title: Influence of haemoglobins S and C on predominantly asymptomatic Plasmodium infections in northern Ghana.
abstract: The haemoglobin (Hb) variants HbS and HbC protect against severe malaria. Yet, the influence particularly of HbC on asymptomatic or mild Plasmodium infection is not well established. In a dry season cross-sectional survey among 2108 children aged 0.5-9 years in the Northern Region of Ghana, Plasmodium species and density, as well as Hb, were analysed with respect to Hb genotypes. HbAC occurred in 19.7% and HbAS in 7.4% (HbSC, 0.8%; HbCC, 0.8%; HbSS, 0.3%). Overall, 56% of the children had microscopically visible parasitaemia. By PCR, P. falciparum, P. malariae, and P. ovale were present in 74.5%, 9.7%, and 5.5%, respectively. Febrile parasitaemia was rare (2.8%) but anaemia (Hb<11g/dL) frequent (59.3%). Children with HbAA and HbAC showed virtually identical malariometric parameters. In contrast, children with HbAS had significantly less parasitaemia, lower parasite densities, and a higher proportion of submicroscopic P. falciparum infection. Remarkably, in children with HbCC, P. malariae infection occurred in 37.5% (adjusted odds ratio (aOR), 5.8; 95% CI, 1.8-18.8) and P. ovale in 18.8% (aOR, 3.61; 95% CI, 0.97-13.5). In this population with predominantly asymptomatic Plasmodium infection, HbAC shows no discernible effect on malaria-related parameters. Homozygous HbC, in contrast, confers an increased risk of P. malariae infection which conceivably may modulate falciparum malaria.
authors.affiliation: Charité - University Medicine Berlin, Spandauer Damm 130, 14050 Berlin, Germany. ina.danquah@charite.de
authors.forename: Ina
authors.initials: I
authors.lastname: Danquah
authors.forename: Peter
authors.initials: P
authors.lastname: Ziniel
authors.forename: Teunis A
authors.initials: TA
authors.lastname: Eggelte
authors.forename: Stephan
authors.initials: S
authors.lastname: Ehrhardt
authors.forename: Frank P
authors.initials: FP
authors.lastname: Mockenhaupt
mesh_terms: D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005869:Ghana / Q000453:epidemiology; D006444:Hemoglobin C / Q000235:genetics*; D006451:Hemoglobin, Sickle / Q000235:genetics*; D006801:Humans; D007223:Infant; D008288:Malaria / Q000097:blood* / Q000453:epidemiology / Q000235:genetics; D016778:Malaria, Falciparum / Q000097:blood* / Q000453:epidemiology / Q000235:genetics; D008297:Male; D018512:Parasitemia / Q000097:blood*; D012805:Sickle Cell Trait / Q000097:blood / Q000235:genetics
chemical_list: D006451:Hemoglobin, Sickle; D006444:Hemoglobin C