Hadijja Nakawooya

SUMMARY: Background: Novel HIV prevention interventions such as long-acting pre-exposure prophylaxis (PrEP) could substantially reduce HIV transmission in Africa. However, efficient implementation in high-prevalence settings where incidence has declined requires an understanding of the contemporary dynamics driving new infections. Methods: We identified incident HIV cases from a longitudinal, population-based cohort in Uganda. We individually matched cases to HIV-negative controls; traced and enrolled reported sexual partners; and enrolled female sex workers (FSWs) from reported venues. Conditional logistic regression, transmission modeling, and phylogenetics were used to characterize transmission networks. Findings: From 2021-2024, 38,899 HIV tests among 22,255 people identified 187 people with incident infections (47.6% male); 164 (88%) were enrolled and matched to 164 HIV-negative controls. Overall, 593 non-sex-worker partners (371 enrolled,62.6%), 146 FSW partners (21 enrolled,14.4%), and 28 venues (208 FSWs enrolled) were reported. Incident infection was most strongly predicted by partnership with a FSW (odds ratio:15.5; 95%CI:3.7-64.8), identified in 43.0% of male cases versus 6.3% of controls. Men with FSW partners had larger sexual networks than men without (median:6 vs 2 partners), and 91.2% of men with FSW partners also had non-sex-worker partners. Transmission modeling attributed 34.4% (95%CI:31.5-36.8%) of all male infections and 80.0% (95%CI:73.2-84.4%) of infections among male clients to sex with FSWs. Oral PrEP use among HIV-negative partners of incident cases was low (8.9% in women; 2.1% in men). Interpretation: Men with FSW partners accounted for a substantial share of incident HIV infections and had markedly higher odds of infection than men without such partnerships. Together with the high potential for onward transmission within male client networks, these findings suggest that inclusion of male clients in long-acting HIV prevention strategies could be highly efficient and impactful. Funding: National Institutes of Health, United States; Gates Foundation; National Health and Medical Research Council, Australia

During the COVID-19 pandemic lockdown, we deployed a rapid, mobile phone-based survey to assess access and participation rates when using mobile phones to collect data on COVID-19 in Rakai, south-central Uganda. We sampled prior Rakai Community Cohort Study (RCCS) participants based on HIV status using mobile phone contacts. We administered a 30-minute phone-based interview to consenting participants to assess their knowledge about different aspects of COVID-19 and their access to care. Our analysis compares the mobile phone survey participation rates with historic participation rates in regular RCCS face-to-face interviews. We supplemented phone survey data with demographic, behavioral, and HIV status data from prior face-to-face RCCS surveys. Phone access in Round 19 of the RCCS was found to be 90.2%, with lower access among older people, and people living with HIV. When including only individuals who participated in the previous RCCS survey round, participation in the face-to-face survey (81.9%) was higher than participation in our phone survey (74.8%, p < .001). Survey participation was higher among people living with HIV compared to HIV-negative individuals (84.0% vs 81.4%, p < .001) in the face-to-face survey, but in the phone survey the reverse was found, with participation rates being higher among HIV-negative individuals compared to people living with HIV (78.0% vs 71.6%, p < .001). It was possible to collect data from an existing population cohort during the lockdown using phones. Phone access was high. Overall participation rates were somewhat lower in the phone survey, notably in people living with HIV, compared to the face-to-face survey.