A dangerous and drug-resistant fungus, identified as Candida auris, can burrow into human hair follicles, alter the immune system, and establish a persistent presence on the skin, according to new research. This discovery sheds light on why the superbug can thrive on human skin for extended periods, making it a significant threat, particularly in healthcare settings.

Candida auris, first discovered in Japan in 2009 and detected in the U.S. in 2016, is a yeast that can enter the bloodstream and spread throughout the body. While typically transmitted in hospitals and nursing homes, where it can survive on surfaces for weeks, it poses a particular risk to individuals with weakened immune systems. For those with healthy immune defenses, the fungus often causes no serious illness and can remain undetected on the skin for months.

Researchers at the University of California, San Francisco, investigated the survival mechanisms of C. auris. In laboratory experiments using mice, they observed that while a common fungus, Candida albicans, was cleared by the immune system within days, C. auris persisted by taking refuge within hair follicles. This suggests hair follicles provide a sanctuary for the superbug.

Immune System Interaction

The study further revealed that C. auris manipulates the immune response. When encountering C. albicans, the immune system typically activates a response involving IL-17, which aids in skin repair and bolsters antifungal defenses. However, C. auris triggers a different immune signal, interferon gamma, which is usually associated with fighting viral infections. This diversion occurs as C. auris modifies its outer wall to expose chitin, a molecule that prompts nearby immune cells to release interferon gamma. This response hinders the skin's natural fungal defenses and slows the renewal of hair follicle cells, creating an environment conducive to C. auris multiplication.

"Chitin is widespread in nature, so it’s not like the human skin never encounters it, but we were surprised to see that C. auris actively uses its chitin to turn the skin into a perfect nest," said Dr. Suzanne Noble, a professor of microbiology at UCSF and co-senior author of the study.

Public Health Threat

C. auris has been designated an "urgent antimicrobial resistance threat" by the Centers for Disease Control and Prevention (CDC) due to its resistance to major antifungal medications. As of mid-July of 2026, approximately 3,000 cases of C. auris have been reported across 23 states, with Texas having the highest number of cases at over 700. New Jersey is among the states where cases have been confirmed.

The CDC estimates that up to 60% of individuals with C. auris infections may die, with the fungus contributing to roughly 3,000 U.S. deaths annually. While the exact fatality rate is difficult to ascertain due to underlying health conditions in infected patients, the fungus's ability to persist and resist treatment makes it a significant public health concern.

Experts note that effectively removing C. auris from the skin remains a challenge. However, the new findings on its interaction with hair follicles and the immune system could offer avenues for future therapeutic strategies. Current treatment often requires a combination of antifungal medications. Symptoms of infection, if they occur, can include fever, chills, fatigue, low blood pressure, and rapid heart rate, but many carriers remain asymptomatic.