More Drug-Resistant Fungi Are Growing From Excessive Antibiotic Use

Candida auris, a multidrug-resistant and highly transmissible fungus, is responsible for recent outbreaks in a few healthcare facilities in Washington D.C. and Texas.

Experts say that people who are healthy do not have to worry about contracting Candida auris. However, invasive fungi might grow more threatening and resistant to treatment because of excessive antibiotic use.

The yeast-like fungus has been discovered on rare occasions over the last few years. It was first identified in Japan in 2009 and more recently in New York City in 2019. In contrast to the current outbreaks, the 2019 cases were isolated within three patients and were not linked to transmission.

“This is different and worse because it's documented that the Candida auris can spread from person to person,” Adrian Popp, MD, chair of infection control at Huntington Hospital, tells Verywell.

“The good news is it’s still rare,” he says, adding that the infections mainly occur in people who have weaker immunity and the yeast is usually harmless for healthy individuals.

Candida auris spreads through contact and most commonly triggers a skin infection or skin colonization, but 5% to 10% of patients in the recent outbreaks have developed more invasive bloodstream infections.

Bradley (Brad) Perkins, MD, chief medical officer at Karius and former CDC executive, says that the more invasive cases typically result from another underlying disease or antibiotic resistance.

“All of this has been driven in the last couple of decades by antimicrobial resistance that is generally the result of a broad spectrum antibiotic use,” Perkins tells Verywell. “Doctors don't know exactly which organism is causing the infection, which is the upstream problem that results in these newly emerging organisms that have all this drug resistance.”

Drug resistance has been prevalent in other Candida species because of excessive antibiotic exposure. While Candida auris still responds to some therapies, practicing “antibiotic stewardship” is essential to preventing full treatment resistance, he adds. 

Antibiotic stewardship is the effort by healthcare providers to prescribe antibiotics responsibly to protect patients from dangers associated with “unnecessary antibiotic use” and antibiotic resistance, according to the CDC.

“There's concern that [Candida auris] has the potential to do what we've seen in other organisms, and that is to rapidly develop resistance to first, second, and third line therapy—and that's alarming,” Perkins says.

Antibiotic stewards must evaluate how antibiotics are used within animals and food supply as well as in humans, as all parts are connected, Perkins adds.

Perkins’ team at Karius focuses on identifying a patient’s specific infection, so that doctors are more informed on the correct treatment to use, before overusing antibiotics and creating drug resistance.

Rajesh Gandhi, MD, an infectious diseases physician at Massachusetts General Hospital and chair of the HIV Medicine Association, also stresses the importance of antibiotic stewardship, noting how some treatments for COVID-19 may have exacerbated levels of antibiotic resistance.

“Many hospitalized patients with COVID received broad-spectrum antibiotics even though the rate of bacterial superinfection, especially early in the course of COVID, is low,” Gandhi writes to Verywell. 

In August 2020, Candida auris was found in a Florida COVID-19 Unit. There doesn’t appear to be a connection between the COVID-19 virus and the Candida auris fungus, Perkins says, but COVID-19’s effect of weakening the immune system can make a person more vulnerable to other infections. He adds that the fungus “does not appear to be a community-based risk at this point.”

Staying out of the hospital unless necessary and getting vaccinated against COVID-19 are good ways to protect yourself from potential exposure to Candida auris, Perkins says. Likewise, hospitals should practice effective sanitation rituals and containment measures and use personal protective equipment.