Dozens of people being treated for COVID-19 at a Florida hospital last summer became additionally infected with a mysterious, often deadly fungus called Candida auris, a US government study said Friday.

The multidrug-resistant yeast was first identified in Japan in 2009 and has been a top priority for the Centers for Disease Control and Prevention in recent years because of its increasing global spread.

C. auris is associated with up to 40 percent in-hospital mortality and is usually caught inside healthcare settings, especially when people have feeding or breathing tubes, or catheters placed in large veins.

It causes bloodstream, wound and ear infections and has also been found in urine and respiratory samples, but it’s not clear if the fungus actually infects the lung or bladder.

In July 2020, the Florida Department of Health was alerted to three Candida auris bloodstream infections and one urinary tract infection in four patients with coronavirus disease 2019 (COVID-19) who received care in the same dedicated COVID-19 unit of an acute care hospital (hospital A). C. auris is a multidrug-resistant yeast that can cause invasive infection. Its ability to colonize patients asymptomatically and persist on surfaces has contributed to previous C. auris outbreaks in health care settings.

Since the first C. auris case was identified in Florida in 2017, aggressive measures have been implemented to limit spread, including contact tracing and screening upon detection of a new case. Before the COVID-19 pandemic, hospital A conducted admission screening for C. auris and admitted colonized patients to a separate dedicated ward.

Hospital A’s COVID-19 unit spanned five wings on four floors, with 12–20 private, intensive care–capable rooms per wing. Only patients with positive test results for SARS-CoV-2, the virus that causes COVID-19, at the time of admission were admitted to this unit. After patient discharge, room turnover procedures included thorough cleaning of all surfaces and floor and ultraviolet disinfection. In response to the four clinical C. auris infections, unit-wide point prevalence surveys to identify additional hospitalized patients colonized with C. auris were conducted during August 4–18; patients on all four floors were screened sequentially and rescreened only if their initial result was indeterminate.

Hospital A’s infection prevention team, the Florida Department of Health, and CDC performed a joint investigation focused on infection prevention and control at hospital A that included observation of health care personnel (HCP) use of personal protective equipment (PPE), contact with and disinfection of shared medical equipment, hand hygiene, and supply storage. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.

Among 67 patients admitted to the COVID-19 unit and screened during point prevalence surveys, 35 (52%) received positive test results. Mean age of colonized patients was 69 years (range = 38–101 years) and 60% were male. Six (17%) colonized patients later had clinical cultures that grew C. auris. Among patients screened who had available medical records (20), two (10%) were admitted directly from a long-term care facility and eight (40%) died within 30 days of screening, but whether C. auris contributed to death is unknown.

HCP in the COVID-19 unit were observed wearing multiple layers of gowns and gloves during care of COVID-19 patients. HCP donned eye protection, an N95 respirator, a cloth isolation gown, gloves, a bouffant cap, and shoe covers on entry to the COVID-19 unit; these were worn during the entire shift. A second, disposable isolation gown and pair of gloves were donned before entering individual patient rooms, then doffed and discarded upon exit. Alcohol-based hand sanitizer was used on gloved hands after doffing outer gloves. HCP removed all PPE and performed hand hygiene before exiting the unit.

Investigators observed multiple opportunities for contamination of the base layer of gown and gloves during doffing and through direct contact with the patient care environment or potentially contaminated surfaces such as mobile computers. Mobile computers and medical equipment were not always disinfected between uses, medical supplies (e.g., oxygen tubing and gauze) were stored in open bins in hallways and accessed by HCP wearing the base PPE layer, and missed opportunities for performing hand hygiene were observed.

A combination of factors that included HCP using multiple gown and glove layers in the COVID-19 unit, extended use of the underlayer of PPE, lapses in cleaning and disinfection of shared medical equipment, and lapses in adherence to hand hygiene likely contributed to widespread C. auris transmission. After hospital A removed supplies from hallways, enhanced cleaning and disinfection practices, and ceased base PPE layer practices, no further C. auris transmission was detected on subsequent surveys.

The COVID-19 pandemic has prompted facilities to implement PPE conservation strategies during anticipated or existing shortages and to use PPE in ways that are not routine (e.g., extended wear and reuse).

Some health care facilities not experiencing shortages allow extra PPE layers because of the perception of increased protection for HCP. CDC does not recommend the use of more than one isolation gown or pair of gloves at a time when providing care to patients with suspected or confirmed SARS-CoV-2 infection.

Such practices among HCP might be motivated by fear of becoming infected with SARS-CoV-2 but instead might increase risks for self-contamination when doffing and for transmission of other pathogens among patients and exacerbate PPE supply shortages. When managing SARS-CoV-2 patients in a dedicated ward, HCP should maintain standard practices (e.g., hand hygiene at indicated times and recommended cleaning and disinfection) intended to prevent transmission of other pathogens. 

Outbreaks such as that described in this report highlight the importance of adhering to recommended infection control and PPE practices and continuing surveillance for novel pathogens like C. auris.

C. auris has now been documented in more than 30 countries, with some 1,500 US cases reported to the CDC as of October 31, 2020.

The CDC says the fungus can spread in healthcare settings “through contact with contaminated environmental surfaces or equipment, or from person to person.”