Abstract
OBJECTIVES: This study aims to characterize and compare COVID-19 breakthrough infections between people living with and without HIV across different phases of the pandemic. METHODS: Using statewide HIV cohort data, the study population included adult residents in South Carolina (SC) (>18 years old) who were fully vaccinated between January 02, 2021 and April 14, 2022 when Alpha, Delta, and Omicron variants were circulating in SC. We used the Cox proportional hazard model to investigate the association between HIV infection and breakthrough infection, adjusting for relevant covariates. RESULTS: Among 2,144,415 vaccinated individuals, 8,335 were people living with HIV (PLWH) and 2,136,080 were people without HIV (PWoH). After propensity score matching, HIV infection was not significantly associated with breakthrough infection rate. However, when comparing breakthrough infections among individuals without any booster dose, PLWH had a higher risk of breakthrough infections (adjusted Hazard Ration: 1.19; 95% confidence interval: 1.03-1.39). Compared to PWoH, PLWH with high levels of clusters of differentiation 4 (CD4) count or viral suppression were not associated with breakthrough infections. CONCLUSIONS: Our findings do not support a broad conclusion that COVID-19 vaccine effectiveness is lower among PLWH, while we did find that PLWH had a higher risk of breakthrough infection compared to PWoH if they did not receive a booster dose.