Predictors of HIV Molecular Cluster Membership and Implications for Partner Services.

Public health surveillance data used in HIV molecular cluster analyses lack contextual information that is available from partner services data. Integrating these data sources in retrospective analyses can enrich understanding of the risk profile of people in clusters. In this study, HIV molecular clusters were identified and matched to information on partners and other information gleaned at the time of diagnosis, including co-infection with syphilis. We aimed to produce a more complete understanding of molecular cluster membership in Houston, Texas, a city ranking ninth nationally in rate of new HIV diagnoses that may benefit from retrospective matched analyses between molecular and partner services data to inform future intervention. Data from partner services were matched to molecular HIV records of people newly diagnosed from 2012-2018. By conducting analyses in HIV-TRACE using viral genetic sequences, molecular clusters were detected. Multivariable logistic regression models were used to estimate the association between molecular cluster membership and completion of a partner services interview, number of named partners, and syphilis co-infection. Using data from 4,035 people who had a viral genetic sequence and matched partner services records, molecular cluster membership was not significantly associated with completion of a partner services interview. Among those with sequences who completed a partner services interview (n=3,869), 45.3% (n=1,753) clustered. Molecular cluster membership was significantly associated with naming 1 or 3+ partners compared to not naming any partners (adjusted odds ratio (aOR): 1.27 [95% CI: 1.08, 1.50], P=0.003 and aOR: 1.38 [95% CI: 1.06, 1.81], P=0.02). Alone, co-infection with syphilis was not significantly associated with molecular cluster membership. Syphilis co-infection was associated with molecular cluster membership when coupled with incarceration (aOR: 1.91 [95% CI: 1.08, 3.38], P=0.03), a risk for treatment interruption. Enhanced intervention among those with similar profiles, such as people co-infected with other risks, may be warranted.