Observational Cohort Study of Evolving Epidemiologic, Clinical, and Virologic Features of Monkeypox in Southern France

We enrolled 136 patients with laboratory-confirmed monkeypox during June 4–August 31, 2022, at the University Hospital Institute Méditerranée Infection in Marseille, France. The median patient age was 36 years (interquartile range 31–42 years). Of 136 patients, 125 (92%) were men who have sex with men, 15 (11%) reported previous smallpox vaccinations, and 21 (15.5%) were HIV-positive. The most frequent lesion locations were the genitals (68 patients, 53%), perianal region (65 patients, 49%), and oral/perioral area (22 patients, 17%). Lesion locations largely corresponded with the route of contamination. Most (68%) patients had isolated anal, genital, or oral lesions when they were first seen, including 56 (61%) who had >1 positive site without a visible lesion. Concurrent sexually transmitted infections were diagnosed in 19 (15%) patients, and 7 patients (5%) were asymptomatic. We recommend vaccination campaigns, intensified testing for sexually transmitted infections, and increased contact tracing to control the ongoing monkeypox outbreak.