BACKGROUND: Over 30,000 mpox cases were reported during the 2022 mpox outbreak with many cases occurring among gay, bisexual and other men who have sex with men (MSM). Decreases in U.S. mpox cases were likely accelerated by a combination of vaccination and modifications to sexual behaviors associated with mpox virus transmission. We assessed reports of sexual behavior change among participants receiving mpox vaccination in Washington, DC. METHODS: During August to October 2022, 711 adults aged ≥18 years receiving mpox vaccination at two public health clinics in Washington, DC completed a self-administered questionnaire that asked whether sexual behaviors changed since learning about mpox. We calculated the frequency and percentages of participants reporting an increase, decrease, or no change in 4 of these behaviors by demographic, clinical, and behavioral characteristics with 95% confidence intervals. RESULTS: Overall, between 46% and 61% of participants reported a decrease in sexual behaviors associated with mpox virus transmission, 39% to 54% reported no change in these behaviors, and <1% reported an increase. Approximately 61% reported decreases in one-time sexual encounters (95% confidence interval [CI], 56.8%-64.7%), 54.3% reduced numbers of sex partners (95% CI, 50.4%-58.0%), 53.4% decreased sex via a dating app or sex venue (95% CI, 49.7%-58.0%), and 45.6% reported less group sex (95% CI, 40.4%-50.9%). Reported decreases in these behaviors were higher for MSM than women; in non-Hispanic Black than non-Hispanic White participants; and in participants with human immunodeficiency virus than participants without human immunodeficiency virus. CONCLUSIONS: Most participants receiving mpox vaccination reported decreasing sexual behaviors associated with mpox virus transmission, including groups disproportionately affected by the outbreak.

BACKGROUND: More than 30,000 mpox cases have been confirmed in the United States since May 2022. Mpox cases have disproportionally occurred among adult gay, bisexual, and other men who have sex with men; transgender persons; and Black and Hispanic/Latino persons. We examined knowledge, attitudes, and practices regarding mpox vaccination among adults presenting for vaccination to inform prevention efforts. METHODS: We collected mixed-methods data from a convenience sample of adults presenting for JYNNEOS vaccination at 3 DC Health mpox vaccine clinics during August-October 2022. Survey and interview topics included knowledge about mpox symptoms and vaccine protection, beliefs about vaccine access, and trusted sources of information. RESULTS: In total, 352 participants completed self-administered surveys and 62 participants completed an in-depth interview. Three main themes emerged from survey and interview data. First, most participants had a general understanding about mpox, but gaps remained in comprehensive understanding about mpox symptoms, modes of transmission, vaccine protection, personal risk, and vaccine dosing strategies. Second, participants had high trust in public health agencies. Third, participants wanted more equitable and less stigmatizing access to mpox vaccine services. CONCLUSIONS: Nonstigmatizing, inclusive, and clear communication from trusted sources, including public health agencies, is needed to address mpox knowledge gaps and increase vaccine access and uptake in affected communities. Mpox outreach efforts should continue innovative approaches, including person-level risk assessment tools, to address community needs.