HIV Type 1 Subtype Distribution, Multiple Infections, Sexual Networks, and Partnership Histories in Female Sex Workers in Kampala, Uganda

Abstract

We investigated for the first time the subtype distribution, prevalence of multiple HIV-1 infections, sexual networks, and partnership histories in a cohort of women engaged in high-risk sexual behavior such as female sex workers (FSWs) and women employed in entertainment facilities. Viral RNA was extracted from blood samples collected from 324 HIV-1-positive women; the gp-41 and pol-IN genes were directly sequenced. Women found to have closely related viruses and those with recombinant viruses were further analyzed in the pol-IN gene by clonal sequencing to determine HIV-1 multiple infections. Individual partnership histories were used to provide information on when sex work was undertaken and where. Subtyping in both gp-41 and pol-IN was successfully done in 210/324 (64.8%) women. Subtype distribution in these two genes was 54.3% (n=114) A/A, 2.9% (n=6) C/C, 24.3% (n=51) D/D, 11.9% (n=25) A/D, 4.8% (n=10) D/A, 0.5% (n=1) C/A, 1.0% (n=2) B/A, and 0.5% (n=1) B/D. Sexual networks were identified in six pairs and one triplet of women with closely related subtype A viruses. Partnership histories showed that women having phylogenetically similar viruses had worked in the same localities. Five cases of multiple infections were confirmed: four dual infections and one triple infection. In this first molecular epidemiology study among FSWs in Kampala, subtype A was the predominant subtype. About 9% of a subgroup had multiple infections. Partnership histories and multiple infections observed in this population suggest sexual mixing of the FSWs and their clients confirming their high-risk characteristics.

Short Communication: HIV Type 1 Transmitted Drug Resistance and Evidence of Transmission Clusters Among Recently Infected Antiretroviral-Naive Individuals from Ugandan Fishing Communities of Lake Victoria

“…These findings were in line with those from other populations in SW Uganda. 30 The mutations seen in our study were associated with resistance to NNRTIs (K103N and V106A). These mutations confer resistance to efavirenz and nevirapine, which form part of standard first line ART regimens in Uganda.…”

Treatment failure and drug resistance is more frequent in HIV-1 subtype D versus subtype A-infected Ugandans over a 10-year study period

“…Subtype A accounts for ∼55% in both patient groups followed by subtype D and subtype C (<4%). Approximately, 10% are unique intersubtype recombinant forms (URFs) in reverse transcriptase but if the entire genome was sequenced, this may go up to more than 30% [27]. Frequency of subtype D infections decreases and subtype A and C increases from west to east and along the shore of Lake Victoria starting from the Tanzanian to the Kenyan border [28].…”

“…As described above, we combined the subtyping analyses on our treatment-naive cohorts ( n = 464) [29–31] with that from other cohorts in Kampala, Uganda [27]. From these analyses ( n = 655), the prevalence of sub-types and recombinant forms were quite consistent over 10 years of study with subtype A infections at 55.5%, B – 0.2%, C – 2.8%, D – 30.1%, and URFs – 11.4% (first bar set, Fig.…”

Concentrated HIV subepidemics in generalized epidemic settings

“…70 Another study in Uganda that combined partnership histories and phylogenetic analysis of female SW identified partial sexual networks and multiple infections, suggesting mixing in these SW and their clients. 71 In the same country, another study suggested that the presence of super transmitters in early HIV infection contributed a disproportionate number of transmissions in a low-risk rural cohort. 72 These kinds of studies are currently being expanded to other large demographic sites in generalized epidemics in Africa, for example the Mochudi treatment as prevention (TasP) trial in Botswana and TasP trial at the Africa Centre in rural South Africa, 73 which has started to produce large molecular epidemiology datasets.…”