Low prevalence of Plasmodium falciparum parasites lacking pfhrp2/3 genes among asymptomatic and symptomatic school-age children in Kinshasa, Democratic Republic of Congo

Abstract Background. Loss of efficacy of malaria diagnostic tests may lead to untreated or mistreated cases, compromising case management and control. There is an increasing reliance on rapid diagnostic tests (RDTs), with the most widely used of these targeting the Plasmodium falciparum histidine-rich protein 2 gene. There are numerous reports of the deletion of this gene in P. falciparum parasites in some populations, rendering them undetectable by PfHRP2 RDTs. We aimed to identify P. falciparum parasites lacking the P. falciparum histidine rich protein 2 and 3 genes isolated from asymptomatic and symptomatic school-age children in Kinshasa, Democratic Republic of Congo. Methods. We assessed the performance of PfHRP2-based RDTs in comparison to microscopy and PCR. PCR was then used to identify parasite isolates lacking pfhrp2/3 genes. Results. Of 462 DNA samples analysed, deletions of the pfhrp2 and pfhrp3 genes were found in only three (2%) samples and one (1%) sample in the RDT positive subgroup, respectively. No parasites lacking the pfhrp2/3 genes were found in the RDT negative subgroup. Conclusion. Plasmodium falciparum histidine-rich protein 2/3 gene deletions are uncommon in the surveyed population, and do not result in diagnostic failure. We encourage the use of rigorous PCR methods to identify pfhrp2/3 gene deletions in order to minimize the overestimation of their prevalence.

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Prevalence of Plasmodium falciparum isolates lacking the histidine rich protein 2 gene among symptomatic malaria patients in Kwilu Province of the Democratic Republic of Congo

Infectious Diseases of Poverty ◽

10.1186/s40249-021-00860-1 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Yannick Bazitama Munyeku ◽

Alain Abera Musaka ◽

Medard Ernest ◽

Chris Smith ◽

Paul Mankadi Mansiangi ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Diagnostic Tests ◽

Gene Deletion ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

False Negative ◽

Rapid Diagnostic Tests ◽

Republic Of Congo ◽

Gene Deletions ◽

Symptomatic Malaria

Abstract Background Malaria rapid diagnostic tests have become a primary and critical tool for malaria diagnosis in malaria-endemic countries where Plasmodium falciparum Histidine Rich Protein 2-based rapid diagnostic tests (PfHRP2-based RDTs) are widely used. However, in the last decade, the accuracy of PfHRP2-based RDTs has been challenged by the emergence of P. falciparum strains harbouring deletions of the P. falciparum histidine rich protein 2 (pfhrp2) gene, resulting in false-negative results. In the Democratic Republic of Congo (D.R. Congo), little is known about the prevalence of the pfhrp2 gene deletion among P. falciparum isolates infecting symptomatic patients, especially in low to moderate transmission areas where pfhrp2 deletion parasites are assumed to emerge and spread. Here we determine the local prevalence and factors associated with pfhrp2 gene deletions among symptomatic malaria patients in the Kwilu Province of the D.R. Congo. Methods We used secondary data from a prospective health facility-based cross-sectional study conducted in 2018. Blood was collected for microscopy, PfHRP2-RDT, and spotted onto Whatman filter paper for downstream genetic analysis. Genomic DNA was extracted and used to perform PCR assays for the detection and confirmation of pfhrp2 gene deletions. Fischer’s exact and the Kruskal–Wallis tests were applied to look for associations between potential explanatory variables and the pfhrp2 gene deletion with a level of statistical significance set at P < 0.05. Results Of the 684 enrolled symptomatic patients, 391 (57.7%) were female. The majority (87.7%) reported the presence of mosquito breeding sites within the household’s compound, and fever was the most reported symptom (81.6%). The overall prevalence of the pfhrp2 gene deletion was 9.2% (95% CI: 6.7%–12.1%). The deletion of the pfhrp2 gene was associated with health zone of origin (P = 0.012) and age (P = 0.019). Among false-negative PfHRP2-RDT results, only 9.9% were due to pfhrp2 gene deletion. Conclusions P. falciparum isolates with pfhrp2 gene deletions are relatively common among symptomatic patients in Kwilu province. Further investigations are needed to provide enough evidence for policy change. Meanwhile, the use of RDTs targeting PfHRP2 and parasite lactate dehydrogenase (pLDH) antigens could limit the spread of deleted isolates. Graphic Abstract

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Identification of polymorphisms in genes associated with drug resistance in Plasmodium falciparum isolates from school-age children in Kinshasa, Democratic Republic of Congo

Parasitology International ◽

10.1016/j.parint.2022.102541 ◽

2022 ◽

pp. 102541

Author(s):

Sabin S. Nundu ◽

Richard Culleton ◽

Shirley V. Simpson ◽

Hiroaki Arima ◽

Ben-Yeddy Abel Chitama ◽

...

Keyword(s):

Drug Resistance ◽

Plasmodium Falciparum ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

School Age Children ◽

School Age ◽

Republic Of Congo

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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

10.21203/rs.3.rs-389568/v1 ◽

2021 ◽

Author(s):

Sabin S. Nundu ◽

Richard Culleton ◽

Shirley V. Simpson ◽

Hiroaki Arima ◽

Jean-Jacques Muyembe ◽

...

Keyword(s):

Urban Area ◽

Rural Area ◽

Malaria Parasite ◽

Parasite Species ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

School Age Children ◽

Asymptomatic Malaria ◽

School Age ◽

Republic Of Congo

Abstract Background. Malaria remains a major public health concern in 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. 634 (427 asymptomatic and 207 symptomatic) blood samples were collected from a cross-sectional survey of school-age children aged 6 to 14 years both without and with malaria symptoms. Nested-PCR was performed for malaria parasite species typing. Results. The overall prevalence of Plasmodium spp., Plasmodium falciparum, Plasmodium malariae and Plasmodium ovale was 62.3, 58.1, 19.9 and 10.8% among asymptomatic whereas it was 94.4, 93.2, 12.6 and 15.9% in symptomatic children, 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% of children in the rural area were co-infected with two or more species with P. falciparum + P. malariae the most common (24%) whereas in the urban setting, fewer children carried co-infections (16%) with P. falciparum + P. malariae again the most common (9%). A fifth of rural-dwelling symptomatic children were co-infected with two or more species with P. falciparum + P. ovale the most common (14%), while a quarter of symptomatic children in the urban area carried multiple species, with co-infections of P. falciparum + P. malariae the most common (11%). Conclusion. School-age children are at significant risk from both asymptomatic and symptomatic malaria parasite infections. Continuous systematic screening and treatment of school-age children in high-transmission settings across the country may reinforce malaria intervention measures.

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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

Malaria Journal ◽

10.1186/s12936-021-03919-4 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Sabin S. Nundu ◽

Richard Culleton ◽

Shirley V. Simpson ◽

Hiroaki Arima ◽

Jean-Jacques Muyembe ◽

...

Keyword(s):

Urban Area ◽

Urban Areas ◽

Malaria Parasite ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

School Age Children ◽

Asymptomatic Malaria ◽

School Age ◽

Republic Of Congo ◽

Symptomatic Malaria

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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Molecular surveillance of Plasmodium falciparum resistance to artemisinin-based combination therapies in the Democratic Republic of Congo

PLoS ONE ◽

10.1371/journal.pone.0179142 ◽

2017 ◽

Vol 12 (6) ◽

pp. e0179142 ◽

Cited By ~ 13

Author(s):

Dieudonné Makaba Mvumbi ◽

Thierry Lengu Bobanga ◽

Jean-Marie Ntumba Kayembe ◽

Georges Lelo Mvumbi ◽

Hippolyte Nani-Tuma Situakibanza ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

Combination Therapies ◽

Molecular Surveillance ◽

Republic Of Congo

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Operation “Artemis”: The First Autonomous EU-led Operation

Academic and Applied Research in Military and Public ◽

10.32565/aarms.2015.1.11 ◽

2015 ◽

Vol 14 (1) ◽

pp. 121-132

Author(s):

János Tomolya

Keyword(s):

United Nations ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

European Security ◽

Republic Of Congo ◽

Autonomous Operation ◽

Republic Of The Congo ◽

Operational Constraints ◽

And Control ◽

The Eu

In June 2003, the EU launched Operation “Artemis”, its first military mission outside Europe and independent of NATO, to the Democratic Republic of Congo. While it ultimately received an EU badge, its origin, command and control were French. The objective of Operation “Artemis” was to contribute to the stabilisation of the security conditions in Bunia, capital of Ituri, to improve the humanitarian situation, and to ensure the protection of displaced persons in the refugee camps in Bunia. Its mandate was to provide a short-term interim force for three months until the transition to the reinforced United Nations Mission in the Democratic Republic of Congo (MONUC – Mission de l’Organisation des Nations Unies en République Démocratique du Congo; English: United Nations Organization Stabilization Mission in the Democratic Republic of the Congo). Although the EU can be said to have passed the first “test” of the European Security and Defence Policy (ESDP) mechanisms for the conduct of an autonomous operation, this test was a limited one. Operational constraints were caused by inadequate strategic lift capabilities and the lack of a strategic reserve.

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