A crucial first step toward obtaining HIV care is knowing one’s own HIV status. A large proportion of HIV-infected persons in South Africa do not know their status, and men are typically less likely than women to be aware of their serostatus. Expansion of HIV treatment may increase disclosure, reduce stigma, and increase testing. We estimate how a person’s ART eligibility affects their household member’s HIV status knowledge.
We conducted a regression discontinuity analysis that exploits the CD4 count threshold for ART eligibility in South Africa to evaluate the causal intent-to-treat (ITT) effect of ART eligibility on the patient’s household members. Using data from 2007-2012 in a large population-based cohort in rural South Africa run by the Africa Health Research Institute, we compared outcomes among household members of patients who had a CD4 count just below the 200-cell threshold (and were thus eligible for ART) with household members of patients with CD4 counts just above the cut-off (and were thus less likely to be eligible for ART). We assessed effects on self-reported knowledge of HIV status and conducted sub-group analyses by the gender of the patient and the gender of household members.
ART led to a large increase in HIV status knowledge among the patient’s male household members (ITT causal effect of 17 percentage points, 95% CI 12, 22). This effect represents a three-fold increase in the likelihood that a male household member reported knowing their HIV status relative to the baseline rate of 7%. The effect was concentrated among men living in households where women became eligible for ART, and there was no effect for female household members. The results for men were robust to sensitivity analyses including variation in bandwidths and inclusion of covariates.
Living with someone who is eligible for ART increased men’s likelihood of reporting that they knew their HIV status. This effect may be due to increased testing, or to updating of beliefs about HIV status based on partner’s status even in the absence of test results. In designing the next generation of ART programs, such household-level spillover effects could be harnessed to increase HIV status knowledge and ART uptake among men. Although prior studies have noted a correlation between ART expansion and testing rates, this study is among the first to causally link ART initiation to increased awareness of HIV status among household members.