Background:
Mpox is typically a self-limited infection; however, HIV-associated immunosuppression increases the risk of severe illness. For persons with HIV (PWH), correlates of risk for severe illness, such as illness severe enough to warrant hospitalization, have not been well characterized. Such data could help determine which PWH with mpox should be prioritized for close monitoring and care including early or empiric tecovirimat treatment.
Methods:
We characterized the HIV status of all reported cases of mpox in Georgia from 5/31/2022–10/31/2022 by linking surveillance data for mpox cases with HIV cases, including HIV laboratory results. We used a retrospective cohort design and a modified Poisson regression model with a log-link and robust variance estimates to calculate relative risks (RRs) for hospitalization with mpox. The predictor variable captured 1) most recent CD4 cell count (CD4) in the year prior (< 350 and ≥350 cells/mm3) and 2) engagement in care defined as any HIV laboratory results (CD4 or viral load) in the year prior to mpox onset.
Results:
Among 1,921 mpox cases in Georgia, 1,851 (96%) were among cisgender men, and 1,124 (59%) were among PWH of whom 214 (19%) had a CD4 count < 350 cells/mm3 and 189 (17%) had an unsuppressed viral load ( >200 copies/ml) in the year prior to mpox onset. Among 121 persons reported as hospitalized with mpox to GDPH, 84 (69%) were PWH, of whom 32 (26%) had CD4 < 350 cells/mm3 and 15 (12%) had no CD4 or VL results in the year prior. Common reasons for hospitalization included pain control (37%), breathing problems (13%), and treatment of a secondary infection (11%). Among PWH, persons with low CD4 count had increased risk of hospitalization starting around CD4 < 350 cells/mm3 [Figure]. Risk for hospitalization among PWH with CD4 >350 cells/mm3 was similar to that for persons without HIV (RR 1.0, 95% confidence intervals [CI] 0.6-1.5); however, PWH with CD4 < 350 cells/mm3 were more likely to be hospitalized (RR 3.2, 95% CI 2.1-5.1). PWH without recent HIV laboratory results were also more likely to be hospitalized (RR 2.4, 95% CI 1.3-4.2).
Conclusions:
PWH were more likely to be hospitalized with mpox if their most recent CD4 was < 350 cells/mm3 or if they were not engaged in care (using laboratory criteria in the past year as a proxy). For PWH diagnosed with mpox who have CD4 < 350 cells/mm3 or who are not engaged in HIV care, clinicians should closely monitor illness and consider early treatment with medical countermeasures such as tecovirimat.
Crude risk of hospitalization with mpox among persons with HIV by CD4 count produced with locally estimated scatterplot smoothing, shaded area is 95% confidence interval