Mpox Side Effects: Persistent Physical & Psychosocial Issues Found Post-Infection

Patients with acute mpox infections experienced persistent physical, behavioral, and psychosocial side effects more than a year after illness, a cohort study suggested. Among 154 people with clade II mpox infections, 58% had at least one persistent sequelae, 56% of which were related to appearance, 11 to 18 months after illness, reported Preetam Cholli, MD, of the CDC, and colleagues in the Annals of Internal Medicine. Specifically, 51% had sequelae at one to two sites, 8% were affected at 10 or more sites, 83% had persistent skin discoloration, and 51% had scars. Most had fewer than 10 scars (82%) or discrete pigmented areas (86%). Persistent physical or appearance-related sequelae were more likely in those with 10 or more acute lesions, merged lesions 2 cm or larger, or bacterial superinfection. "Our findings suggest that clinicians should consider more aggressive monitoring and treatment or early dermatology consultation to try to mitigate the possibility of long-term scarring for lesions at or exceeding 2 cm in size," Cholli and team wrote. Co-author Jason Zucker, MD, of Columbia University in New York City, told MedPage Today that "the most surprising finding was the high prevalence of persistent sequelae more than a year after infection, despite the fact that the 2022-2023 U.S. outbreak was largely caused by clade II virus and generally characterized by mild-to-moderate acute disease." Mpox is often framed as a self-limited illness in immunocompetent individuals, Zucker noted. "However, this study demonstrates that long-term physical consequences, particularly scarring and anorectal or urinary symptoms, are common even after clinically uncomplicated infections." The study showed that 13% of post-mpox patients had functional sequelae, of whom 50% and 35% had ongoing anorectal and urinary dysfunction, respectively. As for behavioral and psychosocial side effects, 45% of mpox patients reported an increase in depressive symptoms, while 40% said they'd experienced increased anhedonia since the start of the mpox outbreak. Nearly half (49%) also said they had ongoing challenges with their social life, 19% cited ongoing issues with sexual performance, and 6% said they faced post-mpox employment challenges. Given the percentage of post-mpox patients who reported psychosocial sequelae, clinicians should also screen for depression and social or occupational disruptions and refer to behavioral or wraparound services as needed, the authors noted. Typically transmitted through close, sustained person-to-person physical contact, mpox virus infection can cause skin rash or mucosal lesions that can last 2-4 weeks. Other symptoms include fever, headache, muscle aches, and swollen lymph nodes. There are two types of mpox -- clade I and clade II -- with clade II infections tending to be milder. While there are no FDA-approved treatments for mpox, the modified vaccinia Ankara-Bavarian Nordic vaccine (Jynneos) delivered an estimated adjusted vaccine effectiveness of 66% in people who received two doses. A global outbreak of clade II mpox virus beginning in 2022 led to more than 34,000 confirmed U.S. cases between January 2022 and October 2024. For this cohort study, Cholli and team recruited adults at an academic medical center in New York City and a county health system in Houston. The study included 154 patients diagnosed with clade II mpox infection between May 2022 and January 2023, as well as 201 participants who were never infected. The proportion of participants who reported increased psychobehavioral symptoms was mostly similar between groups. Median age was 35 years, 80% were Black/African American or Hispanic/Latino, 90% were male, 67% were men who reported male-to-male sexual contact, and 56% used public health insurance. At the time of mpox diagnosis, 63% of patients were coinfected with HIV, and 82% were receiving HIV antiretroviral therapy. Nearly one in five (19%) post-mpox patients had received at least one dose of mpox vaccine before their mpox diagnosis. Post-mpox patients also reported experiencing mpox-related stigma. Nearly one in three (30%) said they'd felt hurt by people's reaction to their mpox diagnosis, while 22% said people were hesitant to be around them after their mpox diagnosis. Persistent post-mpox sequelae weren't linked to poorly controlled HIV, Black/African American or Hispanic/Latino race or ethnicity, uninsured status, or unstable housing or homelessness. In addition, mpox vaccination and treatment with the antiviral tecovirimat (Tpoxx) were not associated with persistent sequelae. Those findings reinforce the critical role of mpox vaccination, Zucker said. In addition to reducing the risk and severity of acute disease, he noted, mpox vaccine "may plausibly reduce the burden of long-term sequelae -- highlighting vaccination as an essential component of both individual patient care and broader prevention strategies." Limitations included the study's inclusion of participants from only two U.S. regions, which may not represent the entire population of people affected by mpox. The study's small size may also prevent detection of associations between acute symptoms and other outcomes. The lack of consistent CD4 cell count data didn't allow the researchers to analyze potential links between HIV-related immunocompromise and mpox patients' persistent sequelae.