Two highly contagious ringworm strains that defy standard treatments are arriving in the United States, according to a new report by NYU Langone Health, a medical center chain in New York City.
New Strains Are Harder to Diagnose
The NYU Langone Health report references two case studies.Doctors Should Be Vigilant: Researchers
Although rates of TMVII and T. indotineae infections are currently low in the United States, the researchers urge health care providers to be vigilant for signs and symptoms, especially in sexually active patients, recent travelers, or those with unexplained itchy rashes.“Healthcare providers should be aware that Trichophyton mentagrophytes type VII is the latest severe skin infection to reach the United States,” Dr. Avrom Caplan, an assistant professor in the Department of Dermatology at NYU Grossman School of Medicine, said in a press release, urging providers to ask about groin and buttocks rashes in at-risk patients directly. His team is expanding research efforts to track emerging cases.
US Cases First Reported in 2023
According to the new report, the first T. indotineae infections in the United States were reported in March 2023, when Dr. Caplan sent samples from two ringworm infections to a New York state public health laboratory. The lab used genomic sequencing, a method used to determine the entire genetic makeup of a cell, to identify the isolates as T. indotineae.The cases were initially detected in New York in 2021 and 2022 and involved two women. One had recently traveled to Bangladesh, while the other woman had no travel history to explain how she became infected, suggesting the disease was already present in the United States.
Crop Fungicides Fueling Severe Fungal Infection Outbreak: Doctor
An epidemic of severe, antifungal-resistant tinea (fungal skin infections) originated in South Asia due to the rapid spread of the treatment-resistant strain T. indotineae, then spread over the past 10 years, according to the CDC. The problem is likely driven by the misuse and overuse of topical antifungals and corticosteroids.“Farmers use fungicides to combat these, but this can lead to resistance in human-infecting fungi due to shared molecular targets between fungicides and antifungal drugs,” Dr. Ng said.
Developing new antifungals is challenging due to the genetic similarities between fungi and humans, making it difficult to target fungi without harming human cells, he noted.
Fungi develop drug resistance quickly, and only three major classes of antifungal drugs exist compared to dozens of antibacterial classes. “We urge providers to continue to practice antimicrobial stewardship in order to slow down the spread of multi-drug-resistant infections,” Dr. Ng said.