Drug-resistant ringworm detected in US for first time, CDC says

For the first time, two cases of highly contagious drug-resistant ringworm infections have been detected in the United States, according to the Centers for Disease Control and Prevention. 

The CDC says the infections were found in two patients in New York City who did not improve with treatments. 

The first patient was a 28-year-old woman who developed a "widespread pruritic eruption" in the summer of 2021. The woman, who was pregnant at the time of diagnosis, had no known exposures to a person with a similar rash and no travel history. 

A second person, a 47-year-old woman, had developed a widespread pruritic eruption in the summer of 2022 while in Bangladesh. After returning to the U.S., she was prescribed multiple treatments without improvement. 

Both women required weeks of therapy to rid themselves of the infection. 

A New York City dermatologist notified public health officials of both patients who had severe tinea that did not improve with oral terbinafine treatment, raising concern for potential "Trichophyton indotineae" infection. Over the past decade, there has been an epidemic of severe, antifungal-resistant skin infection called tinea – commonly known as "ringworm" – in South Asia because of the rapid rise of T. indotineae. 

T. indotineae infections have been reported throughout Asia, Europe and Canada, but not the U.S. 

The CDC says the first patient’s lack of travel might suggest potential local U.S. transmission of T. indotineae. 

It urged health care providers that suspect T. indotineae infection to contact its corresponding state or local public health department for assistance with testing.