Genetic diversity of GBV-C/HGV strains among HIV infected-IVDU and blood donors from Buenos Aires, Argentina.

GBV-C/HGV RNA was investigated in serum samples from 70 HIV(+) intravenous drug users (IVDU), as well as from 200 blood donors from Buenos Aires, Argentina. Viral RNA was demonstrated in 21 IVDU by reverse transcription-nested PCR of the 5' UTR. c-DNA amplified products were analyzed and their sequences compared with those downloaded from GenBank. A phylogenetic tree based on 171 sequences demonstrated the presence of three major genogroups, including two subgroups, within local samples, i.e. group 1 (n=1), 2a (n=11), 2b (n=4) and 3 (n=5). These results agreed entirely with those obtained by a novel RFLP (J. Clin. Microbiol. 37, 1340-1347, 1999) of the same 5' UTR amplicons. As expected, GBV-C/HGV RNA prevalence was significantly higher among IVDU than among blood donors (P<0.0001), although within the latter group an unexpectedly high rate was also detected, since 11 of 200 sera (5.5%) proved positive. These viral isolates were ascribed either to subgroup 2a (n=5), subgroup 2b (n=5) or genogroup 3 (n=1). Briefly, this partial view of GBV-C/HGV molecular epidemiology in Argentina shows: (i) different rates of GBV-C/HGV infection within both IVDU and blood donors; (ii) a high prevalence of viral RNA among blood donors; and (iii) a predominant circulation of genogroup 2, with minor contribution of groups 3 and 1.