1st case of sexually-transmitted form of ringworm reported in US

FILE - Photomicrograph of zoophilic fungus Trichophyton mentagrophytes. Image courtesy CDC/Dr. Leanor Haley. (Photo via Smith Collection/Gado/Getty Images).

A new and "highly contagious" form of ringworm likely spread through sex has been reported in the U.S. for the first time, health officials warned. 

The rare fungus, called trichophyton mentagrophytes type VII (TMVII), was detected in a man in his 30s in New York City, according to a study published on June 5 in the journal JAMA Dermatology. The man reported having sex with multiple male partners during a trip to England, Greece and California.

The man developed tinea, also known as ringworm, on his penis, buttocks, and limbs, health officials said. 

"This sexually transmitted form of ringworm has been increasingly diagnosed throughout Europe, with 13 instances reported in France in 2023, mostly in men who have sex with men," doctors at NYU Langone Health in New York City said of the rare infection. 

"Notably, the man in the current study said he had sex with multiple male partners during his travels, none of whom reported similar skin issues," they added.

Tests revealed he had the fungus and doctors prescribed him standard antifungal oral medications, but it took his body four and a half months to clear it.

The man took fluconazole for four weeks without improvement before moving on to terbinafine for six weeks and then itraconazole for eight weeks.

Doctors said he did not have any other infections that could have made the problem worse.

Dr. John Zampella of NYU Langone Health, who co-authored the study, noted how infections caused by TMVII are difficult to treat and can take months to clear up. However, they so far appear to respond to standard antifungal therapies, such as terbinafine.

"Since patients are often reluctant to discuss genital problems, physicians need to directly ask about rashes around the groin and buttocks, especially for those who are sexually active, have recently traveled abroad, and report itchy areas elsewhere on the body," Zampella said.

Meanwhile, study lead author and dermatologist Dr. Avrom Caplan with NYU Grossman School of Medicine said a new skin condition explored in his other new report presents a greater challenge for dermatologists. 

Results of a second study, published online in May in JAMA Dermatology, centered on Trichophyton indotineae – which is widespread in India and is now reported globally. First confirmed in the U.S. in 2023, the infection causes itchy and contagious rashes similar to those of TMVII, but it often resists terbinafine treatment, health officials said.

To better understand how T. indotineae can evade antifungal drugs, the researchers collected data from 11 men and women treated for ringworm in New York City hospitals between May 2022 and May 2023. Their ringworm was confirmed to have been caused by T. indotineae, health officials said. 

Seven of the patients received standard doses of terbinafine for anywhere from 14 days – which is the usual duration for most forms of ringworm – to 42 days, yet their rashes did not improve, according to a statement announcing the study.

When seven patients were treated with another antifungal called itraconazole, three recovered entirely and two improved, officials said. However, Caplan said the drug can interfere with many medications and can cause nausea, diarrhea, and other side effects that make it hard to use for long periods.

"These findings offer new insight into how some of the fungal skin infections spreading from South Asia can evade our go-to therapies," Caplan said in a statement. "Beyond learning to recognize their misleading signs, physicians will need to ensure their treatment addresses each patient’s quality of life needs."

This story was reported from Cincinnati. FOX News Digital contributed.