Drug-resistant ringworm spreads to 29 countries, study finds
A drug-resistant strain of ringworm has spread to 29 countries, with reported cases tripling between 2022 and the end of 2025, according to a study published in the medical journal Emerging Infectious Diseases. The first U.S. case was reported in 2023.
The strain does not respond to terbinafine, the antifungal medication most often used to treat ringworm either as a cream or a pill. That resistance allows infections to persist for months and makes treatment more difficult.
Ringworm is a common fungal infection that causes an itchy, scaly, circular rash. The same group of fungi can cause athlete’s foot. The infection spreads through skin-to-skin contact and through contaminated items such as towels, clothing, bedding and hairbrushes.
Most documented cases of the drug-resistant strain have been detected in Europe. Researchers said that pattern likely reflects stronger surveillance and laboratory testing rather than a higher rate of infection.
The report noted that cases are likely being undercounted in parts of Africa, India and the Middle East, where the fungus is already known to be common. Researchers said limited access to advanced testing and tracking tools may be preventing health officials from fully measuring its spread.
Researchers analyzed data from March 2022 through the end of 2025.
