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Miezan AJS, Gnagne AP, Bedia-Tanoh AV, Kone EGM, Konate-Toure AA, Angora KE, Bosson-Vanga AH, Kassi KF, Kiki-Barro PCM, Djohan V, Menan HEI, Yavo W. Molecular epidemiology of non-falciparum Plasmodium infections in three different areas of the Ivory Coast. Malar J 2023; 22:211. [PMID: 37468917 DOI: 10.1186/s12936-023-04639-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
BACKGROUND Malaria is a major public health problem, particularly in the tropical regions of America, Africa and Asia. Plasmodium falciparum is not only the most widespread but also the most deadly species. The share of Plasmodium infections caused by the other species (Plasmodium ovale and Plasmodium malariae) is clearly underestimated. The objective of the study was to determine the molecular epidemiology of plasmodial infection due to P. malariae and P. ovale in Côte d'Ivoire. METHODS The study was cross-sectional. The study participants were recruited from Abengourou, San Pedro and Grand-Bassam. Sample collection took place from May 2015 to April 2016. Questionnaires were administered and filter paper blood samples were collected for parasite DNA extraction. The molecular analysis was carried out from February to March 2021. A nested PCR was used for species diagnosis. The data was presented in frequencies and proportions. RESULTS A total of 360 patients were recruited, including 179 men (49,7%) for 181 women (50,3%). The overall Plasmodium positive rate was 72.5% (261/360). The specific index was 77.4% and 1.5% for P. falciparum and P. malariae in mono-infection, respectively. There was also 15% P. falciparum and P. malariae co-infection, 3.4% P. falciparum and P. ovale co-infection and 2.3% P. falciparum, P. malariae and P. ovale triple-infection. Typing of P. ovale subspecies showed a significant predominance of P. ovale curtisi (81.2% of cases). CONCLUSION Plasmodium falciparum remains the most prevalent malaria species in Côte d'Ivoire, but P. malariae and P. ovale are also endemic mostly in co-infection. Malaria elimination requires a better understanding of the specific epidemiological characteristics of P. malariae and P. ovale with a particular emphasis on the identification of asymptomatic carriers.
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Affiliation(s)
- Assohoun J S Miezan
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire.
- National Institute of Public Health, B.P. V47, Abidjan, Côte d'Ivoire.
| | - Akpa P Gnagne
- National Institute of Public Health, B.P. V47, Abidjan, Côte d'Ivoire
| | - Akoua V Bedia-Tanoh
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
- National Institute of Public Health, B.P. V47, Abidjan, Côte d'Ivoire
| | - Estelle G M Kone
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
| | - Abibatou A Konate-Toure
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
- National Institute of Public Health, B.P. V47, Abidjan, Côte d'Ivoire
| | - Kpongbo E Angora
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
| | - Abo H Bosson-Vanga
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
| | - Kondo F Kassi
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
| | - Pulchérie C M Kiki-Barro
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
- National Institute of Public Health, B.P. V47, Abidjan, Côte d'Ivoire
| | - Vincent Djohan
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
| | - Hervé E I Menan
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
| | - William Yavo
- UFR of Pharmaceutical and Biological Sciences, Department of Parasitology-Mycology, Félix Houphouët-Boigny University, Abidjan, Côte d'Ivoire
- National Institute of Public Health, B.P. V47, Abidjan, Côte d'Ivoire
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Akinyi MY, Chifwete M, Ndwiga L, Kimenyi KM, Osoti V, Ochola-Oyier LI. A cross-sectional analysis identifies a low prevalence of Plasmodium ovale curtisi infections in symptomatic and asymptomatic individuals in Kilifi county, Kenya. Wellcome Open Res 2022. [DOI: 10.12688/wellcomeopenres.17972.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: The focus on P. falciparum diagnosis has led to an underestimation of the global burden of malaria resulting from neglected Plasmodium species. However, there is still scarce data on the prevalence of P. ovale globally. To address this knowledge gap, data collected from cross-sectional studies in Kilifi county were used to: 1) determine the prevalence of P. ovale curtisi infections; and 2) determine the sensitivity of different diagnostic assays in detecting P. ovale curtisi infections. Methods: A total of 531 individuals were sampled across three study sites in Kilifi County, Kenya between 2009 and 2020. Blood smears were prepared from peripheral blood and screened for Plasmodium parasite stages using light microscopy. Molecular screening involved DNA extraction of dried blood spots and blood in ethylenediaminetetraacetic acid, polymerase chain reaction (PCR) using primers targeting the 18 small ribosomal subunit and sequencing. Results: Microscopy screening revealed that the most prevalent species was P. falciparum (32.0%) followed by P. malariae (9.0%) and then P. ovale (1.5%). PCR screening identified additional P. ovale curtisi positives cases. Overall, 48 (8.2%) out of the 531 individuals harbored P. ovale curtisi infection with the highest prevalence reported in the tertiary health facility, (14.6%, 95% CI 8-23.6%), followed by the primary health facility (8.6%, 95% CI 5.4-11.9%), and the community from a cross-sectional blood survey, (6.5%, 95% CI 3.0-11.8%). Microscopy screening for P. ovale had a low sensitivity of 7% (95% CI 1-19-30%) and a high specificity of 99% (95% CI 98-100%). Sequencing results confirmed the presence of P.ovale curtisi. Conclusions: This study provides baseline data for P.ovale curtisi surveillance in Kilifi County, primarily using PCR to improve diagnosis. These results suggest that malaria elimination and eradication efforts should not only concentrate on P. falciparum but should embrace a holistic approach towards elimination of all Plasmodium species.
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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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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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Epidemiological, Physiological and Diagnostic Comparison of Plasmodium ovale curtisi and Plasmodium ovale wallikeri. Diagnostics (Basel) 2021; 11:diagnostics11101900. [PMID: 34679597 PMCID: PMC8534334 DOI: 10.3390/diagnostics11101900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 08/05/2021] [Accepted: 08/06/2021] [Indexed: 11/17/2022] Open
Abstract
Nowadays, Plasmodium ovale is divided into two non-recombinant sympatric species: Plasmodium ovale wallikeri and Plasmodium ovale curtisi. In this mini review, we summarize the available knowledge on the clinical/biological aspects of P. ovale spp. malaria and current techniques for the diagnosis/characterisation of P. ovale curtisi and P. ovale wallikeri. P. ovale wallikeri infections are characterized by a deeper thrombocytopenia and shorter latency compared to P. ovale curtisi infections, indicating that P. ovale wallikeri is more pathogenic than P. ovale curtisi. Rapid diagnosis for effective management is difficult for P. ovale spp., since specific rapid diagnostic tests are not available and microscopic diagnosis, which is recognized as the gold standard, requires expert microscopists to differentiate P. ovale spp. from other Plasmodium species. Neglect in addressing these issues in the prevalence of P. ovale spp. represents the existing gap in the fight against malaria.
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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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Oyedeji SI, Awobode HO, Ojurongbe O, Anumudu C, Bassi PU. Molecular Identification and Characterization of Plasmodium ovale curtisi in Field Isolates from Symptomatic Children in North-Central Nigeria. Acta Parasitol 2021; 66:915-924. [PMID: 33710479 DOI: 10.1007/s11686-021-00350-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 02/10/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE Plasmodium ovale is not usually the focus of most malaria research or intervention programmes and has lately been termed the neglected human malaria parasites. The parasite exists as two genetically distinct sympatric species namely P. ovale curtisi and P. ovale wallikeri but information on the distribution of P. ovale sub-species is lacking in Nigeria. The objective of this study, therefore, was aimed at characterizing the P. ovale sub-species in isolates from symptomatic individuals in North-central Nigeria. METHODS Parasites were identified by light microscopy of Giemsa stained thick and thin blood films. Molecular characterization and confirmation of P. ovale sub-species were done by species-specific nested PCR and sequencing of the small subunit ribosomal RNA (SSUrRNA) gene. RESULTS A total of 412 children were enrolled into this study of which 88.6% (n = 365) were positive for Plasmodium species by nested PCR and P. falciparum was predominant. Of the 365 isolates, 4 (1.1%) had P. ovale infections and of these, 3 (0.8%) were mixed species infections of P. ovale with P. falciparum. DNA sequence analysis confirmed that all the four P. ovale parasites were P. ovale curtisi as their sequences were 99-100% identical to previously published P. ovale curtisi sequences in the GenBank and they cluster with the P. ovale curtisi sequences by phylogeny. CONCLUSION Our findings demonstrate the occurrence of P. ovale curtisi in the study area. This has implications for public health and malaria elimination programmes, since they also serve as potential risk to travellers from malaria-free regions.
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Affiliation(s)
- Segun Isaac Oyedeji
- Molecular Parasitology and Genetics Unit, Department of Animal and Environmental Biology, Federal University Oye-Ekiti, Oye-Ekiti, Nigeria.
| | | | - Olusola Ojurongbe
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University of Technology, Osogbo, Nigeria
| | - Chiaka Anumudu
- Parasitology Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
| | - Peter Usman Bassi
- Department of Clinical Pharmacology and Therapeutics, University of Abuja, Abuja, Nigeria
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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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Gimenez AM, Marques RF, Regiart M, Bargieri DY. Diagnostic Methods for Non-Falciparum Malaria. Front Cell Infect Microbiol 2021; 11:681063. [PMID: 34222049 PMCID: PMC8248680 DOI: 10.3389/fcimb.2021.681063] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/31/2021] [Indexed: 11/13/2022] Open
Abstract
Malaria is a serious public health problem that affects mostly the poorest countries in the world, killing more than 400,000 people per year, mainly children under 5 years old. Among the control and prevention strategies, the differential diagnosis of the Plasmodium-infecting species is an important factor for selecting a treatment and, consequently, for preventing the spread of the disease. One of the main difficulties for the detection of a specific Plasmodium sp is that most of the existing methods for malaria diagnosis focus on detecting P. falciparum. Thus, in many cases, the diagnostic methods neglect the other non-falciparum species and underestimate their prevalence and severity. Traditional methods for diagnosing malaria may present low specificity or sensitivity to non-falciparum spp. Therefore, there is high demand for new alternative methods able to differentiate Plasmodium species in a faster, cheaper and easier manner to execute. This review details the classical procedures and new perspectives of diagnostic methods for malaria non-falciparum differential detection and the possibilities of their application in different circumstances.
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Affiliation(s)
- Alba Marina Gimenez
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rodolfo F. Marques
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Matías Regiart
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Daniel Youssef Bargieri
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Kifude C, Stiffler D, Rockabrand D, Miller R, Parsons E, Ocholla S, Dizon NI, Torrevillas BK, Waitumbi J, Oyieko J, Luckhart S, Stewart VA. Asymptomatic falciparum and Non-falciparum Malarial Parasitemia in Adult Volunteers with and without HIV-1 Coinfection in a Cohort Study in Western Kenya. Am J Trop Med Hyg 2021; 105:159-166. [PMID: 34097645 DOI: 10.4269/ajtmh.21-0012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/19/2021] [Indexed: 11/07/2022] Open
Abstract
Asymptomatic malarial parasitemia represents the largest reservoir of infection and transmission, and the impact of coinfection with HIV-1 on this reservoir remains incompletely described. Accordingly, we sought to determine the prevalence of asymptomatic malarial parasitemia in Kombewa, Western Kenya, a region that is endemic for both malaria and HIV-1. A total of 1,762 dried blood spots were collected from asymptomatic adults in a cross-sectional study. The presence of parasitemia was first determined by a sensitive Plasmodium genus-specific 18S assay, followed by less sensitive species-specific DNA-based quantitative polymerase chain reaction (PCR) assays. The prevalence of asymptomatic malarial parasitemia by 18S genus-specific PCR assay was 64.4% (1,134/1,762). Of the 1,134 malaria positive samples, Plasmodium falciparum was the most prevalent species (57.4%), followed by Plasmodium malariae (3.8%) and Plasmodium ovale (2.6%) as single or mixed infections. As expected, the majority of infections were below the detection limit of microscopy and rapid diagnostic tests. HIV-1 prevalence was 10.6%, and we observed a significant association with malarial parasitemia by χ2 analysis (P = 0.0475). Seventy-one percent of HIV-1 infected volunteers were positive for Plasmodium 18S (132/186), with only 29% negative (54/186). In HIV-1-negative volunteers, the proportion was lower; 64% were found to be positive for 18S (998/1,569) and 36% were negative (571/1,569). Overall, the prevalence of asymptomatic malarial parasitemia in Western Kenya is high, and knowledge of these associations with HIV-1 infection are critically important for malaria elimination and eradication efforts focused on this important reservoir population.
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Affiliation(s)
- Carolyne Kifude
- 1Basic Science Laboratory, U.S. Army Medical Research Directorate-Africa/Kenya Medical Research Institute, Kisumu, Kenya
| | - Deborah Stiffler
- 2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - David Rockabrand
- 2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Robin Miller
- 2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Emily Parsons
- 1Basic Science Laboratory, U.S. Army Medical Research Directorate-Africa/Kenya Medical Research Institute, Kisumu, Kenya.,2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Stephen Ocholla
- 1Basic Science Laboratory, U.S. Army Medical Research Directorate-Africa/Kenya Medical Research Institute, Kisumu, Kenya
| | - Nathaniel I Dizon
- 2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Brandi K Torrevillas
- 3Department of Entomology, Plant Pathology and Nematology, University of Idaho, Moscow, Idaho
| | - John Waitumbi
- 1Basic Science Laboratory, U.S. Army Medical Research Directorate-Africa/Kenya Medical Research Institute, Kisumu, Kenya
| | - Janet Oyieko
- 1Basic Science Laboratory, U.S. Army Medical Research Directorate-Africa/Kenya Medical Research Institute, Kisumu, Kenya
| | - Shirley Luckhart
- 3Department of Entomology, Plant Pathology and Nematology, University of Idaho, Moscow, Idaho.,4Department of Biological Sciences, University of Idaho, Moscow, Idaho
| | - V Ann Stewart
- 2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
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Chen X, Zhang J, Pan M, Qin Y, Zhao H, Qin P, Yang Q, Li X, Zeng W, Xiang Z, Duan M, Li X, Wang X, Mazier D, Zhang Y, Zhao W, Rosenthal BM, Huang Y, Yang Z. Loop-mediated isothermal amplification (LAMP) assays targeting 18S ribosomal RNA genes for identifying P. vivax and P. ovale species and mitochondrial DNA for detecting the genus Plasmodium. Parasit Vectors 2021; 14:278. [PMID: 34030725 PMCID: PMC8147439 DOI: 10.1186/s13071-021-04764-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 05/03/2021] [Indexed: 11/18/2022] Open
Abstract
Background Loop-mediated isothermal amplification (LAMP) has been widely used to diagnose various infectious diseases. Malaria is a globally distributed infectious disease attributed to parasites in the genus Plasmodium. It is known that persons infected with Plasmodium vivax and P. ovale are prone to clinical relapse of symptomatic blood-stage infections. LAMP has not previously been specifically evaluated for its diagnostic performance in detecting P. ovale in an epidemiological study, and no commercial LAMP or rapid diagnostic test (RDT) kits are available for specifically diagnosing infections with P. ovale. Methods An assay was designed to target a portion of mitochondrial DNA (mtDNA) among Plasmodium spp., the five human Plasmodium species and two other assays were designed to target the nuclear 18S ribosomal DNA gene (18S rDNA) of either P. vivax or P. ovale for differentiating the two species. The sensitivity of the assays was compared to that of nested PCR using defined concentrations of plasmids containing the target sequences and using limiting dilutions prepared from clinical isolates derived from Chinese workers who had become infected in Africa or near the Chinese border with Myanmar. Results The results showed that 102 copies of the mitochondrial target or 102 and 103 copies of 18S rDNA could be detected from Plasmodium spp., P. vivax and P. ovale, respectively. In 279 clinical samples, the malaria Pan mtDNA LAMP test performed well when compared with a nested PCR assay (95% confidence interval [CI] sensitivity 98.48–100%; specificity 90.75–100%). When diagnosing clinical cases of infection with P. vivax, the 18S rDNA assay demonstrated an even great sensitivity (95.85–100%) and specificity (98.1–100%). The same was true for clinical infections with P. ovale (sensitivity 90.76–99.96%; specificity 98.34–100%). Using plasmid-positive controls, the limits of detection of Malaria Pan, 18S rDNA P. vivax and 18S rDNA P. ovale LAMP were 100-, 100- and tenfold lower than those of PCR, respectively. Conclusion The novel LAMP assays can greatly aid the rapid, reliable and highly sensitive diagnosis of infections of Plasmodium spp. transmitted among people, including P. vivax and P. ovale, cases of which are most prone to clinical relapse. Graphic abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04764-9.
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Affiliation(s)
- Xi Chen
- Laboratory of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China.,Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Jiaqi Zhang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China.,Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 BinSheng Road, Binjiang District, Hangzhou, 310051, Zhejiang, People's Republic of China
| | - Maohua Pan
- Shanglin County People's Hospital, Shanglin, 530500, Guangxi, People's Republic of China
| | - Yucheng Qin
- Shanglin County People's Hospital, Shanglin, 530500, Guangxi, People's Republic of China
| | - Hui Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Pien Qin
- Shanglin County People's Hospital, Shanglin, 530500, Guangxi, People's Republic of China
| | - Qi Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Xinxin Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Weilin Zeng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Zheng Xiang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Mengxi Duan
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Xiaosong Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Xun Wang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Dominique Mazier
- INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI), Sorbonne Université, 75013, Paris, France
| | - Yanmei Zhang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Wei Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China
| | - Benjamin M Rosenthal
- Animal Parasitic Disease Laboratory, USDA-Agricultural Research Service, 10300 Baltimore Avenue, Beltsville, MD, 20705, USA
| | - Yaming Huang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China. .,Guangxi Zhuang Autonomous Region Center for Disease Prevention and Control, Nanning, 530021, Guangxi, People's Republic of China.
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, 650500, Yunnan, People's Republic of China.
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12
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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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13
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Xie Y, Wu K, Cheng W, Jiang T, Yao Y, Xu M, Yang Y, Tan H, Li J. Molecular epidemiological surveillance of Africa and Asia imported malaria in Wuhan, Central China: comparison of diagnostic tools during 2011-2018. Malar J 2020; 19:321. [PMID: 32883296 PMCID: PMC7470674 DOI: 10.1186/s12936-020-03387-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 08/25/2020] [Indexed: 01/17/2023] Open
Abstract
Background Malaria remains a serious public health problem globally. As the elimination of indigenous malaria continues in China, imported malaria has gradually become a major health hazard. Well-timed and accurate diagnoses could support the timely implementation of therapeutic schedules, reveal the prevalence of imported malaria and avoid transmission of the disease. Methods Blood samples were collected in Wuhan, China, from August 2011 to December 2018. All patients accepted microscopy and rapid diagnosis test (RDT) examinations. Subsequently, each of the positive or suspected positive cases was tested for four human-infectious Plasmodium species by using 18S rRNA-based nested PCR and Taqman probe-based real-time PCR. The results of the microscopy and the two molecular diagnostic methods were analysed. Importation origins were traced by country, and the prevalence of Plasmodium species was analysed by year. Results A total of 296 blood samples, including 288 that were microscopy and RDT positive, 7 RDT and Plasmodium falciparum positive, and 1 suspected case, were collected and reanalysed. After application of the two molecular methods and sequencing, 291 cases including 245 P. falciparum, 15 Plasmodium vivax, 20 Plasmodium ovale, 6 Plasmodium malariae and 5 mixed infections (3 P. falciparum + P. ovale, 2 P. vivax + P. ovale) were confirmed. These patients had returned from Africa (95.53%) and Asia (4.47%). Although the prevalence displayed a small-scale fluctuation, the overall trend of the imported cases increased yearly. Conclusions These results emphasize the necessity of combined utilization of the four tools for malaria diagnosis in clinic and in field surveys of potential risk regions worldwide including Wuhan.
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Affiliation(s)
- Yiting Xie
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Kai Wu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Weijia Cheng
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Tingting Jiang
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Yi Yao
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Mingxing Xu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Yan Yang
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Huabing Tan
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Jian Li
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China. .,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.
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14
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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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15
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Liew JWK, Ooi CH, Snounou G, Lau YL. Case Report: Two Cases of Recurring Ovale Malaria in Sarawak, Malaysia, after Successful Treatment of Imported Plasmodium falciparum Infection. Am J Trop Med Hyg 2020; 101:1402-1404. [PMID: 31595863 DOI: 10.4269/ajtmh.19-0305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Here are two cases of recurring ovale malaria in Sarawak, Malaysia, that are likely relapses that occurred 1-2 months after successful treatment of the initial imported falciparum malaria with artemisinin-based combined therapy. The patients have no history or recollection of previous malaria episodes. These cases add to the limited evidence on the relapsing nature of Plasmodium ovale, after a febrile episode. In regions where P. ovale is not known to be autochthonous, active follow-up of treated imported malaria patients is highly recommended following their return, particularly to areas nearing or having achieved elimination.
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Affiliation(s)
- Jonathan Wee Kent Liew
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Huck Ooi
- Vector Borne Diseases Section, Sarawak Health Department, Kuching, Malaysia
| | - Georges Snounou
- CEA-Université Paris Sud 11-INSERM U1184, Immunology of Viral Infections and Autoimmune Diseases (IMVA), Infectious Disease Models and Innovative Therapies (IDMIT) Department, Institut de Biologie François Jacob (IBFJ), Direction de la Recherche Fondamentale (DRF), Fontenay-aux-Roses, France
| | - Yee Ling Lau
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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16
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Nawaz M, Malik I, Hameed M, Hussain Kuthu Z, Zhou J. Modifications of histones in parasites as drug targets. Vet Parasitol 2020; 278:109029. [PMID: 31978703 DOI: 10.1016/j.vetpar.2020.109029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 02/06/2023]
Abstract
Post-translational modifications of histones and histone modifying enzymes play important roles in gene regulations and other physiological processes in parasites. Inhibitors of such modifying enzymes could be useful as novel therapeutics against parasitic diseases or as chemical probes for investigation of epigenetics. Development of parasitic histone modulators has got rapid expansion in the last few years. A number of highly potent and selective compounds have been reported, together with extensive preclinical studies of their biological activity. Some of these compounds have been widely used in humans targeting cancer and are found non-toxic. This review summarizes the antiparasitic activities of histone and histone modifying enzymes inhibitors evaluated in last few years. As the current chemotherapy against parasites is still not satisfactory, therefore, such compounds represents good starting points for the discovery of effective antiparasitic drugs.
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Affiliation(s)
- Mohsin Nawaz
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Irfan Malik
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Mudassar Hameed
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Zulfiqar Hussain Kuthu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Jinlin Zhou
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China.
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17
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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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18
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Kamaliddin C, Le Bouar M, Berry A, Fenneteau O, Gillet P, Godineau N, Candolfi E, Houzé S. Assessment of diagnostic methods for imported malaria in mainland France. Med Mal Infect 2019; 50:141-160. [PMID: 31375372 DOI: 10.1016/j.medmal.2019.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 07/04/2019] [Indexed: 12/29/2022]
Affiliation(s)
- C Kamaliddin
- Centre national de référence du paludisme, hôpital Bichat, 75018 Paris, France
| | - M Le Bouar
- Service de parasitologie-mycologie, CHU de Toulouse, 31300 Toulouse, France
| | - A Berry
- Service de parasitologie-mycologie, CHU de Toulouse, 31300 Toulouse, France
| | - O Fenneteau
- Service d'hématologie biologique, CHU Robert-Debré, AP-HP, 75018 Paris, France
| | - P Gillet
- Department of clinical sciences, institute of tropical medicine, 2000 Anvers, Belgium
| | - N Godineau
- Service de parasitologie, centre hospitalier Delafontaine, 93200 Saint-Denis, France
| | - E Candolfi
- Laboratoire de parasitologie, institut de parasitologie et de pathologie tropicale, hôpitaux civils de Strasbourg, CHU, 67000 Strasbourg, France
| | - S Houzé
- Centre national de référence du paludisme, hôpital Bichat, 75018 Paris, France; Service de parasitologie, hôpital Bichat, AP-HP, 75018 Paris, France.
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19
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Frickmann H, Wegner C, Ruben S, Behrens C, Kollenda H, Hinz R, Rojak S, Schwarz NG, Hagen RM, Tannich E. Evaluation of the multiplex real-time PCR assays RealStar malaria S&T PCR kit 1.0 and FTD malaria differentiation for the differentiation of Plasmodium species in clinical samples. Travel Med Infect Dis 2019; 31:101442. [PMID: 31255712 DOI: 10.1016/j.tmaid.2019.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 06/20/2019] [Accepted: 06/26/2019] [Indexed: 12/28/2022]
Abstract
BACKGROUND Two commercial PCR assays were assessed in a retrospective study to determine their reliability as tools for the differentiation of Plasmodium species in human blood. METHODS A total of 1022 blood samples from 817 patients with suspected or confirmed malaria submitted to the German National Reference Centre for Tropical Pathogens were subjected to malaria microscopy using thick and thin blood films as well as to a genus-specific malaria real-time PCR. Parasite-positive samples were analysed by RealStar Malaria S&T PCR Kit 1.0 (altona Diagnostics) and FTD Malaria Differentiation (Fast Track Diagnostics) multiplex real-time PCR assays targeting species-specific Plasmodium DNA. RESULTS Out of the 1022 blood samples, 247 (24.2%) tested positive for Plasmodium spp. The two multiplex assays showed rather similar performance characteristics and provided concordant species information in 98.9% of samples positive by malaria microscopy and in 95.1% (RealStar) and 96.8% (FTD) of samples positive by genus-specific PCR. Compared to FTD, RealStar revealed slightly reduced sensitivity for submicroscopic, low-level P. falciparum infections, while FTD was unable to detect P. knowlesi. CONCLUSIONS The two commercial malaria PCR assays assessed are suitable for discriminating Plasmodium species in clinical samples, and can provide additional information in cases of microscopically uncertain findings.
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Affiliation(s)
- Hagen Frickmann
- Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany; Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany.
| | - Christine Wegner
- National Reference Centre for Tropical Pathogens, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Stefanie Ruben
- National Reference Centre for Tropical Pathogens, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Christoph Behrens
- National Reference Centre for Tropical Pathogens, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Hans Kollenda
- Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | - Rebecca Hinz
- Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | - Sandra Rojak
- Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany; Department of Infectious Diseases and Tropical Medicine, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | - Norbert G Schwarz
- Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Ralf Matthias Hagen
- Department of Preventive Medicine, Bundeswehr Medical Academy, Munich, Germany
| | - Egbert Tannich
- National Reference Centre for Tropical Pathogens, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
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20
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Schindler T, Jongo S, Studer F, Mpina M, Mwangoka G, Mswata S, Ramadhani K, Sax J, Church LWP, Richie TL, Tanner M, Hoffman SL, Abdulla S, Daubenberger C. Two cases of long-lasting, sub-microscopic Plasmodium malariae infections in adults from coastal Tanzania. Malar J 2019; 18:149. [PMID: 31036014 PMCID: PMC6489319 DOI: 10.1186/s12936-019-2787-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/22/2019] [Indexed: 01/29/2023] Open
Abstract
Background Malaria is endemic in Tanzania with majority of clinical cases caused by Plasmodium falciparum. Additionally, Plasmodium malariae and Plasmodium ovale spp. are also present and clinical manifestations caused by these infections are not well described. Clinical episodes caused by P. malariae infections are often characterized by a relatively mild illness with a low number of parasites, which can persist for long periods. In this report, two cases of P. malariae infections that were identified during a clinical trial evaluating the P. falciparum malaria vaccine candidate, PfSPZ Vaccine are described. The two participants were followed up and monitored for clinical and laboratory parameters to assess vaccine safety providing the opportunity to study clinical manifestations of P. malariae over 4 months. Case presentation Two young, healthy Tanzanian men infected with low density asexual blood stage P. malariae diagnosed by quantitative polymerase chain reaction (qPCR) are described. Retrospective analysis of collected and stored blood samples revealed that the two volunteers had constant asexual blood stage parasitaemia for more than 4 months. During the 132 days of infection, the volunteers’ vital signs, body temperature and serum biochemistry all remained within normal ranges. Haematological abnormalities, which were transiently outside normal ranges, were regarded as not clinically significant. During this time period, four consecutive evaluations of blood samples by thick blood smear microscopy conducted by an experienced microscopist were all negative, indicating the presence of low-density sub-microscopic infections. Conclusions The two cases of P. malariae infections presented here confirm the ability of this Plasmodium species to persist at low density in the human host for extended time periods without causing clinical symptoms. The presented data also demonstrate that clinical study sites in malaria endemic regions need to have a strong malaria diagnostic infrastructure, including the ability of capturing sub-microscopic parasitaemia and differentiation of Plasmodium species. Trial registration ClinicalTrials.gov: NCT02613520, https://clinicaltrials.gov/ct2/show/NCT02613520, Registered: November 24th 2015, Enrolment of the first participant to the trial: December 15th 2015, Trial was registered before the first participant was enrolled
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Affiliation(s)
- Tobias Schindler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Said Jongo
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, United Republic of Tanzania.
| | - Fabian Studer
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Maximilian Mpina
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland.,Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, United Republic of Tanzania
| | - Grace Mwangoka
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, United Republic of Tanzania
| | - Sarah Mswata
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, United Republic of Tanzania
| | - Kamaka Ramadhani
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, United Republic of Tanzania
| | - Julian Sax
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | | | - Marcel Tanner
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Salim Abdulla
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, United Republic of Tanzania
| | - Claudia Daubenberger
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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21
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Lamien-Meda A, Fuehrer HP, Noedl H. Novel high resolution melting (HRM) and snapback assays for simultaneous detection and differentiation of Plasmodium ovale spp. Acta Trop 2019; 192:75-81. [PMID: 30711423 DOI: 10.1016/j.actatropica.2019.01.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 01/18/2019] [Accepted: 01/18/2019] [Indexed: 12/16/2022]
Abstract
Plasmodium ovale spp. are two of the six species of apicomplexan parasites belonging to the genus Plasmodium commonly causing disease in humans. A recent phylogeny study has identified both Plasmodium ovale species (P. ovale curtisi and P. ovale wallikeri) as two sympatric occurring species. The actual prevalence and clinical relevance of P. ovale spp. are likely underestimated due to low parasitemia and mixed infections, which pose a major challenge to microscopic diagnosis and are frequently undetectable using malaria Rapid Diagnostic Tests (RDTs). The aim of this work is to develop a HRM-based assay for simultaneous detection and differentiation of P. ovale wallikeri and P. ovale curtisi. Thirty three well-documented P. ovale spp. samples from previous studies were used for this study. The newly developed High Resolution Melting (HRM) assay targeting the apicoplast genome was highly specific to both P. ovale species. Adding a snapback tail at the 5' end of the forward primer for a nested HRM PCR, increased the melting temperature (Tm) difference between the two species. To our knowledge this study reports the first direct HRM assay developed on the apicoplast genome, specific for both P. ovale species. This method provides added value to the WHO open request of developing new practical malaria diagnostic methods for the malaria elimination program and could contribute to a quick and efficient diagnosis of low-level parasitemia, symptomatic or asymptomatic, as well as mixed or single P. ovale infections.
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Affiliation(s)
- Aline Lamien-Meda
- Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Austria.
| | - Hans-Peter Fuehrer
- Institute of Parasitology, University of Veterinary Medicine, Vienna, Austria
| | - Harald Noedl
- Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Austria
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22
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Schindler T, Robaina T, Sax J, Bieri JR, Mpina M, Gondwe L, Acuche L, Garcia G, Cortes C, Maas C, Daubenberger C. Molecular monitoring of the diversity of human pathogenic malaria species in blood donations on Bioko Island, Equatorial Guinea. Malar J 2019; 18:9. [PMID: 30646918 PMCID: PMC6332537 DOI: 10.1186/s12936-019-2639-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 01/08/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria can be transmitted by blood transfusion from human to human and it is responsible for the majority of transfusion-transmitted infectious diseases worldwide. In sub-Saharan Africa, it had been estimated that almost a quarter of blood donations contain malaria parasites. Since rapid diagnostic tests and thick blood smear microscopy lack sensitivity for low density parasitaemia, particularly in asymptomatic adults, the most reliable method to assess the problem of transfusion-transmitted malaria are nucleic acid-based molecular approaches such as quantitative polymerase chain reaction. The study was undertaken to determine the prevalence of sub-microscopic malaria parasite infection among blood donors in Malabo, Equatorial Guinea. METHODS Between July and August 2017, a total of 200 individual blood samples from blood donors at the Malabo Blood Bank were collected and screened by rapid diagnostic tests and thick blood smear microscopy. Retrospectively, the same samples were analysed for the presence of undetected, low-density malaria parasites using quantitative polymerase chain reaction. RESULTS In comparison to 6.5% (13/200) by rapid diagnostic test and 2.0% (4/200) by microscopy, the proportion of Plasmodium falciparum positive blood donations analysed by quantitative polymerase chain reaction was significantly higher (26%, 52/200). Densities of P. falciparum positive blood donations were ranging from 0.06 to 3707.0 parasites/µL with 79.6% below 100 parasites/µL and therefore not detectable by non-molecular malaria diagnostic tests. qPCR based species identification revealed that P. falciparum was the dominating species responsible for 88.1% (52/59) of positive blood donations, followed by Plasmodium malariae (15.3%, 9/59) and Plasmodium ovale (3.4%, 2/59). CONCLUSIONS This study confirms that in malaria endemic settings, sub-patent malaria infections among blood donors are prevalent. In blood collected from healthy donors living in Malabo, P. falciparum, P. malariae and P. ovale parasites were identified. Currently widely used malaria diagnostic tools have missed more than 75% of P. falciparum containing blood donations, demonstrating the value of quantitative polymerase chain reaction to reliably detect low density P. falciparum infections. Since the availability of molecular diagnostic methods in malaria endemic countries is still limited, the blood recipients living in malaria endemic countries should be treated following WHO recommendations.
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Affiliation(s)
- Tobias Schindler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | | | - Julian Sax
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jose Raso Bieri
- Equatorial Guinea Malaria Vaccine Initiative, Malabo, Equatorial Guinea
| | - Maximilian Mpina
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland.,Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Linda Gondwe
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland.,Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Ludmila Acuche
- Equatorial Guinea Malaria Vaccine Initiative, Malabo, Equatorial Guinea
| | | | - Carlos Cortes
- Medical Care Development International, Silver Spring, USA
| | - Carl Maas
- Marathon EG Production Ltd, Malabo, Equatorial Guinea
| | - Claudia Daubenberger
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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23
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Rojo-Marcos G, Rubio-Muñoz JM, Angheben A, Jaureguiberry S, García-Bujalance S, Tomasoni LR, Rodríguez-Valero N, Ruiz-Giardín JM, Salas-Coronas J, Cuadros-González J, García-Rodríguez M, Molina-Romero I, López-Vélez R, Gobbi F, Calderón-Moreno M, Martin-Echevarría E, Elía-López M, Llovo-Taboada J. Prospective comparative multi-centre study on imported Plasmodium ovale wallikeri and Plasmodium ovale curtisi infections. Malar J 2018; 17:399. [PMID: 30376868 PMCID: PMC6208040 DOI: 10.1186/s12936-018-2544-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 10/22/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Few previous retrospective studies suggest that Plasmodium ovale wallikeri seems to have a longer latency period and produces deeper thrombocytopaenia than Plasmodium ovale curtisi. Prospective studies were warranted to better assess interspecies differences. METHODS Patients with imported P. ovale spp. infection diagnosed by thick or thin film, rapid diagnostic test (RDT) or polymerase chain reaction (PCR) were recruited between March 2014 and May 2017. All were confirmed by DNA isolation and classified as P. o. curtisi or P. o. wallikeri using partial sequencing of the ssrRNA gene. Epidemiological, analytical and clinical differences were analysed by statistical methods. RESULTS A total of 79 samples (35 P. o. curtisi and 44 P. o. wallikeri) were correctly genotyped. Males predominate in wallikeri group (72.7%), whereas were 48.6% in curtisi group. Conversely, 74.3% of curtisi group were from patients of African ethnicity, whilst 52.3% of Caucasians were infected by P. o. wallikeri. After performing a multivariate analysis, more thrombocytopaenic patients (p = 0.022), a lower number of platelets (p = 0.015), a higher INR value (p = 0.041), and shorter latency in Caucasians (p = 0.034) were significantly seen in P. o. wallikeri. RDT sensitivity was 26.1% in P. o. curtisi and 42.4% in P. o. wallikeri. Nearly 20% of both species were diagnosed only by PCR. Total bilirubin over 3 mg/dL was found in three wallikeri cases. Two patients with curtisi infection had haemoglobin under 7 g/dL, one of them also with icterus. A wallikeri patient suffered from haemophagocytosis. Chemoprophylaxis failed in 14.8% and 35% of curtisi and wallikeri patients, respectively. All treated patients with various anti-malarials which included artesunate recovered. Diabetes mellitus was described in 5 patients (6.32%), 4 patients of wallikeri group and 1 curtisi. CONCLUSIONS Imported P. o. wallikeri infection may be more frequent in males and Caucasians. Malaria caused by P. o. wallikeri produces more thrombocytopaenia, a higher INR and shorter latency in Caucasians and suggests a more pathogenic species. Severe cases can be seen in both species. Chemoprophylaxis seems less effective in P. ovale spp. infection than in P. falciparum, but any anti-malarial drug is effective as initial treatment. Diabetes mellitus could be a risk factor for P. ovale spp. infection.
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Affiliation(s)
- Gerardo Rojo-Marcos
- Hospital Universitario Príncipe de Asturias, Ctra de Meco s/n, 28805, Alcalá de Henares, Madrid, Spain.
| | | | | | - Stephane Jaureguiberry
- Hôpital Pitié-Salpêtrière, Assistance Publique des Hôpitaux de Paris (APHP), Paris, France
| | | | | | | | | | | | - Juan Cuadros-González
- Hospital Universitario Príncipe de Asturias, Ctra de Meco s/n, 28805, Alcalá de Henares, Madrid, Spain
| | | | | | | | - Federico Gobbi
- Ospedale Sacro Cuore - Don Calabria, Negrar, Verona, Italy
| | | | | | | | - José Llovo-Taboada
- Complejo Hospitalario Universitario de Santiago de Compostela, A Coruña, Spain
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24
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Joste V, Kamaliddin C, Kendjo E, Hubert V, Argy N, Houzé S. Distinction of Plasmodium ovale wallikeri and Plasmodium ovale curtisi using quantitative Polymerase Chain Reaction with High Resolution Melting revelation. Sci Rep 2018; 8:300. [PMID: 29321578 PMCID: PMC5762660 DOI: 10.1038/s41598-017-18026-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 11/28/2017] [Indexed: 11/22/2022] Open
Abstract
Plasmodium ovale curtisi (Poc) and Plasmodium ovale wallikeri (Pow) have been described as two distinct species, only distinguishable by molecular methods such as PCR. Because of no well-defined endemic area and a variable clinical presentation as higher thrombocytopenia and nausea associated with Pow infection and asymptomatic forms of the pathology with Poc infection, rapid and specific identification of Plasmodium ovale curtisi and Plasmodium ovale wallikeri are needed. The aim of the study was to evaluate a new quantitative real-time PCR coupled with high resolution melting revelation (qPCR-HRM) for identification of both species. Results were compared with a nested-PCR, considered as a gold standard for Pow and Poc distinction. 356 samples including all human Plasmodium species at various parasitaemia were tested. The qPCR-HRM assay allowed Poc and Pow discrimination in 66 samples tested with a limit of detection evaluated at 1 parasite/µL. All these results were concordant with nested-PCR. Cross-reaction was absent with others blood parasites. The qPCR-HRM is a rapid and convenient technique to Poc and Pow distinction.
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Affiliation(s)
- V Joste
- National French Malaria Reference Center, Bichat-Claude Bernard Hospital, 75018, Paris, France.
- Parasitology and Mycology Laboratory, Bichat-Claude Bernard Hospital, APHP, 75018, Paris, France.
| | - C Kamaliddin
- National French Malaria Reference Center, Bichat-Claude Bernard Hospital, 75018, Paris, France
- UMR216- MERIT, COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris, 75006, France
| | - E Kendjo
- National French Malaria Reference Center, Bichat-Claude Bernard Hospital, 75018, Paris, France
- National French Malaria Reference Center, Pitié Salpetrière hospital, 75013, Paris, France
| | - V Hubert
- National French Malaria Reference Center, Bichat-Claude Bernard Hospital, 75018, Paris, France
- UMR216- MERIT, COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris, 75006, France
| | - N Argy
- National French Malaria Reference Center, Bichat-Claude Bernard Hospital, 75018, Paris, France
- Parasitology and Mycology Laboratory, Bichat-Claude Bernard Hospital, APHP, 75018, Paris, France
- UMR216- MERIT, COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris, 75006, France
| | - S Houzé
- National French Malaria Reference Center, Bichat-Claude Bernard Hospital, 75018, Paris, France
- Parasitology and Mycology Laboratory, Bichat-Claude Bernard Hospital, APHP, 75018, Paris, France
- UMR216- MERIT, COMUE Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris Descartes University, Paris, 75006, France
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25
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Katrak S, Murphy M, Nayebare P, Rek J, Smith M, Arinaitwe E, Nankabirwa JI, Kamya M, Dorsey G, Rosenthal PJ, Greenhouse B. Performance of Loop-Mediated Isothermal Amplification for the Identification of Submicroscopic Plasmodium falciparum Infection in Uganda. Am J Trop Med Hyg 2017; 97:1777-1781. [PMID: 29016335 PMCID: PMC5805042 DOI: 10.4269/ajtmh.17-0225] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Accurately identifying and targeting the human reservoir of malaria parasitemia is critical for malaria control, and requires a reliable and sensitive diagnostic method. Loop-mediated isothermal amplification (LAMP) is increasingly used to diagnose submicroscopic parasitemia. Although most published studies report the sensitivity of LAMP compared with nested polymerase chain reaction (PCR) as ≥ 80%, they have failed to use a consistent, sensitive diagnostic as a comparator. We used cross-sectional samples from children and adults in Tororo, Uganda, a region with high but declining transmission due to indoor residual spraying, to characterize the sensitivity and specificity of pan-Plasmodium LAMP for detecting submicroscopic infections. We compared LAMP results targeting a mitochondrial DNA sequence conserved in all Plasmodium species, performed on DNA extracted from dried blood spots, to those of a gold standard quantitative PCR assay targeting the var gene acidic terminal sequence of Plasmodium falciparum (varATS qPCR), performed on DNA extracted from 200 µL of whole blood. Using LAMP and varATS qPCR increased the detection of parasitemia 2- to 5-fold, compared with microscopy. Among microscopy-negative samples, the sensitivity of LAMP was 81.5% for detecting infection ≥ 1 parasites/µL. However, low density infections were common, and LAMP failed to identify more than half of all infections diagnosed by varATS qPCR, performing with an overall sensitivity of 44.7% for detecting submicroscopic infections ≥ 0.01 parasites/µL. Thus, although the LAMP assay is more sensitive than microscopy, it missed a significant portion of the submicroscopic reservoir. These findings have important implications for malaria control, particularly in settings where low-density infections predominate.
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Affiliation(s)
- Shereen Katrak
- Department of Medicine, University of California San Francisco, San Francisco, California;,Address correspondence to Shereen Katrak, Department of Medicine, University of California San Francisco, 513 Parnassus Avenue, Room S380, Box 0654, San Francisco, CA 94143. E-mail:
| | - Maxwell Murphy
- Department of Medicine, University of California San Francisco, San Francisco, California
| | | | - John Rek
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Mary Smith
- Chicago Medical School, Rosalind Franklin University, North Chicago, Illinois
| | - Emmanuel Arinaitwe
- Infectious Diseases Research Collaboration, Kampala, Uganda;,London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Joaniter I. Nankabirwa
- Infectious Diseases Research Collaboration, Kampala, Uganda;,School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Moses Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda;,School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, University of California San Francisco, San Francisco, California
| | - Philip J. Rosenthal
- Department of Medicine, University of California San Francisco, San Francisco, California
| | - Bryan Greenhouse
- Department of Medicine, University of California San Francisco, San Francisco, California
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26
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Akerele D, Ljolje D, Talundzic E, Udhayakumar V, Lucchi NW. Molecular diagnosis of Plasmodium ovale by photo-induced electron transfer fluorogenic primers: PET-PCR. PLoS One 2017. [PMID: 28640824 PMCID: PMC5480860 DOI: 10.1371/journal.pone.0179178] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Accurate diagnosis of malaria infections continues to be challenging and elusive, especially in the detection of submicroscopic infections. Developing new malaria diagnostic tools that are sensitive enough to detect low-level infections, user friendly, cost effective and capable of performing large scale diagnosis, remains critical. We have designed novel self-quenching photo-induced electron transfer (PET) fluorogenic primers for the detection of P. ovale by real-time PCR. In our study, a total of 173 clinical samples, consisting of different malaria species, were utilized to test this novel PET-PCR primer. The sensitivity and specificity were calculated using nested-PCR as the reference test. The novel primer set demonstrated a sensitivity of 97.5% and a specificity of 99.2% (95% CI 85.2–99.8% and 95.2–99.9% respectively). Furthermore, the limit of detection for P. ovale was found to be 1 parasite/μl. The PET-PCR assay is a new molecular diagnostic tool with comparable performance to other commonly used PCR methods. It is relatively easy to perform, and amiable to large scale malaria surveillance studies and malaria control and elimination programs. Further field validation of this novel primer will be helpful to ascertain the utility for large scale malaria screening programs.
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Affiliation(s)
- David Akerele
- Division of Pediatric Infectious Diseases, Emory Medical Center, Atlanta, Georgia, United States of America
| | - Dragan Ljolje
- Atlanta Research and Education Foundation, Decatur, Georgia, United States of America
| | - Eldin Talundzic
- Atlanta Research and Education Foundation, Decatur, Georgia, United States of America
| | - Venkatachalam Udhayakumar
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Naomi W. Lucchi
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail:
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27
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Zhao Y, Zhao Y, Lv Y, Liu F, Wang Q, Li P, Zhao Z, Liu Y, Cui L, Fan Q, Cao Y. Comparison of methods for detecting asymptomatic malaria infections in the China-Myanmar border area. Malar J 2017; 16:159. [PMID: 28427455 PMCID: PMC5397696 DOI: 10.1186/s12936-017-1813-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/09/2017] [Indexed: 02/06/2023] Open
Abstract
Background Sensitive methods for detecting asymptomatic malaria infections are essential for identifying potential transmission reservoirs and obtaining an accurate assessment of malaria epidemiology in low-endemicity areas aiming to eliminate malaria. PCR techniques to detect parasite nucleic acids (DNA or RNA) are among the most commonly used molecular methods. However, most of these methods are of low throughput and cannot be used for large-scale molecular epidemiological studies. A recently developed capture and ligation probe-PCR (CLIP-PCR) is claimed to have the sensitivity of molecular techniques and the high throughput capacity needed for screening purposes. This study aimed to compare several molecular methods for detecting asymptomatic and submicroscopic Plasmodium infections in healthy residents of a malaria-hypoendemic region in Southeast Asia, where malaria elimination is in sight. Method This study compared three molecular detection methods side-by-side, namely nested PCR targeting the rRNA genes, nested RT-PCR to detect parasite rRNA, and CLIP-PCR to detect parasite rRNA in 1005 healthy individuals in northeastern Myanmar. For nested PCR and RT-PCR, parasite DNA and total RNA were extracted from ~100 µL of blood, whereas RNA used for CLIP-PCR was from a 3 mm disk of dried blood filter paper. The sensitivity and specificity of these methods were compared with those of conventional light microscopy. In addition, RT-PCR and quantitative RT-PCR (qRT-PCR) targeting the Pvs25 gene in Plasmodium vivax were used to assess gametocyte prevalence in the samples. Results Light microscopy detected Plasmodium infections in only 1.19% of the residents harbouring the parasites. CLIP-PCR had slightly better performance and detected Plasmodium infections in 1.89% of the population. Further improvement was achieved by nested PCR to detect parasite DNA, which detected P. vivax and Plasmodium falciparum infections in 2.39% of the residents. The nested RT-PCR targeting rRNA, however, detected as many as 187 (18.61%) individuals having Plasmodium infections with P. vivax being the predominant species (176 P. vivax, 5 P. falciparum and 6 P. falciparum/P. vivax mixed infections). Of the 210 Plasmodium-positive samples detected by all molecular methods, 115 were Pvs25-positive by qRT-PCR, indicating that a large proportion of asymptomatic individuals were gametocyte carriers. Conclusion Nested RT-PCR based on the detection of asexual-stage parasite rRNA was the most sensitive, with a more than sixfold higher sensitivity than the other two molecular methods of parasite detection. CLIP-PCR has an increased throughput, but its sensitivity in this study was much lower than those of other molecular methods, which may be partially due to the smaller amount of RNA input used. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1813-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yonghong Zhao
- Department of Immunology, China Medical University, Shenyang, Liaoning, China
| | - Yan Zhao
- Department of Immunology, China Medical University, Shenyang, Liaoning, China
| | - Yanmin Lv
- Department of Immunology, China Medical University, Shenyang, Liaoning, China
| | - Fei Liu
- Department of Immunology, China Medical University, Shenyang, Liaoning, China
| | - Qinghui Wang
- Department of Immunology, China Medical University, Shenyang, Liaoning, China
| | - Peipei Li
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Zhenjun Zhao
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Yingjie Liu
- Department of Pathogen Biology, China Medical University, Shenyang, Liaoning, China
| | - Liwang Cui
- Department of Entomology, Pennsylvania State University, University Park, PA, USA.
| | - Qi Fan
- Dalian Institute of Biotechnology, Dalian, Liaoning, China.
| | - Yaming Cao
- Department of Immunology, China Medical University, Shenyang, Liaoning, China.
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Daniels RF, Deme AB, Gomis JF, Dieye B, Durfee K, Thwing JI, Fall FB, Ba M, Ndiop M, Badiane AS, Ndiaye YD, Wirth DF, Volkman SK, Ndiaye D. Evidence of non-Plasmodium falciparum malaria infection in Kédougou, Sénégal. Malar J 2017; 16:9. [PMID: 28049489 PMCID: PMC5209815 DOI: 10.1186/s12936-016-1661-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 12/16/2016] [Indexed: 11/10/2022] Open
Abstract
Background Expanded malaria control efforts in Sénégal have resulted in increased use of rapid diagnostic tests (RDT) to identify the primary disease-causing Plasmodium species, Plasmodium falciparum. However, the type of RDT utilized in Sénégal does not detect other malaria-causing species such as Plasmodium ovale spp., Plasmodium malariae, or Plasmodium vivax. Consequently, there is a lack of information about the frequency and types of malaria infections occurring in Sénégal. This study set out to better determine whether species other than P. falciparum were evident among patients evaluated for possible malaria infection in Kédougou, Sénégal. Methods Real-time polymerase chain reaction speciation assays for P. vivax, P. ovale spp., and P. malariae were developed and validated by sequencing and DNA extracted from 475 Plasmodium falciparum-specific HRP2-based RDT collected between 2013 and 2014 from a facility-based sample of symptomatic patients from two health clinics in Kédougou, a hyper-endemic region in southeastern Sénégal, were analysed. Results Plasmodium malariae (n = 3) and P. ovale wallikeri (n = 2) were observed as co-infections with P. falciparum among patients with positive RDT results (n = 187), including one patient positive for all three species. Among 288 negative RDT samples, samples positive for P. falciparum (n = 24), P. ovale curtisi (n = 3), P. ovale wallikeri (n = 1), and P. malariae (n = 3) were identified, corresponding to a non-falciparum positivity rate of 2.5%. Conclusions These findings emphasize the limitations of the RDT used for malaria diagnosis and demonstrate that non-P. falciparum malaria infections occur in Sénégal. Current RDT used for routine clinical diagnosis do not necessarily provide an accurate reflection of malaria transmission in Kédougou, Sénégal, and more sensitive and specific methods are required for diagnosis and patient care, as well as surveillance and elimination activities. These findings have implications for other malaria endemic settings where species besides P. falciparum may be transmitted and overlooked by control or elimination activities. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1661-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rachel F Daniels
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA. .,Infectious Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
| | - Awa Bineta Deme
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal
| | - Jules F Gomis
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology and Mycology, Cheikh Anta Diop University/Le Dantec Hospital, Dakar, Senegal.,Malaria Branch, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Baba Dieye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal
| | - Katelyn Durfee
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Julie I Thwing
- Malaria Branch, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.,President's Malaria Initiative, Dakar, Senegal
| | - Fatou B Fall
- National Malaria Control Programme, Dakar, Senegal
| | - Mady Ba
- National Malaria Control Programme, Dakar, Senegal
| | | | - Aida S Badiane
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology and Mycology, Cheikh Anta Diop University/Le Dantec Hospital, Dakar, Senegal.,Malaria Branch, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | | - Dyann F Wirth
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Infectious Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Sarah K Volkman
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, MA, USA. .,Infectious Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA, USA. .,School of Nursing and Health Sciences, Simmons College, Boston, MA, USA.
| | - Daouda Ndiaye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Dakar, Senegal.,Laboratory of Parasitology and Mycology, Cheikh Anta Diop University/Le Dantec Hospital, Dakar, Senegal.,Malaria Branch, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
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