Drug-resistant fungus spreads rapidly in hospitals across the U.S.

The Centers for Disease Control and Prevention (CDC) has identified Candida auris – a deadly and drug-resistant fungus – as an "urgent threat" due to its rapid spread in healthcare facilities across the United States. Cases have surged since its first U.S. appearance in 2016, with over 4,000 new clinical cases reported by March 2023. California recorded 1,566 infections during this same period, more than any other state.

Candida auris is a type of yeast that can cause severe infections, particularly in individuals with weakened immune systems. The fungus is notably resistant to multiple antifungal medications, complicating treatment efforts.

 "The rapid rise and geographic spread of cases is concerning and emphasizes the need for continued surveillance, expanded lab capacity, quicker diagnostic tests, and adherence to proven infection prevention and control," Dr. Meghan Lyman, a CDC epidemiologist, said.

The pathogen primarily spreads through direct contact with colonized or infected individuals, contaminated surfaces, and medical equipment. Patients with invasive medical devices – such as catheters or breathing tubes – face a heightened risk of infection. Symptoms can include fever, chills, sepsis, and organ failure. 

Indications now point to the fungus being active once more. 

According to a recent study, the rate of spread in Florida hospitals is concerning, and the Georgia Department of Public Health recently reported a spike in cases in healthcare institutions.

JoAnna Wagner from the Georgia Department of Public Health highlighted the challenge in disinfecting healthcare environments, stating, "many of the disinfectants that are EPA-registered and historically used by hospitals and medical facilities are not effective against C. auris."

Understanding the mechanisms behind Candida auris's drug resistance is crucial. Research indicates mutations in the ERG11 gene – which encodes the sterol-demethylase enzyme – contribute to fluconazole resistance. Additionally, overexpression of efflux pump genes can lead to multidrug resistance. 

Current treatment guidelines recommend echinocandins as the initial therapy for most patients. However, cases of echinocandin-resistant and pan-resistant infections are increasing. In such instances, investigational drugs may be considered. 

Emerging therapies are under investigation. Chinese researchers have developed Mandimycin, an experimental antibiotic that targets the lipid membrane of fungi, effectively killing drug-resistant strains like Candida auris in laboratory settings. 

Healthcare facilities are implementing stringent infection control measures to curb the spread of Candida auris. These include screening high-risk patients, isolating those infected or colonized, and employing specialized disinfectants, as common disinfectants may not eliminate the fungus, which can persist on surfaces for weeks. 

Ongoing research aims to develop more effective treatments and preventive strategies to combat this emerging public health threat.