Mpox vaccination for men who have sex with men and their differential risk of exposure and infection.

Following the post-COVID-19 reopening of the society with enhanced traveling between countries, people at risk of mpox infection, notably men who have sex with men (MSM) and people living with HIV, are facing increasing threat of virus exposure. Mpox vaccination is an important public health strategy which is provided free in Hong Kong to people at higher risk of infection. Between October 2022 and January 2023, 326 and 184 MSM vaccinees from vaccination sites and HIV specialist clinics in Hong Kong, respectively, were recruited for assessing their infection risks. Apart from the urge to protect one's significant others (68%), 45% were worried about the stigmatizing mpox symptoms if infected. Compared with MSM vaccinees at vaccination site, a lower proportion of MSM vaccinees in HIV care were sexually active in the past 6 months (88% vs 97%), but a higher proportion had recent sexually transmitted infection diagnoses (19% vs 10%) and perceived considerable exposure risk in the following 6 months (40% vs 22%). There were no differences in the perceived effectiveness of mpox vaccination. If optimal supplies of mpox vaccines can be secured, a low threshold approach at vaccination site could enable MSM with different levels of behavioral risks to become protected.