High prevalence of plasmodium malariae and plasmodium ovale in co-infections with plasmodium falciparum in asymptomatic malaria parasite carriers in southwestern nigeria

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 .

Download Full-text

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

Bangladesh Journal of Zoology ◽

10.3329/bjz.v41i2.23327 ◽

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

Download Full-text

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

Malaria Journal ◽

10.1186/s12936-020-03441-z ◽

2020 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Melina Heinemann ◽

Richard O. Phillips ◽

Christof D. Vinnemeier ◽

Christina C. Rolling ◽

Egbert Tannich ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Plasmodium Malariae ◽

Asymptomatic Malaria ◽

Forest Zone ◽

Transmission Season ◽

Ashanti Region ◽

High Prevalence ◽

Notable Increase ◽

Asymptomatic Adult ◽

Species Specific

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

Download Full-text

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

10.1101/2021.01.14.21249635 ◽

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%.

Download Full-text

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

10.21203/rs.3.rs-21341/v2 ◽

2020 ◽

Author(s):

Melina Heinemann ◽

Richard O. Phillips ◽

Christof D. Vinnemeier ◽

Christina Rolling ◽

Egbert Tannich ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Plasmodium Species ◽

Plasmodium Malariae ◽

Asymptomatic Malaria ◽

Forest Zone ◽

Transmission Season ◽

Ashanti Region ◽

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

Download Full-text

Persistent transmission of Plasmodium malariae and Plasmodium ovale species in an area of declining Plasmodium falciparum transmission in eastern Tanzania

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0007414 ◽

2019 ◽

Vol 13 (5) ◽

pp. e0007414 ◽

Cited By ~ 14

Author(s):

Victor Yman ◽

Grace Wandell ◽

Doreen D. Mutemi ◽

Aurelie Miglar ◽

Muhammad Asghar ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Plasmodium Malariae ◽

Plasmodium Ovale

Download Full-text

Plasmodium falciparum DHFR and DHPS Mutations Are Associated With HIV-1 Co-Infection and a Novel DHPS Mutation I504T Is Identified in Western Kenya

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2020.600112 ◽

2020 ◽

Vol 10 ◽

Author(s):

Brandi K. Torrevillas ◽

Sarah M. Garrison ◽

Alexander J. McKeeken ◽

Dharmeshkumar Patel ◽

James T. Van Leuven ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Haplotype Diversity ◽

Plasmodium Malariae ◽

Drug Binding ◽

Cross Resistance ◽

Asymptomatic Malaria ◽

Newly Diagnosed ◽

Cross Sectional ◽

Antifolate Resistance ◽

Hiv 1

Antifolate resistance is significant in Kenya and presumed to result from extensive use and cross-resistance between antifolate antimalarials and antibiotics, including cotrimoxazole/Bactrim used for HIV-1 chemotherapy. However, little is known about antifolate-resistant malaria in the context of newly diagnosed HIV-1 co-infection prior to administration of HIV-1 chemotherapy. Blood samples from a cross-sectional study of asymptomatic adult Kenyans enrolled during voluntary HIV testing were analyzed by PCR for Plasmodium spp. More than 95% of volunteers with identifiable parasite species (132 HIV-1 co-infected) were infected with Plasmodium falciparum alone or P. falciparum with Plasmodium ovale and/or Plasmodium malariae. Deep sequencing was used to screen for mutations in P. falciparum dihydrofolate reductase (dhfr) (N51I, C59R, S108N, I164L) and dihydropteroate synthase (dhps) (S436H, A437G, K540E, A581G) from 1133 volunteers. Individual mutations in DHPS but not DHFR correlated with HIV-1 status. DHFR haplotype diversity was significantly different among volunteers by gender and HIV-1 status. DHPS haplotype diversity by HIV-1 status was significantly different between volunteers paired by age and gender, indicating that patterns of resistance were independent of these variables. Molecular simulations for a novel DHPS mutation (I504T) suggested that the mutated protein has increased affinity for the endogenous ligand DHPPP and decreased affinity for drug binding. A sub-group of monoclonal infections revealed that age and parasitemia were not correlated and enabled identification of a rare septuple-mutant haplotype (IRNL-HGEA). In our study, adult Kenyans newly diagnosed with HIV-1 infection were predominantly infected with moderately resistant P. falciparum, with patterns of infecting parasite genotypes significantly associated with HIV-1 status. Together with the discovery of DHPS I504T, these data indicate that antifolate resistance continues to evolve in Kenya. Further, they highlight the need to understand the effects of associated mutations on both fitness and resistance of P. falciparum in the context of HIV-1 co-infection to better inform treatment for asymptomatic malaria.

Download Full-text

Molecular Analysis of Erythrocyte Invasion in Plasmodium falciparum Isolates from Senegal

Infection and Immunity ◽

10.1128/iai.00122-07 ◽

2007 ◽

Vol 75 (7) ◽

pp. 3531-3538 ◽

Cited By ~ 37

Author(s):

Cameron V. Jennings ◽

Ambroise D. Ahouidi ◽

Martine Zilversmit ◽

Amy K. Bei ◽

Julian Rayner ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Gene Amplification ◽

Malaria Parasite ◽

Sequence Polymorphism ◽

Invasion Pathways ◽

Specific Sequence ◽

Erythrocyte Invasion ◽

Sequence Deletion ◽

High Prevalence ◽

Transmission Area

ABSTRACT The human malaria parasite, Plasmodium falciparum, utilizes multiple ligand-receptor interactions for the invasion of human erythrocytes. Members of the reticulocyte binding protein homolog (PfRh) family have been shown to be critical for directing parasites to alternative erythrocyte receptors that define invasion pathways. Recent studies have identified gene amplification, sequence polymorphism, and variant expression of PfRh paralogs as mechanisms underlying discrimination between pathways for invasion. In this study, we find considerable heterogeneity in the invasion profiles of clonal, uncultured P. falciparum parasite isolates from a low-transmission area in Senegal. Molecular analyses revealed minimal variation in protein expression levels of the PfRh ligands, PfRh1, PfRh2a, and PfRh2b, and an absence of gene amplification in these isolates. However, significant sequence polymorphism was found within repeat regions of PfRh1, PfRh2a, and PfRh2b. Furthermore, we identified a large sequence deletion (∼0.58 kb) in the C-terminal region of the PfRh2b gene at a high prevalence in this population. In contrast to findings of earlier studies, we found no associations between specific sequence variants and distinct invasion pathways. Overall these data highlight the importance of region-specific elaborations in PfRh sequence and expression polymorphisms, which has important implications in our understanding of how the malaria parasite responds to polymorphisms in erythrocyte receptors and/or evades the immune system.

Download Full-text

Molecular Epidemiology of Plasmodium falciparum Chloroquine Resistance Transporter Genes among School Children in Kwara State, Southwestern Nigeria

International Journal of TROPICAL DISEASE & Health ◽

10.9734/ijtdh/2020/v41i230249 ◽

2020 ◽

pp. 1-12

Author(s):

A. O. Oluwasogo ◽

H. O. Ismail ◽

D. A. Pelumi

Keyword(s):

Plasmodium Falciparum ◽

Malaria Parasite ◽

Chloroquine Resistance ◽

Fixation Method ◽

Age Group ◽

Wild Type ◽

School Students ◽

Southwestern Nigeria ◽

Parasite Count ◽

Chloroquine Resistance Transporter

Background: Plasmodium falciparum existence continues to develop resistance to conventional antimalaria drugs in malaria endemic areas. Plasmodia often prevent drugs from interacting with the target site, hence, developing resistance to antimalaria drugs. Mutations in the Plasmodium falciparum chloroquine resistance transporter (Pfcrt), are the major determinant of chloroquine resistance in human malaria parasite. Methodology: Malaria infection, Pfcrt and Pfmdr1 genes of isolates among school students within the age range of 11-22 years from four selected rural communities of Kwara state were studied. One hundred and eighty seven subjects (187) were selected for the study. Blood samples were collected by finger prick method for malaria screening. Nested PCR and restriction fragment length polymorphism (RFLP) were done to detect alleles of pfcrt at codon 76 and pfmdr1 at codon 86. DNA of isolates was appropriately extracted from the filter paper blots using the methanol fixation method. Logistic regression was performed on the binary observations obtained while linear regression was conducted on the fifty (50) subjects that tested positive to malaria. Results: Out of 187 subjects screened, 26.7% (50) were positive to P. falciparum. Highest malaria parasite count of 36.4% was recorded in 14-16 years age group while 20-22 years age group had the least malaria parasite count (15.4%). The result of the studied isolates indicated that out of 50 isolates analyzed for Pfcrt gene, wild type alleles accounted for 32% (16) while mutant alleles accounted for 68% (34). Alakuko Community accounted for the least number of T76 mutant alleles 10% (5) while Apado community recorded the highest number of T76 mutant gene 22% (11). For Pfmdr1 gene analysis at codon 86, isolates from Apado community showed the highest mutant type alleles (Y86) of 22% (11), while Igbonla community in Ifelodun local government had the least mutant alleles, 6% (3). Conclusion: The overall result revealed existence of mutant alleles in both the Pfcrt and Pfmdr1 genes which was higher than the wild type gene in both cases. The presence of chloroquine resistance genes among the studied population implies that alternative antimalaria drugs should be designed by pharmaceutical industry.

Download Full-text

High cases of submicroscopic Plasmodium falciparum infections in a suburban population of Lagos, Nigeria

Malaria Journal ◽

10.1186/s12936-019-3073-7 ◽

2019 ◽

Vol 18 (1) ◽

Cited By ~ 1

Author(s):

Florence A. Umunnakwe ◽

Emmanuel T. Idowu ◽

Olusola Ajibaye ◽

Blessed Etoketim ◽

Samuel Akindele ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Large Scale ◽

Quantitative Polymerase Chain Reaction ◽

Age Groups ◽

Malaria Diagnosis ◽

School Age Children ◽

Asymptomatic Malaria ◽

High Prevalence ◽

Study Population ◽

Low Sensitivity

Abstract Background Asymptomatic malaria parasites are significant sources of infections for onward malaria transmission. Conventional tools for malaria diagnosis such as microscopy and rapid diagnostic test kits (RDT) have relatively low sensitivity, hence the need for alternative tools for active screening of such low-density infections. Methods This study tested var acidic terminal sequence-based (varATS) quantitative polymerase chain reaction (qPCR) for screening asymptomatic Plasmodium falciparum infections among dwellers of a sub-urban community in Lagos, Nigeria. Clinically healthy participants were screened for malaria using microscopy, RDT and varATS qPCR techniques. Participants were stratified into three age groups: 1–5, 6–14 and > 14 years old. Results Of the 316 participants screened for asymptomatic malaria infection, 78 (24.68%) were positive by microscopy, 99 (31.33%) were positive by RDT and 112 (35.44%) by varATS qPCR. Participants aged 6–14 years had the highest prevalence of asymptomatic malaria, with geometric means of ~ 116 parasites/µL and ~ 6689 parasites/µL as detected by microscopy and varATS, respectively. Conclusion This study has revealed high prevalence of asymptomatic malaria in the study population, with varATS detecting additional sub-microscopic infections. The highest concentration of asymptomatic malaria was observed among school-age children between 6 and 14 years old. A large-scale screening to identify other potential hotspots of asymptomatic parasites in the country is recommended.

Download Full-text