combination therapies. Conclusion All taken together, the findings could be immensely helpful to control MiP in malaria endemic areas.
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Joste V, Colard-Itté E, Guillochon É, Ariey F, Coppée R, Clain J, Houzé S. Genetic Profiling of Plasmodium ovale wallikeri Relapses With Microsatellite Markers and Whole-Genome Sequencing. J Infect Dis 2023; 228:1089-1098. [PMID: 37329228 DOI: 10.1093/infdis/jiad216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/14/2023] [Accepted: 06/15/2023] [Indexed: 06/18/2023] Open
Abstract
Like Plasmodium vivax, both Plasmodium ovale curtisi and Plasmodium ovale wallikeri have the ability to cause relapse in humans, defined as recurring asexual parasitemia originating from liver-dormant forms subsequent to a primary infection. Here, we investigated relapse patterns in P ovale wallikeri infections from a cohort of travelers who were exposed to the parasite in sub-Saharan Africa and then experienced relapses after their return to France. Using a novel set of 8 highly polymorphic microsatellite markers, we genotyped 15 P ovale wallikeri relapses. For most relapses, the paired primary and relapse infections were highly genetically related (with 12 being homologous), an observation that was confirmed by whole-genome sequencing for the 4 relapses we further studied. This is, to our knowledge, the first genetic evidence of relapses in P ovale spp.
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Affiliation(s)
- Valentin Joste
- Mère et enfant en milieu tropical, Institut Recherche pour le Développement, Université Paris Cité
- Centre National de Référence du Paludisme, Assistance Publique-Hôpitaux de Paris, Hôpital Bichat-Claude-Bernard
| | - Emma Colard-Itté
- Centre National de Référence du Paludisme, Assistance Publique-Hôpitaux de Paris, Hôpital Bichat-Claude-Bernard
| | - Émilie Guillochon
- Mère et enfant en milieu tropical, Institut Recherche pour le Développement, Université Paris Cité
| | - Frédéric Ariey
- Inserm U1016, Institut Cochin, Laboratoire de parasitologie-mycologie, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, Université de Paris Cité
| | - Romain Coppée
- Université Paris Cité and Sorbonne Paris Nord, Inserm, IAME, Paris, France
| | - Jérôme Clain
- Mère et enfant en milieu tropical, Institut Recherche pour le Développement, Université Paris Cité
- Centre National de Référence du Paludisme, Assistance Publique-Hôpitaux de Paris, Hôpital Bichat-Claude-Bernard
| | - Sandrine Houzé
- Mère et enfant en milieu tropical, Institut Recherche pour le Développement, Université Paris Cité
- Centre National de Référence du Paludisme, Assistance Publique-Hôpitaux de Paris, Hôpital Bichat-Claude-Bernard
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Ansah F, Nyame K, Laryea R, Owusu R, Amon D, Boyetey MJB, Ayeke D, Razak N, Kornu VE, Ashitei S, Owusu-Appiah C, Chirawurah JD, Abugri J, Aniweh Y, Opoku N, Sutherland CJ, Binka FN, Kweku M, Awandare GA, Dinko B. The temporal dynamics of Plasmodium species infection after artemisinin-based combination therapy (ACT) among asymptomatic children in the Hohoe municipality, Ghana. Malar J 2023; 22:271. [PMID: 37710288 PMCID: PMC10500816 DOI: 10.1186/s12936-023-04712-1] [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: 03/14/2023] [Accepted: 09/11/2023] [Indexed: 09/16/2023] Open
Abstract
BACKGROUND The routine surveillance of asymptomatic malaria using nucleic acid-based amplification tests is essential in obtaining reliable data that would inform malaria policy formulation and the implementation of appropriate control measures. METHODS In this study, the prevalence rate and the dynamics of Plasmodium species among asymptomatic children (n = 1697) under 5 years from 30 communities within the Hohoe municipality in Ghana were determined. RESULTS AND DISCUSSION The observed prevalence of Plasmodium parasite infection by polymerase chain reaction (PCR) was 33.6% (571/1697), which was significantly higher compared to that obtained by microscopy [26.6% (451/1697)] (P < 0.0001). Based on species-specific analysis by nested PCR, Plasmodium falciparum infection [33.6% (570/1697)] was dominant, with Plasmodium malariae, Plasmodium ovale and Plasmodium vivax infections accounting for 0.1% (1/1697), 0.0% (0/1697), and 0.0% (0/1697), respectively. The prevalence of P. falciparum infection among the 30 communities ranged from 0.0 to 82.5%. Following artesunate-amodiaquine (AS + AQ, 25 mg/kg) treatment of a sub-population of the participants (n = 184), there was a substantial reduction in Plasmodium parasite prevalence by 100% and 79.2% on day 7 based on microscopy and nested PCR analysis, respectively. However, there was an increase in parasite prevalence from day 14 to day 42, with a subsequent decline on day 70 by both microscopy and nested PCR. For parasite clearance rate analysis, we found a significant proportion of the participants harbouring residual Plasmodium parasites or parasite genomic DNA on day 1 [65.0% (13/20)], day 2 [65.0% (13/20)] and day 3 [60.0% (12/20)] after initiating treatment. Of note, gametocyte carriage among participants was low before and after treatment. CONCLUSION Taken together, the results indicate that a significant number of individuals could harbour residual Plasmodium parasites or parasite genomic DNA after treatment. The study demonstrates the importance of routine surveillance of asymptomatic malaria using sensitive nucleic acid-based amplification techniques.
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Affiliation(s)
- Felix Ansah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Kwamina Nyame
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Rukaya Laryea
- Department of Epidemiology and Biostatistics, Fred Newton Binka School of Public Health, University of Health and Allied Sciences, Hohoe, Ghana
| | - Richard Owusu
- Department of Epidemiology and Biostatistics, Fred Newton Binka School of Public Health, University of Health and Allied Sciences, Hohoe, Ghana
| | - Denick Amon
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Mark-Jefferson Buer Boyetey
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Dzidzor Ayeke
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Nasibatu Razak
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Victor E Kornu
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Sarah Ashitei
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Caleb Owusu-Appiah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Jersley D Chirawurah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - James Abugri
- Department of Biochemistry and Forensic Sciences, School of Chemical and Biochemical Sciences, C. K. Tedam University of Technology and Applied Sciences, Navrongo, Ghana
| | - Yaw Aniweh
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Nicholas Opoku
- Department of Epidemiology and Biostatistics, Fred Newton Binka School of Public Health, University of Health and Allied Sciences, Hohoe, Ghana
| | - Colin J Sutherland
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Fred N Binka
- Department of Epidemiology and Biostatistics, Fred Newton Binka School of Public Health, University of Health and Allied Sciences, Hohoe, Ghana
| | - Margaret Kweku
- Department of Epidemiology and Biostatistics, Fred Newton Binka School of Public Health, University of Health and Allied Sciences, Hohoe, Ghana
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Accra, Ghana
| | - Bismarck Dinko
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
- Department of Biomedical Sciences, School of Basic and Biomedical Sciences, University of Health and Allied Sciences, Ho, Ghana.
- Department of Clinical Microbiology, School of Medicine and Dentistry College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ashanti Region, Ghana.
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Sendor R, Mitchell CL, Chacky F, Mohamed A, Mhamilawa LE, Molteni F, Nyinondi S, Kabula B, Mkali H, Reaves EJ, Serbantez N, Kitojo C, Makene T, Kyaw T, Muller M, Mwanza A, Eckert EL, Parr JB, Lin JT, Juliano JJ, Ngasala B. Similar Prevalence of Plasmodium falciparum and Non-P. falciparum Malaria Infections among Schoolchildren, Tanzania 1. Emerg Infect Dis 2023; 29:1143-1153. [PMID: 37209670 DOI: 10.3201/eid2906.221016] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023] Open
Abstract
Achieving malaria elimination requires considering both Plasmodium falciparum and non-P. falciparum infections. We determined prevalence and geographic distribution of 4 Plasmodium spp. by performing PCR on dried blood spots collected within 8 regions of Tanzania during 2017. Among 3,456 schoolchildren, 22% had P. falciparum, 24% had P. ovale spp., 4% had P. malariae, and 0.3% had P. vivax infections. Most (91%) schoolchildren with P. ovale infections had low parasite densities; 64% of P. ovale infections were single-species infections, and 35% of those were detected in low malaria endemic regions. P. malariae infections were predominantly (73%) co-infections with P. falciparum. P. vivax was detected mostly in northern and eastern regions. Co-infections with >1 non-P. falciparum species occurred in 43% of P. falciparum infections. A high prevalence of P. ovale infections exists among schoolchildren in Tanzania, underscoring the need for detection and treatment strategies that target non-P. falciparum species.
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Potlapalli V, Muller MS, Ngasala B, Ali IM, Na YB, Williams DR, Kharabora O, Chhetri S, Liu MS, Carey-Ewend K, Lin FC, Mathias D, Tarimo BB, Juliano JJ, Parr J, Lin JT. Real-time PCR detection of mixed Plasmodium ovale curtisi and wallikeri species infections in human and mosquito hosts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.31.535020. [PMID: 37034766 PMCID: PMC10081274 DOI: 10.1101/2023.03.31.535020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Plasmodium ovale curtisi (Poc) and Plasmodium ovale wallikeri (Pow) represent distinct non-recombining malaria species that are increasing in prevalence in sub-Saharan Africa. Though they circulate sympatrically, co-infection within human and mosquito hosts has rarely been described. Separate 18S rRNA real-time PCR assays that detect Poc and Pow were modified to allow species determination in parallel under identical cycling conditions. The lower limit of detection was 0.6 plasmid copies/μL (95% CI 0.4-1.6) for Poc and 4.5 plasmid copies/μL (95% CI( 2.7- 18) for Pow, or 0.1 and 0.8 parasites/μL, respectively, assuming 6 copies of 18s rRNA per genome. However, the assays showed cross-reactivity at concentrations greater than 103 plasmid copies/μL (roughly 200 parasites/μL). Mock mixtures were used to establish criteria for classifying mixed Poc/Pow infections that prevented false-positive detection while maintaining sensitive detection of the minority ovale species down to 10° copies/μL (<1 parasite/μL). When the modified real-time PCR assays were applied to field-collected blood samples from Tanzania and Cameroon, species identification by real-time PCR was concordant with nested PCR, but additionally detected two mixed Poc/Pow infections where nested PCR detected a single Po species. When real-time PCR was applied to 14 oocyst-positive Anopheles midguts saved from mosquitoes fed on P. ovate-infected persons, mixed Poc/Pow infections were detected in 11 (79%). Based on these results, 8/9 P. ovate carriers transmitted both P. ovate species to mosquitoes, though both Po species could only be detected in the blood of two carriers. The described real-time PCR approach can be used to identify the natural occurrence of mixed Poc/Pow infections in human and mosquito hosts and reveals that such co-infections and co-transmission are likely more common than appreciated.
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Affiliation(s)
- Varun Potlapalli
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Meredith S Muller
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Billy Ngasala
- Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Innocent Mbulli Ali
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Yu Bin Na
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Danielle R Williams
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC USA
| | - Oksana Kharabora
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Srijana Chhetri
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Mei S Liu
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Kelly Carey-Ewend
- Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC USA
| | - Feng-Chang Lin
- Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC USA
| | - Derrick Mathias
- Florida Medical Entomology Laboratory, Institute of Food & Agricultural Sciences, University of Florida, Vero Beach, FL USA
| | - Brian B Tarimo
- Vector Immunity and Transmission Biology Unit, Department of Environmental Health and Ecological Sciences, Ifakara Health Institute-Bagamoyo Office, Bagamoyo, Tanzania
| | - Jonathan J Juliano
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
- Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC USA
| | - Jonathan Parr
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
| | - Jessica T Lin
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC USA
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Development and Optimization of a Selective Whole-Genome Amplification To Study Plasmodium ovale Spp. Microbiol Spectr 2022; 10:e0072622. [PMID: 36098524 PMCID: PMC9602584 DOI: 10.1128/spectrum.00726-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Since 2010, the human-infecting malaria parasite Plasmodium ovale spp. has been divided into two genetically distinct species, P. ovale wallikeri and P. ovale curtisi. In recent years, application of whole-genome sequencing (WGS) to P. ovale spp. allowed to get a better understanding of its evolutionary history and discover some specific genetic patterns. Nevertheless, WGS data from P. ovale spp. are still scarce due to several drawbacks, including a high level of human DNA contamination in blood samples, infections with commonly low parasite density, and the lack of robust in vitro culture. Here, we developed two selective whole-genome amplification (sWGA) protocols that were tested on six P. ovale wallikeri and five P. ovale curtisi mono-infection clinical samples. Blood leukodepletion by a cellulose-based filtration was used as the gold standard for intraspecies comparative genomics with sWGA. We also demonstrated the importance of genomic DNA preincubation with the endonuclease McrBC to optimize P. ovale spp. sWGA. We obtained high-quality WGS data with more than 80% of the genome covered by ≥5 reads for each sample and identified more than 5,000 unique single-nucleotide polymorphisms (SNPs) per species. We also identified some amino acid changes in pocdhfr and powdhfr for which similar mutations in P. falciparum and P. vivax are associated with pyrimethamine or cycloguanil resistance. In conclusion, we developed two sWGA protocols for P. ovale spp. WGS that will help to design much-needed large-scale P. ovale spp. population studies. IMPORTANCE Plasmodium ovale spp. has the ability to cause relapse, defined as recurring asexual parasitemia originating from liver-dormant forms. Whole-genome sequencing (WGS) data are of importance to identify putative molecular markers associated with relapse or other virulence mechanisms. Due to low parasitemia encountered in P. ovale spp. infections and no in vitro culture available, WGS of P. ovale spp. is challenging. Blood leukodepletion by filtration has been used, but no technique exists yet to increase the quantity of parasite DNA over human DNA when starting from genomic DNA extracted from whole blood. Here, we demonstrated that selective whole-genome amplification (sWGA) is an easy-to-use protocol to obtain high-quality WGS data for both P. ovale spp. species from unprocessed blood samples. The new method will facilitate P. ovale spp. population genomic studies.
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Putaporntip C, Kuamsab N, Rojrung R, Seethamchai S, Jongwutiwes S. Structural organization and sequence diversity of the complete nucleotide sequence encoding the Plasmodium malariae merozoite surface protein-1. Sci Rep 2022; 12:15591. [PMID: 36114242 PMCID: PMC9481586 DOI: 10.1038/s41598-022-19049-z] [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: 03/15/2022] [Accepted: 08/23/2022] [Indexed: 11/28/2022] Open
Abstract
The merozoite surface protein-1 (MSP1) is a prime candidate for an asexual blood stage vaccine against malaria. However, polymorphism in this antigen could compromise the vaccine’s efficacy. Although the extent of sequence variation in MSP1 has been analyzed from various Plasmodium species, little is known about structural organization and diversity of this locus in Plasmodium malariae (PmMSP1). Herein, we have shown that PmMSP1 contained five conserved and four variable blocks based on analysis of the complete coding sequences. Variable blocks were characterized by short insertion and deletion variants (block II), polymorphic nonrepeat sequences (block IV), complex repeat structure with size variation (block VI) and degenerate octapeptide repeats (block VIII). Like other malarial MSP1s, evidences of intragenic recombination have been found in PmMSP1. The rate of nonsynonymous nucleotide substitutions significantly exceeded that of synonymous nucleotide substitutions in block IV, suggesting positive selection in this region. Codon-based analysis of deviation from neutrality has identified a codon under purifying selection located in close proximity to the homologous region of the 38 kDa/42 kDa cleavage site of P. falciparum MSP1. A number of predicted linear B-cell epitopes were identified across both conserved and variable blocks of the protein. However, polymorphism in repeat-containing blocks resulted in alteration of the predicted linear B-cell epitope scores across variants. Although a number of predicted HLA-class II-binding peptides were identified in PmMSP1, all variants of block IV seemed not to be recognized by common HLA-class II alleles among Thai population, suggesting that diversity in this positive selection region could probably affect host immune recognition. The data on structural diversity in PmMSP1 could be useful for further studies such as vaccine development and strain characterization of this neglected malaria parasite.
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12
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Genetic Diversity and Phylogenetic Relatedness of Plasmodium ovale curtisi and Plasmodium ovale wallikeri in sub-Saharan Africa. Microorganisms 2022; 10:microorganisms10061147. [PMID: 35744665 PMCID: PMC9227610 DOI: 10.3390/microorganisms10061147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/29/2022] [Accepted: 05/30/2022] [Indexed: 12/14/2022] Open
Abstract
P. ovale was until recently thought to be a single unique species. However, the deployment of more sensitive tools has led to increased diagnostic sensitivity, including new evidence supporting the presence of two sympatric species: P. ovale curtisi (Poc) and P. ovale wallikeri (Pow). The increased reports and evolution of P. ovale subspecies are concerning for sub-Saharan Africa where the greatest burden of malaria is borne. Employing published sequence data, we set out to decipher the genetic diversity and phylogenetic relatedness of P. ovale curtisi and P. ovale wallikeri using the tryptophan-rich protein and small subunit ribosomal RNA genes from Gabon, Senegal, Ethiopia and Kenya. Higher number of segregating sites were recorded in Poc isolates from Gabon than from Ethiopia, with a similar trend in the number of haplotypes. With regards to Pow, the number of segregating sites and haplotypes from Ethiopia were higher than from those in Gabon. Poc from Kenya, had higher segregating sites (20), and haplotypes (4) than isolates from Senegal (8 and 3 respectively), while nucleotide from Senegal were more diverse (θw = 0.02159; π = 0.02159) than those from Kenya (θw = 0.01452; π = 0.01583). Phylogenetic tree construction reveal two large clades with Poc from Gabon and Ethiopia, and distinct Gabonese and Ethiopian clades on opposite ends. A similar observation was recorded for the phylogeny of Poc isolates from Kenya and Senegal. With such results, there is a high potential that ovale malaria control measures deployed in one country may be effective in the other since parasite from both countries show some degree of relatedness. How this translates to malaria control efforts throughout the continent would be next step deserving more studies.
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13
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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: 10] [Impact Index Per Article: 5.0] [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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14
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Groger M, Tona Lutete G, Mombo-Ngoma G, Ntamabyaliro NY, Kahunu Mesia G, Muena Mujobu TB, Dimessa Mbadinga LB, Zoleko Manego R, Egger-Adam D, Borghini-Fuhrer I, Shin J, Miller R, Arbe-Barnes S, Duparc S, Ramharter M. Effectiveness of pyronaridine-artesunate against Plasmodium malariae, Plasmodium ovale spp, and mixed-Plasmodium infections: a post-hoc analysis of the CANTAM-Pyramax trial. THE LANCET MICROBE 2022; 3:e598-e605. [PMID: 35654079 PMCID: PMC9329129 DOI: 10.1016/s2666-5247(22)00092-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/20/2022] [Accepted: 04/08/2022] [Indexed: 12/21/2022] Open
Abstract
Background Methods Findings Interpretation Funding
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Tarimo BB, Nyasembe VO, Ngasala B, Basham C, Rutagi IJ, Muller M, Chhetri SB, Rubinstein R, Juliano JJ, Loya M, Dinglasan RR, Lin JT, Mathias DK. Seasonality and transmissibility of Plasmodium ovale in Bagamoyo District, Tanzania. Parasit Vectors 2022; 15:56. [PMID: 35164867 PMCID: PMC8842944 DOI: 10.1186/s13071-022-05181-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/12/2021] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Plasmodium ovale is a neglected malarial parasite that can form latent hypnozoites in the human liver. Over the last decade, molecular surveillance studies of non-falciparum malaria in Africa have highlighted that P. ovale is circulating below the radar, including areas where Plasmodium falciparum is in decline. To eliminate malaria where P. ovale is endemic, a better understanding of its epidemiology, asymptomatic carriage, and transmission biology is needed. METHODS We performed a pilot study on P. ovale transmission as part of an ongoing study of human-to-mosquito transmission of P. falciparum from asymptomatic carriers. To characterize the malaria asymptomatic reservoir, cross-sectional qPCR surveys were conducted in Bagamoyo, Tanzania, over three transmission seasons. Positive individuals were enrolled in transmission studies of P. falciparum using direct skin feeding assays (DFAs) with Anopheles gambiae s.s. (IFAKARA strain) mosquitoes. For a subset of participants who screened positive for P. ovale on the day of DFA, we incubated blood-fed mosquitoes for 14 days to assess sporozoite development. RESULTS Molecular surveillance of asymptomatic individuals revealed a P. ovale prevalence of 11% (300/2718), compared to 29% (780/2718) for P. falciparum. Prevalence for P. ovale was highest at the beginning of the long rainy season (15.5%, 128/826) in contrast to P. falciparum, which peaked later in both the long and short rainy seasons. Considering that these early-season P. ovale infections were low-density mono-infections (127/128), we speculate many were due to hypnozoite-induced relapse. Six of eight P. ovale-infected asymptomatic individuals who underwent DFAs successfully transmitted P. ovale parasites to A. gambiae. CONCLUSIONS Plasmodium ovale is circulating at 4-15% prevalence among asymptomatic individuals in coastal Tanzania, largely invisible to field diagnostics. A different seasonal peak from co-endemic P. falciparum, the capacity to relapse, and efficient transmission to Anopheles vectors likely contribute to its persistence amid control efforts focused on P. falciparum.
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Affiliation(s)
- Brian B. Tarimo
- Vector Immunity and Transmission Biology Unit, Department of Environmental Health and Ecological Science, Ifakara Health Institute-Bagamoyo Office, P.O. Box 74, Bagamoyo, Coast Region 61301 Tanzania
| | - Vincent O. Nyasembe
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611 USA
| | - Billy Ngasala
- Department of Parasitology and Medical Entomology, School of Public Health and Social Sciences, Muhimbili University of Health and Allied Sciences, Dar es Salaam, 11103 Tanzania
| | - Christopher Basham
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599 USA
| | - Isaack J. Rutagi
- Vector Immunity and Transmission Biology Unit, Department of Environmental Health and Ecological Science, Ifakara Health Institute-Bagamoyo Office, P.O. Box 74, Bagamoyo, Coast Region 61301 Tanzania
| | - Meredith Muller
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599 USA
| | - Srijana B. Chhetri
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599 USA
| | - Rebecca Rubinstein
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599 USA
| | - Jonathan J. Juliano
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599 USA
| | - Mwajabu Loya
- Department of Parasitology and Medical Entomology, School of Public Health and Social Sciences, Muhimbili University of Health and Allied Sciences, Dar es Salaam, 11103 Tanzania
| | - Rhoel R. Dinglasan
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611 USA
| | - Jessica T. Lin
- Institute of Global Health and Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599 USA
| | - Derrick K. Mathias
- Department of Entomology and Nematology, Florida Medical Entomology Laboratory, Institute of Food and Agricultural Sciences, University of Florida, Vero Beach, FL 32962 USA
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Putaporntip C, Kuamsab N, Seethamchai S, Pattanawong U, Rojrung R, Yanmanee S, Cheng CW, Jongwutiwes S. Cryptic Plasmodium inui and P. fieldi infections among symptomatic malaria patients in Thailand. Clin Infect Dis 2021; 75:805-812. [PMID: 34971372 DOI: 10.1093/cid/ciab1060] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Some nonhuman primate Plasmodium species including P. knowlesi and P. cynomolgi can cross-transmit from macaque natural hosts to humans under natural infection. This study aims to retrospectively explore other simian Plasmodium species in the blood samples of symptomatic malaria patients in Thailand. METHODS A total of 5271 blood samples from acute febrile patients from 5 malaria endemic provinces and 1015 blood samples from long-tailed and pig-tailed macaques from 3 locations were examined for Plasmodium species by microscopy and species-specific polymerase chain reaction. The Plasmodium mitochondrial cytochrome oxidase 1 (COX1) gene was analyzed by amplicon deep sequencing as well as Sanger sequencing from recombinant plasmid clones to reaffirm and characterize P. inui and P. fieldi. RESULTS Besides human malaria, P. knowlesi, P. cynomolgi, P. inui and P. fieldi infections were diagnosed in 15, 21, 19 and 3 patients, respectively. Most P. inui and all P. fieldi infected patients had simultaneous infections with other Plasmodium species, and seemed to be responsive to chloroquine or artemisinin-mefloquine. P. inui was the most prevalent species among macaque populations. Phylogenetic analysis of the COX1 sequences from human and macaque isolates reveals the genetic diversity of P. inui and suggests that multiple parasite strains have been incriminated in human infections. CONCLUSIONS Both P. inui and P. fieldi could establish infection in humans under natural transmission. Despite occurring at a low prevalence and mostly co-existing with other Plasmodium species, P. inui infections in humans have a wide distribution in Thailand.
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Affiliation(s)
- Chaturong Putaporntip
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Napaporn Kuamsab
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Sunee Seethamchai
- Department of Biology, Faculty of Science, Naresuan University, Pitsanulok, Thailand
| | - Urassaya Pattanawong
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Rattanaporn Rojrung
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Surasuk Yanmanee
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Chew Weng Cheng
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, UK
| | - Somchai Jongwutiwes
- Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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Aggarwal S, Peng WK, Srivastava S. Multi-Omics Advancements towards Plasmodium vivax Malaria Diagnosis. Diagnostics (Basel) 2021; 11:2222. [PMID: 34943459 PMCID: PMC8700291 DOI: 10.3390/diagnostics11122222] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/21/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Plasmodium vivax malaria is one of the most lethal infectious diseases, with 7 million infections annually. One of the roadblocks to global malaria elimination is the lack of highly sensitive, specific, and accurate diagnostic tools. The absence of diagnostic tools in particular has led to poor differentiation among parasite species, poor prognosis, and delayed treatment. The improvement necessary in diagnostic tools can be broadly grouped into two categories: technologies-driven and omics-driven progress over time. This article discusses the recent advancement in omics-based malaria for identifying the next generation biomarkers for a highly sensitive and specific assay with a rapid and antecedent prognosis of the disease. We summarize the state-of-the-art diagnostic technologies, the key challenges, opportunities, and emerging prospects of multi-omics-based sensors.
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Affiliation(s)
- Shalini Aggarwal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India;
| | - Weng Kung Peng
- Songshan Lake Materials Laboratory, Building A1, University Innovation Park, Dongguan 523808, China
- Precision Medicine-Engineering Group, International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal
| | - Sanjeeva Srivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India;
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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: 16] [Impact Index Per Article: 5.3] [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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19
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Markus MB. Safety and Efficacy of Tafenoquine for Plasmodium vivax Malaria Prophylaxis and Radical Cure: Overview and Perspectives. Ther Clin Risk Manag 2021; 17:989-999. [PMID: 34526770 PMCID: PMC8435617 DOI: 10.2147/tcrm.s269336] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 08/20/2021] [Indexed: 11/23/2022] Open
Abstract
This article is inter alia a brief, first-stop guide to possible adverse events (AEs) associated with tafenoquine (TQ) intake. Safety and efficacy findings for TQ in Plasmodium vivax malaria prophylaxis and radical cure are summarized and some of the latest TQ-related studies (published in 2020 and 2021) are highlighted. In addition, little-known biological and other matters concerning malaria parasites and 8-aminoquinoline (8-AQ) drug action are discussed and some correct terminology pertinent to malaria is explained.
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Affiliation(s)
- Miles B Markus
- School of Animal, Plant and Environmental Sciences, Faculty of Science, University of the Witwatersrand, Johannesburg, South Africa
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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20
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Wångdahl A, Sondén K, Wyss K, Stenström C, Björklund D, Zhang J, Hervius Askling H, Carlander C, Hellgren U, Färnert A. Relapse of Plasmodium vivax and Plasmodium ovale malaria with and without primaquine treatment in a non-endemic area. Clin Infect Dis 2021; 74:1199-1207. [PMID: 34216464 PMCID: PMC8994585 DOI: 10.1093/cid/ciab610] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Indexed: 01/14/2023] Open
Abstract
Background The effect of primaquine in preventing Plasmodium vivax relapses from dormant stages is well established. For Plasmodium ovale, the relapse characteristics and the use of primaquine is not as well studied. We set to evaluate the relapsing properties of these 2 species, in relation to primaquine use among imported malaria cases in a nonendemic setting. Methods We performed a nationwide retrospective study of malaria diagnosed in Sweden 1995–2019, by reviewing medical records of 3254 cases. All episodes of P. vivax (n = 972) and P. ovale (n = 251) were selected for analysis. Results First time relapses were reported in 80/857 (9.3%) P. vivax and 9/220 (4.1%) P. ovale episodes, respectively (P < .01). Without primaquine, the risk for relapse was higher in P. vivax, 20/60 (33.3%), compared to 3/30 (10.0%) in P. ovale (hazard ratio [HR] 3.5, 95% confidence interval [CI] 1.0–12.0). In P. vivax, patients prescribed primaquine had a reduced risk of relapse compared to episodes without relapse preventing treatment, 7.1% vs 33.3% (HR 0.2, 95% CI .1–.3). In P. ovale, the effect of primaquine on the risk of relapse did not reach statistical significance, with relapses seen in 2.8% of the episodes compared to 10.0% in patients not receiving relapse preventing treatment (HR 0.3, 95% CI .1–1.1). Conclusions The risk of relapse was considerably lower in P. ovale than in P. vivax infections indicating different relapsing features between the two species. Primaquine was effective in preventing P. vivax relapse. In P. ovale, relapse episodes were few, and the supportive evidence for primaquine remains limited.
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Affiliation(s)
- Andreas Wångdahl
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Västerås Hospital, Västerås, Sweden
| | - Klara Sondén
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Katja Wyss
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Christine Stenström
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - David Björklund
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Jessica Zhang
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Helena Hervius Askling
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Christina Carlander
- Department of Infectious Diseases, Västerås Hospital, Västerås, Sweden.,Division of Infectious Diseases, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Urban Hellgren
- Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden.,Division of Infectious Diseases, Department of Medicine Huddinge, 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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21
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The Pan African Vivax and Ovale Network (PAVON): Refocusing on Plasmodium vivax, ovale and asymptomatic malaria in sub-Saharan Africa. Parasitol Int 2021; 84:102415. [PMID: 34216801 DOI: 10.1016/j.parint.2021.102415] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 11/20/2022]
Abstract
The recent World Malaria report shows that progress in malaria elimination has stalled. Current data acquisition by NMCPs depend on passive case detection and clinical reports focused mainly on Plasmodium falciparum (Pf). In recent times, several countries in sub-Saharan Africa have reported cases of Plasmodium vivax (Pv) with a considerable number being Duffy negative. The burden of Pv and Plasmodium ovale (Po) appear to be more than acknowledged. Similarly, the contribution of asymptomatic malaria in transmission is hardly considered by NMCPs in Africa. Inclusion of these as targets in malaria elimination agenda is necessary to achieve elimination goal, as these harbor hypnozoites. The Pan African Vivax and Ovale Network (PAVON) is a new consortium of African Scientists working in Africa on the transmission profile of Pv and Po. The group collaborates with African NMCPs to train in Plasmodium molecular diagnostics, microscopy, and interpretation of molecular data from active surveys to translate into policy. Details of the mission, rational and modus operandi of the group are outlined.
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22
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Joste V, Bailly J, Hubert V, Pauc C, Gendrot M, Guillochon E, Madamet M, Thellier M, Kendjo E, Argy N, Pradines B, Houzé S. Plasmodium ovale wallikeri and P. ovale curtisi Infections and Diagnostic Approaches to Imported Malaria, France, 2013-2018. Emerg Infect Dis 2021; 27. [PMID: 33496652 PMCID: PMC7853592 DOI: 10.3201/eid2702.202143] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Patients infected with P. ovale wallikeri displayed deeper thrombocytopenia and a shorter latency period. We retrospectively analyzed epidemiologic, clinical, and biologic characteristics of 368 Plasmodium ovale wallikeri and 309 P. ovale curtisi infections treated in France during January 2013–December 2018. P. ovale wallikeri infections displayed deeper thrombocytopenia and shorter latency periods. Despite similar clinical manifestations, P. ovale wallikeri–infected patients were more frequently treated with artemisinin-based combination therapy. Although the difference was not statistically significant, P. ovale wallikeri–infected patients were 5 times more frequently hospitalized in intensive care or intermediate care and had a higher proportion of severe thrombocytopenia than P. ovale curtisi–infected patients. Rapid diagnostic tests that detect aldolase were more efficient than those detecting Plasmodium lactate dehydrogenase. Sequence analysis of the potra gene from 90 P. ovale isolates reveals an insufficient polymorphism for relapse typing.
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23
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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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24
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Mahittikorn A, Masangkay FR, Kotepui KU, Milanez GDJ, Kotepui M. Comparison of Plasmodium ovale curtisi and Plasmodium ovale wallikeri infections by a meta-analysis approach. Sci Rep 2021; 11:6409. [PMID: 33742015 PMCID: PMC7979700 DOI: 10.1038/s41598-021-85398-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 03/02/2021] [Indexed: 12/12/2022] Open
Abstract
Malaria caused by Plasmodium ovale species is considered a neglected tropical disease with limited information about its characteristics. It also remains unclear whether the two distinct species P. ovale curtisi and P. ovale wallikeri exhibit differences in their prevalence, geographic distribution, clinical characteristics, or laboratory parameters. Therefore, this study was conducted to clarify these differences to support global malaria control and eradication programs. Studies reporting the occurrence of P. ovale curtisi and P. ovale wallikeri were explored in databases. Differences in proportion, clinical data, and laboratory parameters between the two species were estimated using a random-effects model and expressed as pooled odds ratios (ORs), mean difference (MD), or standardized MD depending on the types of extracted data. The difference in geographical distribution was visualized by mapping the origin of the two species. A total of 1453 P. ovale cases extracted from 35 studies were included in the meta-analysis. The p-value in the meta-analyses provided evidence favoring a real difference between P. ovale curtisi malaria cases (809/1453, 55.7%) and P. ovale wallikeri malaria cases (644/1453, 44.3%) (p: 0.01, OR 1.61, 95% CI 0.71-3.63, I2: 77%). Subgroup analyses established evidence favoring a real difference between P. ovale curtisi and P. ovale wallikeri malaria cases among the imported cases (p: 0.02, 1135 cases). The p value in the meta-analyses provided evidence favoring a real difference in the mean latency period between P. ovale curtisi (289 cases) and P. ovale wallikeri malaria (266 cases) (p: 0.03, MD: 27.59, 95% CI 1.99-53.2, I2: 94%), total leukocyte count (p < 0.0001, MD: 840, 95% CI 610-1070, I2: 0%, two studies) and platelet count (p < 0.0001, MD: 44,750, 95% CI 2900-60,500, I2: 32%, three studies). Four continents were found to have reports of P. ovale spp., among which Africa had the highest number of reports for both P. ovale spp. in its 37 countries, with a global proportion of 94.46%, and an almost equal distribution of both P. ovale spp., where P. ovale curtisi and P. ovale wallikeri reflected 53.09% and 46.90% of the continent's proportion, respectively. This is the first systematic review and meta-analysis to demonstrate the differences in the characteristics of the two distinct P. ovale species. Malaria caused by P. ovale curtisi was found in higher proportions among imported cases and had longer latency periods, higher platelet counts, and higher total leukocyte counts than malaria caused by P. ovale wallikeri. Further studies with a larger sample size are required to confirm the differences or similarities between these two species to promote malaria control and effective eradication programs.
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Affiliation(s)
- Aongart Mahittikorn
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Frederick Ramirez Masangkay
- Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University-Manila, Manila, Philippines
| | - Kwuntida Uthaisar Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Giovanni De Jesus Milanez
- Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University-Manila, Manila, Philippines
| | - Manas Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand.
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25
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Zhang T, Wang S, Wang D, Auburn S, Lu S, Xu X, Jiang J, Lyu X, Yu C, Tian C, Li S, Li W. Epidemiological profile of Plasmodium ovale spp. imported from Africa to Anhui Province, China, 2012-2019. Malar J 2021; 20:15. [PMID: 33407463 PMCID: PMC7788861 DOI: 10.1186/s12936-020-03551-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 12/12/2020] [Indexed: 11/17/2022] Open
Abstract
Background Although autochthonous malaria cases are no longer reported in Anhui Province, China, imported malaria has become a major health concern. The proportion of reported malaria cases caused by Plasmodium ovale spp. increased to levels higher than expected during 2012 to 2019, and showed two peaks, 19.69% in 2015 and 19.35% in 2018. Methods A case-based retrospective study was performed using data collected from the China Information System for Disease Control and Prevention (CISDCP) and Information System for Parasitic Disease Control and Prevention (ISPDCP) from 2012 to 2019 to assess the trends and differences between Plasmodium ovale curtisi (P. o. curtisi) and Plasmodium ovale wallikeri (P. o. wallikeri). Epidemiological characteristics were analyzed using descriptive statistics. Results Plasmodium o. curtisi and P. o. wallikeri were found to simultaneously circulate in 14 African countries. Among 128 patients infected with P. ovale spp., the proportion of co-infection cases was 10.16%. Six cases of co-infection with P. ovale spp. and P. falciparum were noted, each presenting with two clinical attacks (the first attack was due to P. falciparum and the second was due to P. ovale spp.) at different intervals. Accurate identification of the infecting species was achieved among only 20.00% of cases of P. ovale spp. infection. At the reporting units, 32.17% and 6.96% of cases of P. ovale spp. infection were misdiagnosed as P. vivax and P. falciparum infections, respectively. Conclusion The present results indicate that the potential of P. ovale spp. to co-infect with other Plasmodium species has been previously underestimated, as is the incidence of P. ovale spp. in countries where malaria is endemic. P. o. curtisi may have a long latency period of > 3 years and potentially cause residual foci, thus posing challenges to the elimination of malaria in P. ovale spp.-endemic areas. Considering the low rate of species identification, more sensitive point-of-care detection methods need to be developed for P. ovale spp. and introduced in non-endemic areas.
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Affiliation(s)
- Tao Zhang
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Shuqi Wang
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Duoquan Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, China
| | - Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Shenning Lu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, China
| | - Xian Xu
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Jingjing Jiang
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Xiaofeng Lyu
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Chen Yu
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Cuicui Tian
- Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601, China
| | - Shizhu Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, China.
| | - Weidong Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, China.
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26
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Heinemann M, Phillips RO, Vinnemeier CD, Rolling CC, Tannich E, Rolling T. High prevalence of asymptomatic malaria infections in adults, Ashanti Region, Ghana, 2018. Malar J 2020; 19:366. [PMID: 33046056 PMCID: PMC7552528 DOI: 10.1186/s12936-020-03441-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 10/06/2020] [Indexed: 01/10/2023] Open
Abstract
Background Ghana is among the high-burden countries for malaria infections and recently reported a notable increase in malaria cases. While asymptomatic parasitaemia is increasingly recognized as a hurdle for malaria elimination, studies on asymptomatic malaria are scarce, and usually focus on children and on non-falciparum species. The present study aims to assess the prevalence of asymptomatic Plasmodium falciparum and non-falciparum infections in Ghanaian adults in the Ashanti region during the high transmission season. Methods Asymptomatic adult residents from five villages in the Ashanti Region, Ghana, were screened for Plasmodium species by rapid diagnostic test (RDT) and polymerase chain reaction (PCR) during the rainy season. Samples tested positive were subtyped using species-specific real-time PCR. For all Plasmodium ovale infections additional sub-species identification was performed. Results Molecular prevalence of asymptomatic Plasmodium infection was 284/391 (73%); only 126 (32%) infections were detected by RDT. While 266 (68%) participants were infected with Plasmodium falciparum, 33 (8%) were infected with Plasmodium malariae and 34 (9%) with P. ovale. The sub-species P. ovale curtisi and P. ovale wallikeri were identified to similar proportions. Non-falciparum infections usually presented as mixed infections with P. falciparum. Conclusions Most adult residents in the Ghanaian forest zone are asymptomatic Plasmodium carriers. The high Plasmodium prevalence not detected by RDT in adults highlights that malaria eradication efforts must target all members of the population. Beneath Plasmodium falciparum, screening and treatment must also include infections with P. malariae, P. o. curtisi and P. o. wallikeri.
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Affiliation(s)
- Melina Heinemann
- Division of Infectious Diseases, I. Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.,Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,Weizmann Institute of Science, Rehovot, Israel
| | - Richard O Phillips
- Kumasi Center for Collaborative Research in Tropical Medicine, Kumasi, Ghana
| | - Christof D Vinnemeier
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Christina C Rolling
- Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.,NYU Langone Medical Center, New York, NY, USA
| | - Egbert Tannich
- National Reference Centre for Tropical Pathogens, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Centre for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany
| | - Thierry Rolling
- Division of Infectious Diseases, I. Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany. .,German Centre for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Hamburg, Germany. .,Department of Clinical Immunology of Infectious Diseases, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. .,Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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27
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Chen M, Dong Y, Deng Y, Xu Y, Liu Y, Zhang C, Huang H. Polymorphism analysis of propeller domain of k13 gene in Plasmodium ovale curtisi and Plasmodium ovale wallikeri isolates original infection from Myanmar and Africa in Yunnan Province, China. Malar J 2020; 19:246. [PMID: 32660505 PMCID: PMC7359257 DOI: 10.1186/s12936-020-03317-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 07/04/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Eighteen imported ovale malaria cases imported from Myanmar and various African countries have been reported in Yunnan Province, China from 2013 to 2018. All of them have been confirmed by morphological examination and 18S small subunit ribosomal RNA gene (18S rRNA) based PCR in YNRL. Nevertheless, the subtypes of Plasmodium ovale could not be identified based on 18S rRNA gene test, thus posing challenges on its accurate diagnosis. To help establish a more sensitive and specific method for the detection of P. ovale genes, this study performs sequence analysis on k13-propeller polymorphisms in P. ovale. METHODS Dried blood spots (DBS) from ovale malaria cases were collected from January 2013 to December 2018, and the infection sources were confirmed according to epidemiological investigation. DNA was extracted, and the coding region (from 206th aa to 725th aa) in k13 gene propeller domain was amplified using nested PCR. Subsequently, the amplified products were sequenced and compared with reference sequence to obtain CDS. The haplotypes and mutation loci of the CDS were analysed, and the spatial structure of the amino acid peptide chain of k13 gene propeller domain was predicted by SWISS-MODEL. RESULTS The coding region from 224th aa to 725th aa of k13 gene from P. ovale in 83.3% of collected samples (15/18) were amplified. Three haplotypes were observed in 15 samples, and the values of Ka/Ks, nucleic acid diversity index (π) and expected heterozygosity (He) were 3.784, 0.0095, and 0.4250. Curtisi haplotype, Wallikeri haplotype, and mutant type accounted for 73.3% (11/15), 20.0% (3/15), and 6.7% (1/15). The predominant haplotypes of P. ovale curtisi were determined in all five Myanmar isolates. Of the ten African isolates, six were identified as P. o. curtisi, three were P. o. wallikeri and one was mutant type. Base substitutions between the sequences of P. o. curtisi and P. o. wallikeri were determined at 38 loci, such as c.711. Moreover, the A > T base substitution at c.1428 was a nonsynonymous mutation, resulting in amino acid variation of T476S in the 476th position. Compared with sequence of P. o. wallikeri, the double nonsynonymous mutations of G > A and A > T at the sites of c.1186 and c.1428 leads to the variations of D396N and T476S for the 396th and 476th amino acids positions. For P. o. curtisi and P. o. wallikeri, the peptide chains in the coding region from 224th aa to 725th aa of k13 gene merely formed a monomeric spatial model, whereas the double-variant peptide chains of D396N and T476S formed homodimeric spatial model. CONCLUSION The propeller domain of k13 gene in the P. ovale isolates imported into Yunnan Province from Myanmar and Africa showed high differentiation. The sequences of Myanmar-imported isolates belong to P. o. curtisi, while the sequences of African isolates showed the sympatric distribution from P. o. curtisi, P. o. wallikeri and mutant isolates. The CDS with a double base substitution formed a dimeric spatial model to encode the peptide chain, which is completely different from the monomeric spatial structure to encode the peptide chain from P. o. curtisi and P. o. wallikeri.
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Affiliation(s)
- Mengni Chen
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China
| | - Ying Dong
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China.
| | - Yan Deng
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China
| | - Yanchun Xu
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China
| | - Yan Liu
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China
| | - Canglin Zhang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China
| | - Herong Huang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Key Laboratory of Vector-Borne Diseases Control and Research, Yunnan Centre of Malaria Research, Academician Workstation of Professor Jin Ningyi, Expert Workstation of Professor Jiang Lubin, Pu'er, 665000, China
- School of Basic Medical Sciences, Dali University, Dali, 667000, China
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28
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Mathema VB, Nakeesathit S, White NJ, Dondorp AM, Imwong M. Genome-wide microsatellite characteristics of five human Plasmodium species, focusing on Plasmodium malariae and P. ovale curtisi. Parasite 2020; 27:34. [PMID: 32410726 PMCID: PMC7227371 DOI: 10.1051/parasite/2020034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 04/30/2020] [Indexed: 12/16/2022] Open
Abstract
Microsatellites can be utilized to explore genotypes, population structure, and other genomic features of eukaryotes. Systematic characterization of microsatellites has not been a focus for several species of Plasmodium, including P. malariae and P. ovale, as the majority of malaria elimination programs are focused on P. falciparum and to a lesser extent P. vivax. Here, five human malaria species (P. falciparum, P. vivax, P. malariae, P. ovale curtisi, and P. knowlesi) were investigated with the aim of conducting in-depth categorization of microsatellites for P. malariae and P. ovale curtisi. Investigation of reference genomes for microsatellites with unit motifs of 1-10 base pairs indicates high diversity among the five Plasmodium species. Plasmodium malariae, with the largest genome size, displays the second highest microsatellite density (1421 No./Mbp; 5% coverage) next to P. falciparum (3634 No./Mbp; 12% coverage). The lowest microsatellite density was observed in P. vivax (773 No./Mbp; 2% coverage). A, AT, and AAT are the most commonly repeated motifs in the Plasmodium species. For P. malariae and P. ovale curtisi, microsatellite-related sequences are observed in approximately 18-29% of coding sequences (CDS). Lysine, asparagine, and glutamic acids are most frequently coded by microsatellite-related CDS. The majority of these CDS could be related to the gene ontology terms "cell parts," "binding," "developmental processes," and "metabolic processes." The present study provides a comprehensive overview of microsatellite distribution and can assist in the planning and development of potentially useful genetic tools for further investigation of P. malariae and P. ovale curtisi epidemiology.
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Affiliation(s)
- Vivek Bhakta Mathema
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University 10400 Bangkok Thailand
| | - Supatchara Nakeesathit
- Mahidol–Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University 10400 Bangkok Thailand
| | - Nicholas J. White
- Mahidol–Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University 10400 Bangkok Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford OX1 2JD Oxford United Kingdom
| | - Arjen M. Dondorp
- Mahidol–Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University 10400 Bangkok Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford OX1 2JD Oxford United Kingdom
| | - Mallika Imwong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University 10400 Bangkok Thailand
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Affiliation(s)
- Mirjam Groger
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine and I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Michael Ramharter
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine and I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,German Center for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany
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Lin JT, Parr JB, Ngasala B. Non-falciparum Malaria in Africa and Learning From Plasmodium vivax in Asia. Clin Infect Dis 2020; 70:2018-2019. [PMID: 31408098 PMCID: PMC7346758 DOI: 10.1093/cid/ciz780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Jessica T Lin
- Institute of Global Health and Infectious Diseases, University of North Carolina, Chapel Hill
| | - Jonathan B Parr
- Institute of Global Health and Infectious Diseases, University of North Carolina, Chapel Hill
| | - Billy Ngasala
- Department of Parasitology and Medical Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
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31
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Frickmann H, Wegner C, Ruben S, Loderstädt U, Tannich E. A comparison of two PCR protocols for the differentiation of Plasmodium ovale species and implications for clinical management in travellers returning to Germany: a 10-year cross-sectional study. Malar J 2019; 18:272. [PMID: 31399031 PMCID: PMC6688346 DOI: 10.1186/s12936-019-2901-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 08/02/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND To assess the occurrence of Plasmodium ovale wallikeri and Plasmodium ovale curtisi species in travellers returning to Germany, two real-time PCR protocols for the detection and differentiation of the two P. ovale species were compared. Results of parasite differentiation were correlated with patient data. METHODS Residual nucleic acid extractions from EDTA blood samples of patients with P. ovale spp. malaria, collected between 2010 and 2019 at the National Reference Centre for Tropical Pathogens in Germany, were subjected to further parasite discrimination in a retrospective assessment. All samples had been analysed by microscopy and by P. ovale spp.-specific real-time PCR without discrimination on species level. Two different real-time PCR protocols for species discrimination of P. o. curtisi and P. o. wallikeri were carried out. Results were correlated with patient data on gender, age, travel destination, thrombocyte count, and duration of parasite latency. RESULTS Samples from 77 P. ovale spp. malaria patients were assessed, with a male:female ratio of about 2:1 and a median age of 30 years. Parasitaemia was low, ranging from few visible parasites up to 1% infected erythrocytes. Discriminative real-time PCRs revealed 41 cases of P. o. curtisi and 36 cases of P. o. wallikeri infections. Concordance of results by the two PCR approaches was 100%. Assessment of travel destinations confirmed co-existence of P. o. curtisi and P. o. wallikeri over a wide range of countries in sub-Saharan Africa. Latency periods for the two P. ovale species were similar, with median values of 56.0 days for P. o. curtisi and 58.0 days for P. o. wallikeri; likewise, there was no statistically significant difference in thrombocyte count with median values of 138.5/µL for patients with P. o. curtisi and 152.0/µL for P. o. wallikeri-infected patients. CONCLUSIONS Two different real-time PCR protocols were found to be suitable for the discrimination of P. o. curtisi and P. o. wallikeri with only minor differences in sensitivity. Due to the overall low parasitaemia and the lack of differences in severity-related aspects like parasite latency periods or thrombocyte counts, this study supports the use of P. ovale spp. PCR without discrimination on species level to confirm the diagnosis and to inform clinical management of malaria in these patients.
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Affiliation(s)
- Hagen Frickmann
- Department of Microbiology and Hospital Hygiene, External Site at the Bernhard Nocht Institute, Tropical Microbiology and Entomology, Bundeswehr Hospital Hamburg, Bernhard Nocht Str. 74, 20359, Hamburg, Germany. .,Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany.
| | - Christine Wegner
- Bernhard Nocht Institute for Tropical Medicine, National Reference Center for Tropical Pathogens, Hamburg, Germany
| | - Stefanie Ruben
- Bernhard Nocht Institute for Tropical Medicine, National Reference Center for Tropical Pathogens, Hamburg, Germany
| | - Ulrike Loderstädt
- Bernhard Nocht Institute for Tropical Medicine, National Reference Center for Tropical Pathogens, Hamburg, Germany
| | - Egbert Tannich
- Bernhard Nocht Institute for Tropical Medicine, National Reference Center for Tropical Pathogens, Hamburg, Germany
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