scholarly journals High prevalence of Plasmodium malariae and Plasmodium ovale in co-infections with Plasmodium falciparum in asymptomatic malaria parasite carriers in Southwest Nigeria

2021 ◽  
Author(s):  
Muhydeen Abiodun Abdulraheem ◽  
Medard Ernest ◽  
Ifeoma Ugwuanyi ◽  
Hussein M. Abkallo ◽  
Saori Nishikawa ◽  
...  
Keyword(s):  
Species Composition ◽  
Malaria Parasite ◽  
Dna Analysis ◽  
Plasmodium Malariae ◽  
Asymptomatic Malaria ◽  
Plasmodium Ovale ◽  
Sample Collection ◽  
Southwest Nigeria ◽  
Asymptomatic Infections ◽  
Pcr Targeting

AbstractAsymptomatic malaria parasite carriers do not seek anti-malarial treatment and may constitute a silent infectious reservoir. In order to assess the level of asymptomatic and symptomatic carriage amongst adolescents in a highly endemic area, and to identify the risk factors associated with such carriage, we conducted a cross sectional survey of 1032 adolescents (ages 10-19) from eight schools located in Ibadan, Southwest Nigeria in 2016. Blood films and blood spot filter paper samples were prepared for microscopy and DNA analysis. The prevalence of asymptomatic malaria was determined using microscopy, rapid diagnostic tests and PCR for 658 randomly selected samples. Of these, we found that 80% of asymptomatic schoolchildren were positive for malaria parasites by PCR, compared to 47% and 9% determined by RDT and microscopy, respectively. Malaria parasite species typing was performed using PCR targeting the mitochondrial CoxIII gene, and revealed high rates of carriage of Plasmodium malariae (53%) and Plasmodium ovale (24%). Most asymptomatic infections were co-infections of two or more species (62%), with P. falciparum + P. malariae the most common (35%), followed by P. falciparum + P. malariae + P. ovale (21%) and P. falciparum + P. ovale (6%). Single infections of P. falciparum, P. malariae and P. ovale accounted for 24%, 10% and 4% of all asymptomatic infections respectively. To compare the species composition of asymptomatic and symptomatic infections, further sample collection was carried out in 2017 at one of the previously sampled schools, and at a nearby hospital. Whilst the species composition of the asymptomatic infections was similar to that observed in 2016, the symptomatic infections were markedly different, with single infections of P. falciparum observed in 91% of patients, P. falciparum + P. malariae in 5% and P. falciparum + P. ovale in 4%.

scholarly journals Large Variations in Malaria Parasite Carriage by Afebrile School Children Living in Nearby Communities in the Central Region of Ghana

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Evans K. Obboh ◽  
Ruth E. Okonu ◽  
Linda E. Amoah
Keyword(s):  
Malaria Transmission ◽  
Central Region ◽  
Malaria Control ◽  
Filter Paper ◽  
Malaria Parasite ◽  
Molecular Evidence ◽  
Asymptomatic Malaria ◽  
Cape Coast ◽  
Malaria Parasites ◽  
Asymptomatic Infections

Background. Indicators of successful malaria control interventions include a reduction in the prevalence and densities of malaria parasites contained in both symptomatic and asymptomatic infections as well as a reduction in malaria transmission. Individuals harboring malaria parasites in asymptomatic infections serve as reservoirs for malaria transmission. This study determined the prevalence of asymptomatic malaria parasite carriage in afebrile children attending six different schools in two districts, the Cape Coast Metropolitan Assembly (CCMA) and the Komenda Edina Eguafo Abirem (KEEA) of the Central Region of Ghana. Methods. This cross sectional study recruited afebrile children aged between 3 and 15 years old from six randomly selected schools in the Central Region of Ghana. Finger-pricked blood was collected and used to prepare thick and thin blood smears as well as spot a strip of filter paper (Whatman #3). Nested PCR was used to identify Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale, and Plasmodium vivax in DNA extracted from the filter paper spots. The multiplicity of P. falciparum infection was determined using merozoite surface protein 2 genotyping. Results. Out of the 528 children sampled, PCR identified 27.1% to harbor Plasmodium parasites in asymptomatic infections, whilst microscopy identified malaria parasites in 10.6% of the children. The overall PCR estimated prevalence of P. falciparum and P. malariae was 26.6% and 1.3%, respectively, with no P. ovale or P. vivax identified by PCR or microscopy. The RDT positivity rate ranged from 55.8% in Simiw to 4.5% in Kuful. Children from the Simiw Basic School accounted for 87.5% of all the asymptomatic infections. The multiplicity of P. falciparum infection was predominantly monoclonal and biclonal. Conclusions. The low prevalence of asymptomatic malaria parasite carriage by the children living in the Cape Coast Metropolis suggests that the malaria control interventions in place in CCMA are highly effective and that additional malaria control interventions are required for the KEEA district to reduce the prevalence of asymptomatic malaria parasite carriers. No molecular evidence of P. ovale and P. vivax was identified in the afebrile children sampled from the selected schools.

scholarly journals Diagnosis of imported malaria in Japan by using microtiter plate-hybridization technique

2015 ◽  
Vol 41 (2) ◽  
pp. 241-246
Author(s):  
Tangin Akter
Keyword(s):  
Plasmodium Falciparum ◽  
Malaria Parasite ◽  
Plasmodium Malariae ◽  
Microtiter Plate ◽  
Imported Malaria ◽  
Hybridization Technique ◽  
Plasmodium Ovale ◽  
Blood Samples ◽  
Great Problem ◽  
Microscopic Diagnosis

In Japan, malaria has been successfully eradicated but imported malaria is still a great problem. Blood samples of malaria patients were collected from different hospitals of Japan. The samples were diagnosed by PCR based Microtiter plate-hybridization technique (MPH). The results of MPH were compared with microscopic diagnosis done at the laboratories of different hospitals. Among the total 23 blood samples examined, 19 were diagnosed as malaria parasite positive by MPH technique. The malaria parasites found were Plasmodium falciparum 7 (36.7%), Plasmodium vivax 6 (31.6%), Plasmodium ovale 1 (5.3%), Plasmodium ovale variant 3 (15.8%), Plasmodium malariae 1 (5.3%). One mixed infection of P. falciparum and P. ovale (5.3%) were also recorded. The area of acquisition of malaria was highest from Africa followed by Oceania, Asia, South America and others. This investigation indicated the MPH technique was more specific than microscopy for the diagnosis of imported malaria.Bangladesh J. Zool. 41(2): 241-246, 2013

scholarly journals High prevalence of asymptomatic malaria infections in adults, Ashanti Region, Ghana, 2018

2020 ◽  
Author(s):  
Melina Heinemann ◽  
Richard O. Phillips ◽  
Christof D. Vinnemeier ◽  
Christina Rolling ◽  
Egbert Tannich ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Plasmodium Malariae ◽  
Asymptomatic Malaria ◽  
Plasmodium Ovale ◽  
Forest Zone ◽  
Ashanti Region ◽  
Plasmodium Ovale Curtisi ◽  
High Prevalence ◽  
Asymptomatic Adult ◽  
Species Specific

Abstract Background Ghana is among the high-burden countries for malaria infection and recently reported a notably increase in malaria cases. While asymptomatic parasitemia is increasingly recognized as a hurdle for malaria elimination, studies on asymptomatic malaria are scarce and usually focus on children and on non-falciparum species. The present study aims to assess the prevalence of asymptomatic Plasmodium falciparum and non-falciparum infections in Ghanaian adults in the Ashanti region during the high transmission season. Methods Asymptomatic adult residents from five villages in the Ashanti Region, Ghana, were screened for Plasmodium spp. by rapid diagnostic test (RDT) and polymerase chain reaction (PCR) during the rainy season. Samples tested positive were subtyped using species-specific real-time PCR. For all P. ovale infections additional sub-species identification was performed.Results Molecular prevalence of asymptomatic Plasmodium infection was 284/391 (73%); only 126 (32%) infections were detected by RDT. While 266 (68%) participants were infected with Plasmodium falciparum, 33 (8%) were infected with Plasmodium malariae and 34 (9%) with Plasmodium ovale. The sub-species Plasmodium ovale curtisi and P. ovale wallikeri were identified to similar proportions. Non-falciparum infections usually presented as mixed infections with Plasmodium falciparum.Conclusions Most adult residents in the Ghanaian forest zone are asymptomatic Plasmodium carriers. The high Plasmodium prevalence not detected by RDT in adults highlights that malaria eradication efforts must target all members of the population. Beneath Plasmodium falciparum, screening and treatment must also include infections with Plasmodium malariae, P. ovale curtisi and P. ovale wallikeri .

scholarly journals Genotyping cognate Plasmodium falciparum in humans and mosquitoes to estimate onward transmission of asymptomatic infections

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kelsey M. Sumner ◽  
Elizabeth Freedman ◽  
Lucy Abel ◽  
Andrew Obala ◽  
Brian W. Pence ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Odds Ratio ◽  
Asymptomatic Malaria ◽  
Major Contributor ◽  
Western Kenya ◽  
High Transmission ◽  
Transmission Reduction ◽  
Asymptomatic Infections ◽  
Infection Types ◽  
Natural Settings

AbstractMalaria control may be enhanced by targeting reservoirs of Plasmodium falciparum transmission. One putative reservoir is asymptomatic malaria infections and the scale of their contribution to transmission in natural settings is not known. We assess the contribution of asymptomatic malaria to onward transmission using a 14-month longitudinal cohort of 239 participants in a high transmission site in Western Kenya. We identify P. falciparum in asymptomatically- and symptomatically-infected participants and naturally-fed mosquitoes from their households, genotype all parasites using deep sequencing of the parasite genes pfama1 and pfcsp, and use haplotypes to infer participant-to-mosquito transmission through a probabilistic model. In 1,242 infections (1,039 in people and 203 in mosquitoes), we observe 229 (pfcsp) and 348 (pfama1) unique parasite haplotypes. Using these to link human and mosquito infections, compared with symptomatic infections, asymptomatic infections more than double the odds of transmission to a mosquito among people with both infection types (Odds Ratio: 2.56; 95% Confidence Interval (CI): 1.36–4.81) and among all participants (OR 2.66; 95% CI: 2.05–3.47). Overall, 94.6% (95% CI: 93.1–95.8%) of mosquito infections likely resulted from asymptomatic infections. In high transmission areas, asymptomatic infections are the major contributor to mosquito infections and may be targeted as a component of transmission reduction.

scholarly journals The ears of the African elephant: unexpected high seroprevalence of Plasmodium ovale and Plasmodium malariae in healthy populations in Western Africa

2014 ◽  
Vol 13 (1) ◽  
Author(s):  
Cécile Doderer-Lang ◽  
Pascal S Atchade ◽  
Lydia Meckert ◽  
Elodie Haar ◽  
Sylvie Perrotey ◽  
...  
Keyword(s):  
Plasmodium Malariae ◽  
African Elephant ◽  
Plasmodium Ovale ◽  
High Seroprevalence ◽  
Western Africa

scholarly journals Development of Cooperative Primer-Based Real-Time PCR Assays for the Detection of Plasmodium malariae and Plasmodium ovale

2021 ◽  
Vol 23 (10) ◽  
pp. 1393-1403
Author(s):  
Felix Ansah ◽  
Jonathan Suurbaar ◽  
Derrick Darko ◽  
Nsoh G. Anabire ◽  
Samuel O. Blankson ◽  
...  
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Plasmodium Malariae ◽  
Plasmodium Ovale ◽  
Pcr Assays

scholarly journals Contribution of Asymptomatic Plasmodium Infections to the Transmission of Malaria in Kayin State, Myanmar

2018 ◽  
Vol 219 (9) ◽  
pp. 1499-1509 ◽  
Author(s):  
Victor Chaumeau ◽  
Ladda Kajeechiwa ◽  
Bénédicte Fustec ◽  
Jordi Landier ◽  
Saw Naw Nyo ◽  
...  
Keyword(s):  
Malaria Transmission ◽  
Entomological Inoculation Rate ◽  
Fold Increase ◽  
Estimating Equation ◽  
Malaria Prevalence ◽  
Pcr Analysis ◽  
Asymptomatic Malaria ◽  
Asymptomatic Infections ◽  
Greater Mekong Subregion ◽  
The Impact

Abstract Background The objective of mass antimalarial drug administration (MDA) is to eliminate malaria rapidly by eliminating the asymptomatic malaria parasite reservoirs and interrupting transmission. In the Greater Mekong Subregion, where artemisinin-resistant Plasmodium falciparum is now widespread, MDA has been proposed as an elimination accelerator, but the contribution of asymptomatic infections to malaria transmission has been questioned. The impact of MDA on entomological indices has not been characterized previously. Methods MDA was conducted in 4 villages in Kayin State (Myanmar). Malaria mosquito vectors were captured 3 months before, during, and 3 months after MDA, and their Plasmodium infections were detected by polymerase chain reaction (PCR) analysis. The relationship between the entomological inoculation rate, the malaria prevalence in humans determined by ultrasensitive PCR, and MDA was characterized by generalized estimating equation regression. Results Asymptomatic P. falciparum and Plasmodium vivax infections were cleared by MDA. The P. vivax entomological inoculation rate was reduced by 12.5-fold (95% confidence interval [CI], 1.6–100-fold), but the reservoir of asymptomatic P. vivax infections was reconstituted within 3 months, presumably because of relapses. This was coincident with a 5.3-fold (95% CI, 4.8–6.0-fold) increase in the vector infection rate. Conclusion Asymptomatic infections are a major source of malaria transmission in Southeast Asia.

Asymptomatic Malaria Infection and Their Antibodies Against Malaria: A Study in Abra de Ilog, Occidental Mindoro, Philippines

2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S116-S116
Author(s):  
Carlo Ledesma ◽  
Ma Gina Sadang
Keyword(s):  
Real Time ◽  
Malaria Infection ◽  
Malaria Parasite ◽  
National Commission ◽  
Enzyme Linked Immunosorbent Assay ◽  
Asymptomatic Malaria ◽  
Blood Samples ◽  
Blood Smears ◽  
Specific Igg

Abstract Human malaria, caused by four species of Plasmodium, namely P falciparum, P vivax, P malariae, and P ovale, remains a health problem of global concern, with one to two million deaths annually and risking about two billion people worldwide. Alternative ways of controlling the incidence of malaria through understanding the host’s immune response to monoinfection and the detection of the presence of asymptomatic malaria infection are the factors being addressed in this study. The determination of the possible existence of cross-antigenic stimulation is a matter of great significance for future research and development. The isolation of these antigenic structures may give the first step to the development of better vaccines that may protect the general population who are at risk of developing malaria. Prior to blood collection, a memorandum of agreement was signed between the researcher and the Iraya-Mangyan leaders of Abra de Ilog, Occidental Mindoro. A Certificate Precondition was issued by the National Commission of Indigenous Peoples, which was required by the Graduate School Ethics Review Committee. Determination of the presence of malaria parasite on blood samples of residents of two barangays in Abra de Ilog, Occidental Mindoro, was performed using two methods: microscopic examination of stained blood smears for the presence of malaria parasite and polymerase chain reaction. Blood smears were prepared and eventually stained using Giemsa and Dip Quick stains. The detection of 5 positive cases of malaria infection with ring/schizont stage among the 53 cases was a clear indication of positive asymptomatic cases. Nested PCR using Plasmodium spp.–specific primer as well as P falciparum–specific and P vivax–specific primers showed the absence of bands so that one of the recommendations in this study is the performance of real-time PRC using more sensitive primers. Levels of P falciparum and P vivax–specific immunoglobulin were measured using an enzyme-linked immunosorbent assay revealing a higher level of PF-specific IgG than PV-specific IgG. Whole blood samples were saved for future determinations such as real-time PCR, immunophenotypic analysis, and possible parasitic culture. Further similar studies may also be done by increasing the number of respondents as well as the areas of concern for a more extensive scope.

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