EVIDENCE FOR HIGH GENETIC DIVERSITY AND LONG-TERM ENDEMICITY OF HEPATITIS-C VIRUS GENOTYPE-1 AND GENOTYPE-2 IN WEST-AFRICA

During 1994 and 1995, the prevalence of hepatitis C virus (HCV) and it s genotypes were studied in several rural and urban populations in thr ee West African countries: Guinea, Burkina Faso, and Benin. The follow ing groups were screened for antibodies to HCV (anti-HCV): 459 village rs in the forest region of Guinea; 965 individuals in urban, suburban, and rural populations of the Bobo Dioulasso area, Burkina Faso; and 5 82 blood donors in Cotonou, Benin. In Benin, 60 patients with sickle c ell anemia (30 with and 30 without history of multiple transfusion) an d 13 hospital patients with liver disease were also tested. RT-PCR det ection of HCV-RNA was carried out on all anti-HCV positive samples, fo llowed by genotyping and sequencing of unrecognized subtypes. The prev alence rates of anti-HCV were 1.1% in the Guinean population group, 1. 4% among blood donors in Benin, and 4.9% in residents of Burkina Faso. In patients with sickle cell anemia, five of the 30 polytranfused pat ients (17%) had anti-HCV, whereas none of the patients without a histo ry of blood transfusion had anti-HCV (P < 0.05). Among the 13 patients with liver disease, five had anti-HCV, of whom four had history of bl ood transfusion. HCV-RNA was detected in 41 anti-HCV positive sera. Al l belonged to genotypes 1 or 2, with a high genomic diversity; 18 diff erent subtypes were identified, including 2c, 2d, and 16 new subtypes. Such genetic diversity poses a challenge for vaccine development and also implies that HCV infection is long-established in these West Afri can regions. (C) 1998 Wiley-Liss, Inc.