Sexual Networks and Behavioral Characteristics of HIV-Positive Male Military Members, Female Sex Workers, and Male Civilians.

Military members and female sex workers (FSWs) may be more likely to acquire or transmit HIV. Mapping HIV transmission across these high-risk populations and identifying behaviors associated with sexual network clustering are needed for effective HIV prevention approaches. A cross-sectional study recruited participants newly diagnosed with HIV among militaries, civilians, and FSWs in Zambia, Senegal, and Democratic Republic of the Congo (DRC). Participants were interviewed on behaviors and provided blood samples for HIV-1 partial pol sequencing. Genetic-distance based network analyses inferred putative relationships between HIV-1 partial pol sequences. Bivariate logistic regression models identified variables associated with clustering in a sexual network. 908 participants were included (n = 313 FSWs, n = 297 military, n = 298 civilians). 311 blood samples were sequenced and had survey data, of which 93 (29.9%) were genetically linked, forming 36 transmission clusters. All but one cluster were comprised of participants from the same country, including one large cluster (n = 12; 9 FSWs and 3 civilians) from DRC. A large mixed-country cluster (n = 9) including 7 men (4 civilians, 3 military) and 2 FSWs was observed. The odds of clustering in a sexual network were elevated for DRC participants, FSWs, and those cohabitating with a sexual partner. Findings underscore the importance of identifying linkages in high-risk populations to develop tailored HIV prevention strategies. Linkages across risk groups and countries illustrate the potential role of mobile populations in HIV transmission and acquisition. Larger studies including HIV recency testing may better elucidate biological and behavioral interactions between military, civilians, and FSWs.