Study finds C. auris contamination is high in northern Colombia health systems, indicating need for adherence to prevention and disinfection protocols.
Nancy A. Chow, PhD
Contamination of Candida auris, a multidrug-resistant yeast, is highly prevalent in the health care setting in the northern region of Colombia, according to a study in Clinical Infectious Diseases. The study emphasizes the importance of adherence to a strict infection control practice and disinfection strategy to avoid facilitating further outbreaks within health care systems.
“C. auris is an emerging yeast that can cause severe illness in hospitalized patients. It often does not respond to commonly used antifungal drugs and can spread between patients in hospitals and nursing homes, causing outbreaks,” study investigator Nancy A. Chow, PhD, told Contagion®. “We found that widespread contamination of C. auris can occur on surfaces in the hospital setting like the bed, equipment, sinks, and alcohol gel dispensers. This, along with colonization of patients, is facilitating its spread.”
A total of 4 hospitals in Colombia reporting a C. auris outbreak were enrolled in the study. Investigators took environmental and body swabs to examine the extent of the outbreak in each center. Additionally, investigators identified uninhabited patient rooms as well as rooms where patients had prolonged stays.
Surface samples were also analyzed, including patient beds and the adjacent environment, floors and items that sustained contact with the bed, any surface near the bed that was infrequently in contact with patients but was commonly in contact with the health care worker, as well as surfaces that had little contact with either patients or workers. Bathroom and hallway surfaces were also sampled. Researchers performed whole-genome sequencing (WGS) as well as antifungal susceptibility testing (AFST) on each isolate.
Approximately 41% (n = 7) of patients who were swabbed were found to be colonized with C. auris. In addition, the C. auris fungus was isolated in up to 12% (n = 37) of environmental samples collected in all surface zones. Areas where C. auris contamination were found included bed rails, a bed hand-controller, a cellular phone, floors, chairs, bed trays, medical equipment, closet cabinets, door handles, alcohol gel dispensers, sink basins, bedpans, and mop buckets. Modes of transmission, as discovered by WGS of 37 environmental surfaces and 15 colonized people, included a stretcher, bed mattress, and 2 healthcare workers. Additionally, C. auris was found contaminated on multiple floor surfaces, a non-disposable mop, and the sole of a healthcare worker’s shoe.
According to the WGS and AFST, C. auris-contaminated isolates in northern Colombia were more likely to be resistant to amphotericin B (AmB) compared with isolates from the central region of Colombia (P ≤.0001). Overall, up to 14% (n = 10) of isolates resisted fluconazole, whereas 31% (n = 27) resisted AmB. The investigators found a total of 4 novel non-synonymous mutations which were significantly associated with AmB resistance, including mutations of utg4_968953: T/C, utg5_821828: C/T, utg4_160118 (G/A), and utg4_352365 (G/A) single-nucleotide polymorphisms.
Findings from the study indicate the prevalence of C. auris contamination only, rather than reporting on the mechanisms of action or the strategies for preventing or treating the infection.
The investigators suggest a number of precautions for limiting the transmission of C. auris, including isolating the patient with C. auris in a single room, increasing hand hygiene on the contaminated unit or where the contaminated patient is receiving care, and disinfecting contaminated areas with an Environmental Protection Agency (EPA)-registered hospital-grade disinfectant that’s been proven effective against Clostridium difficile spores. In addition, routine daily and terminal cleaning and disinfection strategies of patient rooms is necessary in these situations to reduce transmission risk.
“We hope that these findings will raise awareness among clinicians and medical staff about the presence and persistence of C. auris in the health care environment and the critical importance of intensified infection control and disinfection strategies in controlling its spread,” concluded Dr. Chow.
For health care professionals, treatment and prevention guidance can be found at the US Centers for Disease Control and Prevention C. auris website: https://www.cdc.gov/fungal/candida-auris/index.html.