ABSTRACT
Surveillance of Plasmodium falciparum crt(K76T) [Pfcrt(K76T)], a resistance marker of chloroquine and, limitedly, amodiaquine, in >4,000 children in northern Ghana revealed a prevalence of 79%. Pfcrt(K76T) was heterogeneously distributed and associated with chloroquine use, low parasitemia, and the dry season. Widespread chloroquine resistance challenges the regional life span of amodiaquine as a partner drug in artemisinin combination therapy.
Subject(s)
Antimalarials/pharmacology , Drug Resistance/genetics , Genes, Protozoan/genetics , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Plasmodium falciparum/genetics , Adolescent , Adult , Aged , Amodiaquine/pharmacology , Animals , Artemisinins/therapeutic use , Child , Chloroquine/pharmacology , Drug Therapy, Combination , Female , Genotype , Ghana/epidemiology , Humans , Lactones/therapeutic use , Male , Middle Aged , Parasitemia/parasitology , Population Surveillance , Sesquiterpenes/therapeutic useABSTRACT
Haptoglobin (Hp) polymorphisms in sub-Saharan Africa have been associated with an increased risk of severe malaria. However, available data are inconclusive. We examined the role of Hp polymorphisms in susceptibility to Plasmodium falciparum infection and to severe malaria in northern Ghana. Three groups each of 290 age and sex-matched children with severe malaria, children with asymptomatic P. falciparum infection and aparasitaemic healthy controls were studied. Hp typing was based on PCR. In all children, Hp1-1, Hp2-1, and Hp2-2 occurred in 32.4%, 54.1%, and 13.5%, respectively. The prevalence of the Hp genotypes did not differ significantly between groups. However, Hp2 alleles were least common in healthy children (0.379), more frequent in parasitaemic controls (0.402), and most common in severe malaria patients (0.434; = 3.7; P = 0.06). In matched pair analysis, no Hp genotype increased the risk of severe malaria. However, using Hp1-1 as a reference, children with Hp2-2 exhibited a slightly increased risk of severe malaria (odds ratio, 1.6; P = 0.04). These results indicate that Hp polymorhisms may have a rather limited influence on the development of severe malaria.
