The rates of HIV-1 superinfection and primary HIV-1 infection are similar in female sex workers in Uganda

Abstract

To determine and compare the rates of HIV superinfection and primary HIV infection in high-risk female sex workers in Kampala, Uganda. Design—A retrospective analysis of individuals who participated in a clinical cohort study among high-risk female sex workers in Kampala, Uganda. Methods—Plasma samples from HIV-infected female sex workers (FSW) in Kampala, Uganda were examined with next-generation sequencing of the p24 and gp41HIV genomic regions for the occurrence of superinfection. Primary HIV incidence was determined from initially HIV-uninfected FSW from the same cohort, and incidence rate ratios were compared. Results—The rate of superinfection in these women (7/85; 3.4/100py) was not significantly different from the rate of primary infection in the same population (3.7/100py; IRR=0.91, p=0.42). Seven women also entered the study dual infected (16.5% either dual or superinfected). The women with any presence of dual infection were more likely to report sex work as their only source of income (p=0.05), and trended to be older and more likely to be widowed (p=0.07). Conclusions—In this cohort of female sex workers, HIV superinfection occurred at a high rate and was similar to that of primary HIV infection. These results differ from a similar study of high-risk female bar-workers in Kenya that found the rate of superinfection to be significantly lower than the rate of primary HIV infection.