Outbreak of Sexually Transmitted Ringworm Emerges in the U.S.

A sexually transmitted version of ringworm is causing concern across the United States. Minnesota health authorities are alerting both medical professionals and the public about an outbreak of a specific fungus, Trichophyton mentagrophytes genotype VII, commonly referred to as TMVII.

According to the Minnesota Department of Health, numerous confirmed and suspected cases of TMVII have been reported in the Twin Cities area since last summer. This might be the largest outbreak of its kind in the country thus far. Local doctors are encouraged to report any cases to the health department, and individuals who suspect they might have it are urged to seek medical assistance and take precautions when it comes to their sexual partners.

“Patients who are worried about having a TMVII-related rash, especially if they’ve had recent sexual contact with others who have a rash, should visit an STI clinic for evaluation and treatment,” the Minnesota Health Department advised in a statement shared recently.

A Rising Fungal Threat

Interestingly, despite its name, ringworm (or tinea) is caused by various types of fungi rather than any type of worm. It generally refers to a specific skin fungal infection characterized by a circular rash. The term can be used to describe different forms of this infection depending on the area it affects; for example, ringworm of the feet is often called athlete’s foot.

Typically, ringworm is easily treated with antifungal medications and is more of a nuisance than a serious health issue. However, a number of new variants, including TMVII, have raised alarms among researchers and health officials. TMVII was initially identified in parts of Europe and Asia a few years back. In June 2024, the first cases in the U.S. were reported in New York City, with sporadic reports coming from other major urban areas since then.

Unlike most ringworm-causing fungi, TMVII appears to spread mainly through close sexual contact. The majority of identified cases so far have involved men who have sex with men. TMVII also seems to cause particularly severe inflammatory rashes that can lead to lasting scars, alongside a heightened risk for secondary infections that may require antibiotics.

The first identified case of TMVII in Minnesota was recorded in July 2025, involving a resident with a rash around the genital area. Following this and similar cases, health officials implemented an enhanced monitoring system to better track the situation. As of February 12, there are 13 confirmed and 27 suspected cases reported, the health department disclosed.

This is likely the largest cluster of TMVII cases reported in the U.S. to date, although officials point out that not all cases are reported, which hampers accurate surveillance data in different regions. Additionally, diagnosing TMVII can be tricky, as its rashes may resemble other skin conditions like eczema or psoriasis.

“Overall, the public risk remains low; however, men who have sex with men, individuals using anonymous apps, and those with prior STI histories may be at higher risk,” the department noted.

Addressing TMVII

On a more encouraging note, TMVII still appears to be manageable with antifungal treatments, unlike some other emerging varieties of ringworm. However, treatment may require extended periods to completely eliminate the infection.

The Minnesota Department of Health emphasizes that early treatment can help prevent more severe illness. Anyone experiencing symptoms, such as itchy, scaly, coin-shaped rashes on areas like the buttocks, genitals, extremities, trunk, or face, should consult a physician, and they should also notify their sexual partners to ensure they seek care, too.

To prevent TMVII, health officials suggest people avoid skin-to-skin contact—or any type of sexual contact—if they or their partners notice any new rashes. Those who are confirmed or suspected to have TMVII should cover affected areas with bandages or clothing and refrain from sharing personal items, like towels, bedding, or razors. It’s also essential to wash hands thoroughly after touching areas that may be affected to minimize the risk of spreading the fungus elsewhere on the body.