Emergence of new HIV-1 subtypes other than Subtype C among antenatal women in Lusaka, Zambia.

Molecular epidemiology of HIV-1 in Zambia was investigated by direct sequencing of PCR products from samples collected from antenatal attendees in Lusaka, Zambia. One hundred and forty samples were initially screened for HIV, using antibody assays. Thirty-three (23.6%) samples were HIV-1 positive. Sequences of the HIV-1 env gp120 region were obtained from 28 of 33 (85%) HIV-1-positive samples. Twenty-six of the 28 sequences were HIV-1 env subtype C-like as previously reported. However, one HIV-1 env subtype D-like virus and one HIV-1 env subtype G-like virus were identified. This is the first time that these two HIV-1 env subtype viruses have been identified in Zambia, suggesting that more subtypes could be in existence.