Impact of SARS-CoV-2 Breakthrough Infection on Short-Term CD4 Count Among Adults With HIV in the United States From...

CD4 T cells are critical for reducing disease severity and viral clearance of SARS-CoV-2, which is particularly important among populations that are immune compromised, including people with HIV (PWH). While vaccines are effective, risk and severity of COVID-19 breakthrough infections are higher in people with vs without HIV. Little is known about the effects of SARS-CoV-2 on CD4 counts among PWH after a breakthrough infection.

We evaluated the impact of COVID-19 breakthrough infection on immediate (0-60 days) and short-term (61-180 days) CD4 count from 2020 to 2022 among PWH vaccinated for COVID-19 in the CIVETs-II study (Corona-Infectious-Virus Epidemiology Team). We utilized paired t tests to test for statistically significant changes in CD4 count before and after breakthrough infection and linear mixed effect models to quantify changes in CD4 count following SARS-CoV-2 breakthrough infection.

Among 152 PWH, 37% were White and 40% were ≥55 years of age. Median CD4 count prebreakthrough was 614 cells/mm³, while median postbreakthrough CD4 count was 612 cells/mm³. Most patients had an undetectable HIV viral load (62%). Paired t tests indicated no change in CD4 count prior to breakthrough infection as compared with CD4 count 0 to 60 days (-40 cells/mm³; 95% CI, -86 to 5), or ≥61 days (25 cells/mm³; 95% CI, -11 to 61). Longitudinal trajectories indicated CD4 count rebound ≥61 days following breakthrough infection (112-cell/mm³ increase per 60-day increase, P < .05).

While changes in CD4 counts were observed after breakthrough infection, these results are likely not clinically significant, suggesting that among PWH vaccinated for COVD-19, CD4 count is not substantially affected by breakthrough infections.