The first case of sexually transmitted ringworm was identified in the USA

Two rare genital ringworm infections are occurring in the United States, according to reports last month. This infection can potentially spread through sexual contact and may be resistant to standard antifungal medications.

A report published in JAMA Dermatology documented the first case in the United States in a man from New York City who had an infection caused by the fungus Trichophyton mentagrophytes Type VII (TMVII). The patient suffered from ringworm in the pubic and genital area, an area of ​​the body where such rashes do not often occur. Before he developed rashes, he traveled to England, Greece and California, where he had several male sexual partners.

Last year, researchers in France published a study of 13 men with TMVII, 12 of whom had sex with men. The authors said the fungus appeared to be spread through sex, as the lesions appeared in specific locations. In these cases, some patients may have acquired the infection locally, while others were likely exposed to TMVII after traveling to Southeast Asia and having contact with local sex workers.

“Fungal infections such as ringworm occur through any prolonged direct skin contact, but also via towels, bedding and clothing. Therefore, several factors must be ruled out before it can be determined that this case is solely due to sexual activity,” said Cadence Acquaviva, a spokeswoman for the New York City Department of Health.

Another study examined 11 patients with a related fungal strain called Trichophyton indotineae. Both fungi appear to spread primarily through close skin contact, and conventional antifungal treatments were ineffective in these patients.

Ringworm often presents as a circular rash. In these cases, however, the infection can resemble eczema lesions, making diagnosis difficult, said Avrom Caplan, MD, lead author of the study and assistant professor of dermatology at NYU Grossman School of Medicine.

So far, there have been only a few confirmed cases of these fungal infections. The goal of publishing these reports, Caplan told Verywell, “is not to alarm anyone, but primarily to alert clinicians that if someone comes in with these scaly or inflamed or itchy or painful lesions in the pubic or genital area, they should remember to think about (these fungi).”

What Trichophyton Infections look like

T. indotineae was identified primarily in India and Bangladesh but is now spreading worldwide. The first two confirmed cases in the U.S. were reported in New York state last year, but Caplan said earlier cases likely went unnoticed.

The lesions caused by this fungus usually spread over the face, body and groin area. They are often itchy and very inflamed.

Many people may be Trichophyton Fungi and do not develop infection. Typically, immunocompromised patients are most at risk for ringworm. However, Caplan said most of the patients in his study were immunocompetent but had a lot of ringworm.

“It can be confused with eczema, psoriasis or other skin conditions, which is why patients sometimes experience delays in getting the correct diagnosis,” he added.

It is unusual for a dermatophyte – a fungus that causes infections in the skin and nails – to spread through sexual contact, explained Mahmoud Ghannoum, PhD, professor and director of the Center for Medical Mycology at Case Western Reserve University and one of the authors of another case study on the possible sexual transmission of T. indotineae. Mushroom species such as Candidawhich often lives in the vagina, can spread through skin contact but does not usually cause a skin infection, he said.

Challenges in treatment

Scientists at the New York City Department of Health’s Wadsworth Center mycology laboratory analyzed the fungi’s genetic information and tested how they respond to different treatments.

TMVII, T. indotineaeand other superficial fungal infections can look very similar and can only be distinguished by advanced testing, such as DNA analysis.

The New York and European studies showed that people with TMVII could be treated with terbinafine, the common oral antifungal drug. These patients had to take the drug longer than most people with ringworm, but the infections eventually went away.

T. indotineae, On the other hand, terbinafine appears to be resistant even when taken for more than six weeks. In most patients, the infection could be treated with another oral antifungal. However, this treatment has significant drawbacks, such as interactions with other medications and side effects such as nausea and diarrhea, which is why it is not a good option for some people.

“(Terbinafine) is a drug that has been very good because we hardly saw any resistance to it. And now, lo and behold, we see resistance,” Ghannoum said. “This is a big problem because people talk about bacterial resistance, but we don’t have many infections that are resistant to fungal infections.”

Tests are key to detection and treatment Trichophyton Infections

If a patient has rashes that look like ringworm, the doctor may take a sample of the infection and send it to a laboratory for analysis.

“For example, if you look at a nail and think there is a fungal infection, there are many other diseases like cancer or bacterial infections that look like fungi, so you don’t know if it’s fungal or not. The only way to find out is to get a test,” Ghannoum said.

Diagnosing the pathogen using a laboratory test is crucial for the correct treatment. The laboratory tests how well different medications neutralize the fungal species.

TMVII and T. indotineae do not respond well to standard antifungals, which may be due in part to the increasing resistance to antifungals worldwide. This is similar to the antibacterial resistance that occurs when overuse and misuse of antibiotics allows the development of “superbugs” that are immune to existing drugs.

“We’re seeing some fungi that are what we call ‘pan-resistant’ fungi, which means they’re resistant to all available antifungals. That’s why we need more (antifungals),” he said. “But at the same time, we also need to do testing with what we have. Of the four different classes we have, one of them might work, but without testing, how do you know which one?”

If you are getting tested for a Trichophyton If you have an infection, Ghannoum says you should “insist” that your doctor send you a sample for laboratory analysis to ensure you receive the correct treatment.

The Centers for Disease Control and Prevention (CDC) is conducting a survey to find out how many cases of Trichophyton Infections are occurring in the United States. However, there is currently no evidence that the two new fungal infections are widespread, Caplan said.

If you have widespread rashes that look like ringworm, especially if you have inflamed or painful rashes in the genital or pubic area, you should consider being examined by a doctor, he said.

“There really shouldn’t be any shame or fear in reaching out to a doctor and saying, ‘I have this rash or sore that just won’t get better. Can someone take a look at it?'” Caplan said.