Two cases of highly contagious, drug-resistant ringworm infections have been detected in New York City – the first such cases reported in the United States, the Centers for Disease Control and Prevention reported on Thursday.

The infection was first identified in a 47-year-old woman who had developed a severe case of ringworm, also known as ringworm, while traveling in Bangladesh.

A rash had broken out over most of her body and the usual antifungal creams did nothing to alleviate it.

“My radar went up immediately,” said Dr. Avrom Caplan, an assistant professor of dermatology at NYU Grossman School of Medicine, who treated the patient and was one of the report’s authors.

The woman’s infection turned out to be caused by a relatively new species of ringworm-causing fungus, called Trichophyton indotineae. Over the past decade, infections with this drug-resistant fungus have spread rapidly in South Asia, likely fueled by the overuse of medications to treat them, including topical antifungals and corticosteroids, according to the CDC report.

The woman’s case prompted Caplan to ask his colleagues if they had seen similar infections. He soon discovered a second case in a 28-year-old New York woman.

That woman had developed ringworm over much of her body during the summer of 2021. In this case, however, the patient had not traveled outside of the US.

None of the women had underlying health conditions that could increase their risk of drug-resistant infections.

Caplan alerted public health officials to the two cases in February. Outside of Asia, cases have been identified in Europe and Canada.

Like drug-resistant bacteria, drug-resistant fungi are a serious public health problem. Cases of candida aurisAnother type of drug-resistant fungal infection has been spreading in healthcare settings across the US This infection is extremely difficult to treat and can be deadly.

«We always get so focused on antimicrobial resistance in relation to bacteria that we forget that those rules apply to fungi as well,» said Dr. Adam Friedman, professor and chair of dermatology in the College of Medicine and Sciences at George Washington University Health.

Friedman, who was not involved in the new report, said he has seen an increase in patients with fungal infections whose conditions take longer to respond to standard treatments or require additional medications.

«If you’re treating something with a drug that you hope will work, but you don’t get better, you have to go back to the drawing board,» he said.

What is ringworm and how is it treated?

Ringworm is not caused by a worm, as its name suggests. It is a fungal infection. It spreads easily through skin-to-skin contact and is usually seen as a circular pattern of raised, itchy scales. It can appear on the face, chest, scalp, or groin area. Ringworm can occur at any age, but it is most common in children.

Usually, cases are treated with antifungal creams. But some particularly difficult cases require antifungal medications, such as terbinafine or itraconazole, which are taken in pill form.

The two New York patients detailed in the CDC report were successfully treated with the oral medications. But medications, especially itraconazole, require a doctor’s attention. The drug can cause heart failure and should not be taken with certain medications, according to the National Library of Medicine.

Caplan said he suspects there may be other US cases of Trichophyton indotineae. The 47-year-old patient’s husband and son, for example, also developed ringworm and are undergoing tests to see if the fungi are the same.

At this point, however, he said, Trichophyton indotineae «not a widespread problem» in the US

Caplan suggested that people with suspected ringworm infections contact a dermatologist for an evaluation. He also recommended washing bedding, clothing, and towels regularly to minimize the spread of fungus.

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