A new report by the Centers for Disease Control and Prevention (CDC) warns that an emerging fungus, Candida auris, is spreading rapidly in U.S. healthcare facilities. The CDC has labeled the fungus as an urgent threat due to its resistance to multiple antifungal drugs and its ability to cause severe infections with high death rates.
According to national surveillance data published in the Annals of Internal Medicine, the number of clinical cases has increased annually since 2016, with the most significant rise between 2020 and 2021. Cases of active C. auris infection rose from less than 500 in 2019 to almost 1,500 in 2021, and screening cases, where the fungus is detected but not causing infection, tripled from 2020 to 2021, totaling more than 4,000. The CDC reports that case counts for 2022 also climbed, although final numbers are not yet available.
- auris has been detected in over half of all states, and 17 states reported their first C. auris case between 2019 and 2021. The fungus was first identified in Japan in 2009 and is named after where it was first discovered in the body, as “auris” is Latin for ear. It has caused outbreaks in healthcare facilities and nursing homes and can spread through contact with affected patients and contaminated surfaces or equipment.
The CDC estimates that once a C. auris infection becomes invasive, one in three patients will die. The most vulnerable individuals are those who are already seriously ill, such as patients on ventilators, those with invasive medical devices, those who have had previous treatments with antibiotics or antifungal medication, and those with long or frequent healthcare stays.
The general population is not at risk, but people can carry the fungus on their skin without causing infection, which can then be passed on to others.
- auris is hardy and can survive on surfaces for several weeks, making it even more likely to spread. Climate change may be a factor in its ability to survive, as it appears to be more tolerant of higher temperatures.
The antifungal medicines commonly used to treat similar types of infections often don’t work for C. auris, which is particularly concerning to public health officials. The latest study shows that the number of cases resistant to echinocandins, the antifungal medicine most recommended for C. auris infections, tripled in 2021 over the previous year. Fungus and bacteria seem to be quickly evolving to resist existing treatments, outracing the development of new antibiotics and antifungals.
The increasing number of cases and transmission of C. auris is concerning and highlights the need for improved detection of cases and infection control to prevent spread. Screening is essential to prevent transmission, and patients carrying the fungus need to be identified so that infection prevention controls can be used. Good hand hygiene and cleaning can also help prevent transmission. Improved prevention measures will help with the next emerging threat.