All persons with HIV, irrespective of CD4 count or HIV viral suppression, are at higher risk of breakthrough infections, suggests a recent study published in JAMA Network Open.¹

A total of 113,994 adults, ≥18 years, who had been fully vaccinated against Covid-19 till June 30, 2021, were screened. Of these 33,029 had HIV and 80,965 did not have HIV. Data was sourced from the CIVET II cohort, which includes four longitudinal cohorts from academic health centers and integrated health systems. Majority of the participants were male and most (70%) were aged 55 years and older. The study subjects were followed up till December 2021. Majority (93%) of them had taken two doses of mRNA vaccine and the remaining had received the single dose J&J vaccine.

Results showed that the risk of breakthrough infection was 28% higher in HIV-positive patients with adjusted hazard ratio (aHR) of 1.28. Even though the cumulative incidence of breakthrough infections was low after 9 months at 3.8%, it was still higher in HIV patients versus those without HIV; 4.4% vs 3.5%, respectively. J&J vaccine recipients were at the highest risk (~6%) followed by those who had taken the Pfizer-BioNTech (4.4%) and Moderna vaccines (~3%). Factors that increased the likelihood of breakthrough infections were younger age 45 years and below and not taking an additional vaccine dose. A history of Covid-19 was associated with nearly 2-fold increased risk with aHR 1.96. HIV patients who had a CD cell count of ≥500 cells/mm³ had lesser odds of breakthrough infections.

The CDC now recommends an extra dose of the vaccine in the primary series, in addition to the booster, for the moderately-to-severely immunocompromised persons. Among HIV patients, only those with “advanced or untreated HIV infection” with CD4 count of less than 200 cells/mm3 are currently eligible for the additional dose. This study shows that persons with HIV are at higher risk of breakthrough infections compared to those without HIV and an additional primary vaccine dose was protective against infection with SARS-CoV-2 strains that were in circulation before December 2021. Hence, the authors suggest that all persons with HIV should be offered the additional dose in the primary vaccination series.

Reference

1. Coburn SB, et al; Corona-Infectious-Virus Epidemiology Team (CIVETs) of the NA-ACCORD of IeDEA. Analysis of Postvaccination Breakthrough COVID-19 Infections Among Adults With HIV in the United States. JAMA Netw Open. 2022 Jun 1;5(6):e2215934. doi: 10.1001/jamanetworkopen.2022.15934.