Epidemiology of the 2022 Mpox Outbreak in the US Veterans Health Administration

In May 2022, mpox cases were reported in nonendemic countries, including the United States. We examined mpox infections in the Veterans Health Administration (VHA).

Mpox diagnostic and whole genome sequencing (WGS) results, demographics, risk factors, hospitalizations, exposures, deaths, and pharmacy and immunization data were obtained from VHA data sources (23 May 2022-31 May 2023).

Of 1144 Veterans tested, 251 (21.9%) were presumptive positive for nonvariola orthopoxvirus (NVO) or confirmed positive for NVO and Monkeypox virus (MPXV). Incidence rate was 7.5 per 100 000 Veterans in care, with the highest rate observed in Veterans aged 25-34 years (13.83 cases per 100 000). Higher odds of NVO or NVO/MPXV positivity was associated with male sex; non-Hispanic Black race/ethnicity; syphilis or human immunodeficiency virus (HIV) positivity; or genital/rectal sample site, whereas older age and vaccination with JYNNEOS or vaccinia (smallpox) had lower odds. Among 209 with confirmatory testing, 90.4% reported intimate contact and/or an epidemiological link, 84.5% were men who have sex with men (MSM), 24.2% received tecovirimat, and 8.1% were hospitalized with 1 death. Eighty-six sequenced samples had evaluable WGS results. All were clade IIb, representing 10 different lineages from 20 states and the District of Columbia.

Mpox affected younger, MSM, non-Hispanic Black, and HIV/syphilis-positive men among US Veterans. Viral diversity was noted across geographic regions. At-risk Veterans would benefit from vaccination and risk reduction strategies for mpox and other sexually transmitted infections.