An unusual fungal skin infection is drawing the attention of health authorities in the United States. In the state of Minnesota, clinicians have documented what appears to be the largest known outbreak of a sexually transmitted form of ringworm to date. More than 30 confirmed or suspected cases have been reported around the Minneapolis metropolitan area since the summer of 2025. According to the CDC, documented cases so far appear disproportionately among men who have sex with men (MSM).
The culprit is a specific fungal strain named Trichophyton mentagrophytes Genotype VII (TMVII). It causes a type of ringworm — a fungal skin infection — that can show up mainly in the genital, buttock, or abdominal regions and often produces painful, itchy skin changes. The fungus spreads primarily through close skin-to-skin contact, especially during sex.
Prolonged Therapy
Health authorities note that while the infection is treatable, the therapy can be lengthy: in many cases, those affected must take antifungal medications for several weeks to up to three months.
The first known U.S. infection was diagnosed in New York City in 2024. Since then, isolated cases have been reported in other major cities. The fungus has also appeared in China and Europe. The CDC describes the infection as “a newly emerging fungus,” originally described in travelers who returned after sexual contact in Thailand.
Another issue: the infection is often mistaken for other skin conditions such as eczema or psoriasis. This can delay diagnosis — and keep patients contagious longer.
Health authorities therefore urge people with unusual genital or buttock rashes to seek medical advice. Those undergoing treatment should also abstain from sex and avoid sharing clothing, towels, or bedding to prevent further spread of the fungus.
