In this study, we have investigated the diversity of the current HIV-1 stra
ins circulating in Addis Ababa, Ethiopia; in addition, we have evaluated th
e applicability of peptide enzyme-linked immunosorbent assay (ELISA) and he
teroduplex mobility assay (HMA) for HIV-1 subtyping. Previous studies have
indicated that HIV-1 subtype C is the major subtype present in HIV-positive
samples collected from various risk groups between 1988 and 1995 in Addis
Ababa. To assess the possible influx of new HIV-1 subtypes, 150 commercial
sex workers (CSW) reporting in 1997 to two Health Centers in Addis Ababa we
re enrolled in an unlinked anonymous cross-sectional study. Subtyping was p
erformed according to the World Health Organization algorithm of peptide EL
ISA, followed by HMA and DNA sequencing. As a result, the HIV-1 prevalence
among these CSWs was found to be 45% (67 of 150). Of the 67 samples, 66 con
tained HIV-1 of subtype C and only one was of subtype D. This confirms the
persistent overall presence of HIV-1 subtype C in Addis Ababa and a low inf
lux of other subtypes into this location.