Malaria remains a diagnostic and therapeutic challenge in many endemic regions of sub-Saharan Africa. It is one of the most important causes of morbidity and mortality, especially in children <5 years. Plasmodium falciparum is responsible for the majority of severe malaria cases in sub-Saharan Africa, but is not the exclusive one.

The objective of the study was to assess the prevalence of Plasmodium spp. in BaAka Pygmies with clinical symptoms of malaria, and define the percentage distribution of infections caused by species other than P. falciparum in order to assess the need for diversification of malaria treatment protocols.

Material and methods:
The study was conducted during the dry and rainy seasons in 2018 and involved a group of 540 symptomatic BaAka Pygmies, patients of both genders, aged 1–75-years-old. Two diagnostic methods for detecting Plasmodium in the bloodstream were used: RDTs targeting HRP2-protein specific for P. falciparum, and PCR assays aimed at detecting P. falciparum, P. vivax, P. ovale, P. malariae species.

Only 40.5% of symptomatic patients tested with RDTs for P. falciparum infections were positive. Molecular tests (PCR) confirmed P. falciparum in 94.8% of the samples and also revealed the genetic material of P. malariae (11.1%), P. ovale (9.8%), and P. vivax (0.7%). BaAka Pygmies aged <5 years of age dominated in patients with positive results; the common clinical symptoms reported by the sick individuals were fever, shivers and fatigue.

The study suggests the need for introducing accurate diagnostic methods for the diagnosis of malaria and the revision of malaria treatment protocols. Assessment of the Pfhrp2/Pfhrp3 deletions is necessary for evaluating malaria epidemiology in Central Africa.

CAR – Central African Republic; WHO – World Health Organization; PCR – polymerase chain reaction; RDT – rapid diagnostic test; HRP2 – histidine rich protein 2; ACT – artemisinin-combined therapy; NGO – non–governmental organization; FUO – fever of unknown origin
The authors would like to thank Emmanuel Wane, director of the ADIH Hospital in Bayanga for assistance obtaining agreement for the research from the Ministry of Research and Innovative Technologies in the Central African Republic. The research received financial support from Ministry of Science and Higher Education in Warsaw, Poland (Grant No. 556/2018). The ministry had no role in study design, collection and analyse of data, decision to publish, or preparation of the manuscript. The study entitled Assessment of the prevalence Plasmodium infections in sub-Saharan Africa in symptomatic BaAka Pygmies inhabiting the rural Dzanga Sangha region in the Central African Republic was approved by the Bioethics Committee at the Military Institute of Medicine, Warsaw, Poland (Resolution No. 137/WIM/2018). The study entitled Evaluation de la survenue d’infections à Plasmodium spp dans la population de Pygmées BaAka des zones forestières de la République Centrafricaine was approved by the Ministry of Research and Innovative Technologies, Bangui, Central African Republic (Resolution No. 176/ MERSIT/DIRCAB/CB.18).
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