Health experts are warning of new and highly contagious fungal strains after an NYC man in his 30s developed a sexually transmitted form of ringworm — the first reported case in the US.

“Healthcare providers should be aware that Trichophyton mentagrophytes type VII [TMVII] is the latest in a group of severe skin infections to have now reached the United States,” said Dr. Avrom S. Caplan, an assistant professor in NYU Grossman School of Medicine’s dermatology department.

Caplan co-authored a case study published Wednesday about an unidentified New Yorker who became infected with TMVII, with a rash appearing on his penis, buttocks and limbs. Cases of TMVII have been on the rise in Europe, especially in men who have sex with men.

The man in the new case study had visited England, Greece and California. He reported having sex with men during his travels, none of whom disclosed similar skin issues.

“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,” study senior author Dr. John G. Zampella advised.