A rare and highly contagious sexually transmitted fungal infection that has been on the rise in Europe has made its U.S. debut with a confirmed case in NYC.

An unidentified man in his 30s developed a fungal skin infection after returning home to NYC from a trip to England, Greece, and California. The man developed symptoms of skin rashes from tinea (ringworm) on his penis, buttocks, and limbs, according to a case study published in Jama Dermatology.

Genetic testing on skin lesions identified the fungal infection as Trichophyton mentagrophytes type VII (TMVII), a sexually transmitted form of ringworm. This strain has been increasingly reported in Europe, with 13 cases in France last year, primarily among men who have sex with men.

The patient mentioned in the case study reportedly had sex with multiple male partners during his travels. However, none of them had similar skin issues.

The patient's Trichophyton mentagrophytes type VII infection responded to standard antifungal treatment but required four and a half months to heal completely. Health experts caution that this infection can take months to resolve, even with treatment.

"Healthcare providers should be aware that Trichophyton mentagrophytes type VII is the latest in a group of severe skin infections to have now reached the United States," study lead author, Dr. Avrom Caplan from the NYU Grossman School of Medicine, said in a news release.

However, experts assure that there is no cause for alarm among the general public, as there is no evidence that the infection is widespread.

"There's no evidence that this is widespread, or that this is something that people really need to be worried about. But if people are having itchy eruptions in areas like the groin, and it's not getting better, see a doctor," Dr. Caplan said.

Since the sexual partners of the infected patient had no signs of ringworm infection, Dr. Caplan did not rule out the possibility that the patient contracted it from a sauna he visited two months before developing symptoms.

Sometimes the rash can be misdiagnosed as eczema because it lacks the typical circular lesions seen in ringworm cases, potentially delaying diagnosis in affected individuals, Dr. Caplan said.

"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," said senior author Dr. John Zampella.