A potentially deadly drug-resistant fungus has been spreading rapidly through US health care facilities, a new government study finds.

The fungus, a type of yeast called Candida auris or C. auris, can cause serious illness in people with weakened immune systems. The number of people diagnosed with infections, as well as the number of people found to have C. auris through screening tests, has increased at an alarming rate since it was first reported in the US, researchers from the Centers for Disease Control. and Prevention reported Monday.

The increases, «especially in more recent years, are really concerning to us,» said study lead author Dr. Meghan Lyman, medical director of the CDC Fungal Diseases Branchhe said in an interview. “We have seen increases not only in areas of continuous transmission, but also in new areas.”

Petri dish of candida auris in a laboratory in Wuerzburg, Germany
Petri dish of candida auris in a laboratory in Würzburg, Germany, 23 January 2018. Nicolas Armer/Image Alliance via Getty Images Archive

The new CDC warning, published in the Annals of Internal Medicine, comes as Mississippi is battling a growing outbreak of the fungus. Since November, at least 12 people have been infected with C. auris with four «potentially associated deaths,» according to the state health department, Tammy Yates, a spokeswoman for the Mississippi State Department of Health, said in an email.

There has been ongoing transmission at two long-term care facilities, although cases have been identified at several other facilities in the state.

«Unfortunately, multidrug-resistant organisms like C. auris have become more prevalent among our highest-risk individuals, such as residents of long-term care facilities,» Yates said.

The fungus can be found on the skin and throughout the body, according to the CDC. It is not a threat to healthy people, but above one third of people who get sick with C. auris die.

In the CDC report, the researchers analyzed data from state and local health departments on people sick with the fungus from 2016 through December 31, 2021, as well as those who were «colonized,» meaning they they weren’t sick but they carried it in their bodies. with the potential to pass it on to others who might be more vulnerable to it.

The number of infections increased by 59%, to 756, from 2019 to 2020 and then by a further 95%, to 1,471, in 2021.

The researchers also found that the incidence of people not infected with the fungus but colonized by it increased 21% in 2020 compared to 2019 and 209% in 2021, rising to 4,041 in 2021 compared to 1,310 in 2020. .

C. auris has now been detected in more than half the US states, the new study found.