Multisite Mpox Infection and Viral Dynamics Among Persons With HIV in Metro Atlanta

Abstract

The 2022 mpox outbreak primarily involved sexual transmission among men who have sex with men and disproportionately affected persons with human immunodeficiency virus (HIV). We examined viral dynamics and clinical features in a cohort evaluated for mpox infection at a comprehensive HIV clinic in Atlanta, Georgia. Viral DNA was found in 8 oropharyngeal and 5 anorectal specimens among 10 mpox cases confirmed by lesion swab polymerase chain reaction. Within-participant anatomic site of lowest cycle threshold (Ct) value varied, and lower Ct values were found in oropharyngeal and anorectal swabs when corresponding symptoms were present. This provides insight into mpox infection across multiple anatomic sites among people with HIV.

Keywords: HIV; anorectal; mpox; oropharyngeal; viral load.

Figure 1.

Viral load assessment for participants enrolled in the study. A, 10 of 20 enrolled participants were diagnosed with mpox. Cutaneous lesion, oral, and rectal swabs were collected and tested for Monkeypox virus DNA. Polymerase chain reaction (PCR)–positive swabs were tested in a cell culture infectivity assay. B, Within-participant comparison shows the highest viral load varied across the cohort. PCR-negative specimens were not tested in the cell culture assay. Comparison of cycle threshold value at each anatomic site based on the presence or absence of pharyngitis (C) or rectal symptoms (D) suggests that higher viral loads at the corresponding anatomic site may be associated with the presence of symptoms. *One participant had the presence of a perianal lesion documented in the encounter physical examination, but whether rectal symptoms were present is unknown. Abbreviations: Ct, cycle threshold; FFA, focus-forming infectivity assay; NT, not tested in focus-forming infectivity assay; NVAR, nonvariola orthopoxvirus; PCR, polymerase chain reaction.

Figure 2.

Infectivity and sequencing studies show replication-competent virus at all sample sites and greater genetic diversity in oral specimens. A, Example of infectivity assay for 3 specimens from participant 16, all of which showed cytopathic effect in 100% of 8 assay replicates (infectivity assay results for all specimens are shown in Supplementary Figure 3). B, Phylogenetic tree shows clustering by participant, except that oral specimen for participants 9 and 16 clustered away from the corresponding lesion and rectal specimens. Ultra-fast bootstrap of 95% or higher is indicated with a black circle at the cluster node. C, Average Shannon entropy from each sample suggests greater viral diversity in oral swabs.