Differential influences of mpox illness representation on sexual behaviors among gay, bisexual, and other men who have sex with men in Beijing and Hong Kong

Mpox perceptions may influence the onset of sexual behaviors (e.g., condomless anal sex [CAS] with men, number of male sex partners, and sexualized drug use) among gay, bisexual, and other men who have sex with men (GBMSM). However, no studies have examined how mpox illness representations relate to sexual behaviors. This study examined the associations between mpox illness representations and presence of sexual behaviors among GBMSM in Beijing and Hong Kong. This secondary analysis of a cross-sectional survey conducted between November 2023 and March 2024 among GBMSM in Beijing and Hong Kong. Eligible participants were Chinese males aged ≥ 18 years who had anal sex with at least one man in the past six months. Participants were recruited through venue-based outreach, online platforms, and peer referrals, and completed a structured telephone interview. Multivariable logistic and negative binomial regression models assessed the associations between mpox illness representations and sexual behaviors. A total of 524 GBMSM in Beijing and 613 in Hong Kong participated (response rates: 87% and 86%). After adjustment, GBMSM in Beijing perceived more severe consequences, longer expected illness timeline, greater personal control, more concern, and better understanding related to mpox than their counterparts in Hong Kong. In Beijing, better understanding of mpox (coherence) was associated with lower odds of CAS with men (adjusted odds ratio = 0.92, 95% CI: 0.87–0.98), while longer expected illness timeline (timeline) (incidence rate ratio [IRR] = 0.96, 95% CI: 0.93–1.00), anticipating more severe symptoms if infected (identity) (IRR = 0.94, 95% CI: 0.90–0.97) and stronger negative emotions (emotion) (IRR = 0.94, 95% CI: 0.90–0.98) were associated with fewer male sex partners. In contrast, greater personal control (IRR = 1.06, 95% CI: 1.02–1.10) was associated with higher number of male sex partners in Beijing. Associations between mpox-related illness perceptions and sexual behaviors were observed between GBMSM in Beijing but were not detected in Hong Kong. Future studies may explore whether modifying mpox-related illness representation is helpful to promote safe sexual behaviors among GBMSM in Beijing. Not applicable.