The epidemiology of hepatitis C (HCV), especially on the African continent, is not well known. In this study, we investigated the presence of antibodies to HCV in 685 out-patients, seen in several health care centers or hospitals in different regions in Burundi from January to February 1991. Serological tests of the second generation were used. The global prevalence varied from 3.2% to 14.1% according to the center. Urban seroprevalence tended to be higher than rural prevalence. Also, with increasing age, a higher prevalence was observed. Anti-HCV antibodies were absent in patients younger than 21, while specific antibodies were detected in 23.1% of patients older than 50. Although the prevalence in men (10.4%) was higher than in women (7.4%), this difference was nor statistically significant. Taking into account the selection of subjects participating in this evaluation, the results can not be extrapolated to the general population. No association between HCV and human immunodeficiency virus (HIV) was seen in this study. In contrast to previously described results from studies using reagents of the first generation, no cross-reactions were observed with anti-malarial antibodies.

An anti-HIV-1/HIV-2 line immunoassay (LIA), using peptides and recombinant antigens was evaluated against commercially available Western blot tests for HIV-1 and HIV-2 antibodies. Two thousand one hundred and ten sera of European, African, and South American origin were used in the evaluation. The panel included 1066 sera with antibodies to HIV-1, 192 sera with antibodies to HIV-2, and 64 sera with antibodies to both. Using Western blot results interpreted according to the WHO criteria as a reference standard, the overall specificity obtained by this LIA was 100 % and the sensitivity was 99.77 % (97.51-100 % for 95 % confidence limits) when sera dually reactive in Western blot were included. Of the three sera negative in the LIA but positive in HIV-1 WB, two could be retested in a radioimmunoprecipitation assay and were negative. When dually reactive sera in the Western blot (WHO) were included, the LIA yielded 9.9 % indeterminate results as compared with 15.5 % for both assays (x2=29.30; p<0.001). Although only one HIV-2 specific peptide antigen (gp36) was used, the LIA yielded a specificity of 100 % and a sensitivity of 100 % as compared with the HIV-2 Western blot assay. When indeterminate results were included, the overall agreement between the LIA and the HIV-1 and HIV-2 Western blot (WHO criteria) was 89.9 % and 90.1 % respectively. These results indicate that the LIA provides reliable simultaneous detection of antibodies to HIV-1 and HIV-2, and at a cost which is substantially lower than the cost of Western blot tests.