Summary:To investigate the prevalence of the HIV-1 subtypes in different populations from Salvador, Bahia, Brazil, blood samples from 72 HIV-1-seropositive injecting drug users (IDUs) and 62 individuals infected sexually were analyzed using the heteroduplex mobility assay (HMA). In the IDU group, 89.5% were classified as subtype B, 3% as subtype F, and 7.5% showed a B/F HMA profile. In the sexual transmission (ST) group, 95% were identified as B subtype, 3.4% showed a B/F profile, and 1.6% a B/C/E HMA profile. All Brazilian samples that showed multiple reactivities in the HMA analysis clustered on sequencing with B North American/European HIV-1 isolates in the phylogenetic analysis, whereas the F subtypes clustered with F Brazilian HIV-1 isolates. Serologic reactivities of IDU's sera were examined using a panel of synthetic V3 loop peptides representative of the different HIV-1 subtypes. No difference in serologic reactivity between F and B subtype plasma could be observed. Predominance of HIV-1 subtype B was identified in both study groups, whereas subtype F was detected only among IDUs in a frequency lower than described for other Brazilian regions.
Address correspondence and reprint requests to J. C. Couto-Fernandez, Laboratory of AIDS and Molecular Immunology, Department of Immunology, Oswaldo Cruz Foundation, Av. Brasil 4365, Manguinhos, Rio de Janeiro, Brazil 21045-900; email: email@example.com.
Manuscript received March 15, 1999; accepted July 29, 1999.
© 1999 Lippincott Williams & Wilkins, Inc.