Mpox infection is often followed by lingering physical symptoms

A study of adults diagnosed with mpox between May 2022 and January 2023 reveals that over half of the subjects diagnosed with mpox during the 2022 outbreak had lingering physical effects 11 to 18 months later.

Most of these lingering effects were appearance-related. Some subjects reported ongoing anorectal or urinary problems.

The study was published on January 19, 2026 in Annals of Internal Medicine.

As background, the authors noted, “Mpox, an infection caused by the mpox virus, usually involves a rash that often starts at the site of exposure and can spread anywhere on the body. Other common symptoms include fever, muscle aches, and tiredness. In most people with the infection, symptoms usually last 2 to 4 weeks, and the rash goes through different stages before healing. During 2022 to 2024, there were more than 34,000 mpox cases in the United States, mostly in men who have sex with men. Behavioral changes and vaccination of people at risk for mpox were important in controlling the outbreak. Information about long-term effects of mpox is limited.”

The investigators recruited post-mpox and no-mpox subjects from health centers in New York City and Houston. Each subject completed psychosocial and behavioral self-assessments.

Post-mpox subjects were evaluated according to clinical history and by physical examination.  The researchers classified persisting mpox physical sequelae according to affected tissue, effects on appearance or effects on physical function.

The investigators enrolled 154 post-mpox and 201 no-mpox subjects, Fifty-eight percent (89 of 154) of post-mpox subjects had at least 1 persistent sequelae. Of these, 56% (86 of 154) were appearance-related, in which 51% (44 of 86) occurred at 2 or fewer sites.

Thirteen percent (20 of 154) of post-mpox subjects had functional sequelae, of which 50% (10 of 20) and 35% (7 of 20) were related to ongoing anorectal and urinary dysfunction, respectively.

“Our study provides insights into the persistent impact of mpox sequelae 11 to 18 months after resolution of acute mpox and the ongoing care needs of persons who acquired mpox during the 2022 mpox outbreak in the United States,” the authors concluded.