Larson Boundenga

By Jean Bernard Lekana-Douki and Larson Boundenga

Malaria is one the world’s most widespread lethal diseases. Plasmodium falciparum, P. vivax, P. ovale, P. malariae and P. knowlesi induce human pathology. These species could be differentially diagnosed using the genotyping of cytochrome b, Pfdhfr and RNA 18S. The persistence of P. falciparum, the most lethal parasite, is mainly due to antimalarial drug resistance. Indeed, a few years after the start of the ambitious malaria eradication program in 1960, chloroquine resistance emerged in Asia and spread widely in all the endemic areas. It was associated with genotypes in P. falciparum chloroquine resistance transporter (CVIET, SVMNT, CVMNT, CVIDT, SVIET and CVMET). The use of new drugs such as sulfadoxine-pyrimethamine (SP) leads quickly to SP-resistant parasites associated with genotypes on P. falciparum DiHydroFolate reductase (I51-R59-N108-I164) and P. falciparum DiHydroPteroate synthetase (436-437-580-613). Recently, the delay of parasite clearance has been described with artemisinine (the most efficacious antimalarial drug). This resistance was associated with the K13 propeller genotype. Since malaria species and antimalarial drug resistance markers could be characterized using nucleic acid sequences, genotyping is needed for malarial monitoring of species distribution and antimalarial drug resistance.

Part of the book: Genotyping

By Boundenga Larson

Malaria is a protozoan disease caused by a parasite belonging to Plasmodium genus. Five species are known to infect humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium knowlesi, Plasmodium ovale, and Plasmodium malariae. Among these species, Plasmodium falciparum and Plasmodium vivax account for more than 95% of all human malaria infections and thus pose a serious public health challenge. Plasmodium falciparum is highly prevalent in sub-Saharan Africa, while Plasmodium vivax is rare in sub-Saharan Africa but endemic in many parts of Asia. The recent studies using the development of molecular tools have shown that a large diversity of malaria parasites circulate among the nonhuman primates and certainly present a similarity with human parasites. For a long time, the question of the origin of its parasites that infect human population has been the subject of much debate. Today, it would seem that both most virulent agents of human malaria would come from African apes. Thus, this chapter tries to review available data about the origin of these two Plasmodium species.

Part of the book: Malaria