Largest outbreaks of deadly mushrooms in the United States seen in southern Nevada

The Centers for Disease Control and Prevention has sounded the alarm over the growing threat posed by a drug-resistant and potentially deadly fungus that has sparked the nation’s largest outbreaks in hospitals and long-term care facilities across the south. of Nevada.

The Candida auris fungus has spread at an “alarming rate” in the United States, with a tripling of the number of cases resistant to the most recommended antifungal used to treat infections, the federal public health agency said on March 20. His data was included in a new study published the same day in the Annals of Internal Medicine.

Eradication of the fungus from places where it has taken hold is unlikely, the study’s lead author told the Review-Journal on Wednesday.

“It’s more difficult if you detect this situation after there’s already been undetected transmission for some time,” said study author and CDC epidemiologist Dr. Meghan Lyman.

This scenario played out in multiple places, she said, including southern Nevada. Last year, Nevada reported the most cases of any state, according to CDC data.

In April of last year, the Nevada Department of Health and Human Services alerted health care providers to fungal outbreaks in southern Nevada, as first reported in the Review-Journal. The first cases were identified in August 2021.

In 2022, Nevada reported 384 of the nation’s 2,377 clinical cases of C. auris, according to CDC data. At least 27 states and the District of Columbia have reported cases, with the first infections in the United States being reported in 2013.

Since August 2021, more than 1,000 people in southern Nevada have been infected with the fungus, according to data from the Nevada State Public Health Laboratory at the University of Nevada, Reno’s School of Medicine. There was only one case detected in northern Nevada, Reno in 2019. About 100 patients with C. auris have died, according to lab data.

Nearly 500, or nearly half, of Southern Nevada residents identified with the fungus had clinical cases, such as an invasive blood, heart, or brain infection. The others were colonization cases, in which the fungus was detected alive on the person’s skin but had not caused infection.

The fungus does not usually pose a threat to healthy people. Patients most at risk of infections are patients who have been hospitalized for long periods of time, with a central venous catheter – also called a central line – or other lines or tubes entering their body, or who have previously received antibiotics or antifungal medications, according to the CDC.

The fungus can be spread from colonized individuals who are unaware they have it. It can also spread from surfaces, such as a bed rail or equipment, where it can survive for long periods.

Not the new COVID

Candida auris is not considered by health authorities to be the next COVID-19, which has spread widely through ordinary activities and infected – and sometimes killed – previously healthy people.

David Hess, a genomics scientist with the state public health laboratory, said C. auris is more comparable to MRSA, a drug-resistant staph infection that’s also associated with healthcare settings.

In other words, it is a serious threat to public health. To better track the threat, the lab, after receiving notification about the outbreaks, started a year ago to perform whole genome sequencing, an advanced technique for genetic analysis, on samples from every positive test result. for C. auris.

Scientists in the lab have discovered that the fungus mutates in such a way as to make it resistant to the preferred antifungal drug to treat it, a development that the lab’s molecular supervisor, Andrew Gorzalski, described as alarming.

Only three classes of antifungal drugs are used, the scientists said. Most cases of C. auris are naturally resistant to one type, the azoles. A second type, polyenes, can cause fever and tremors in patients, earning it the unfortunate nickname “shake and bake.”

In 2-3% of cases, C. auris shows increased resistance to the preferred treatment, echinocandins, according to laboratory analysis.

“We’re seeing this resistance evolving in the Nevada outbreak where we haven’t seen it before, and it’s something we’re still getting our hands on,” Hess said.

Nevada performs the most real-time screening for fungal resistance of any state affected by an outbreak, he said. By quickly identifying drug-resistant cases, authorities can work with doctors and healthcare facilities to focus on stopping their spread.

“We think this will be one of the best strategies going forward,” Hess said.

CDC’s Lyman noted that new antifungals are being developed and that the federal government will consider licensing existing FDA-approved antifungals for other conditions to treat invasive cases of C. auris.

Trace the path of a pathogen

Thanks to its genetic analysis, the state laboratory was also able to trace the path of the fungus. He initially found three distinct clades or strains in southern Nevada. One quickly died out. The other two were distributed among medical institutions.

The other two strains were originally identified in cases at Sunrise Hospital and Medical Center and Centennial Hills Hospital Medical Center, Nevada Department of Health and Human Services spokeswoman Shannon Litz said last year.

Two additional strains have been identified more recently, including one from Texas. The analysis indicates that Nevada patients introduced strains to Arizona and Utah, Gorzalski said.

The fungus has been identified in more than 30 hospitals and long-term care facilities in southern Nevada, according to data from the Nevada Division of Public and Behavioral Health last year. The department did not provide the requested update on the data.

Candida auris is on the rise all over the country and around the world, not just in Nevada. “We had the biggest outbreak, it sort of took hold, but it’s something that shows everywhere,” Hess said.

To help stop transmission, the lab offers free, rapid tests to screen patients at high risk for C. auris, such as those admitted to a long-term care facility after being transferred from a hospital. Identifying a case on admission allows precautions to be taken before other people become infected.

Speaking generally of the cases in the United States, Lyman said, “I think there is certainly room for improvement with the identification of cases, either through clinical specimens or through testing. Often cases are identified late, or after they have been in a facility for some time, and have had the opportunity to spread to others.

She said there was also room for improving infection control practices in healthcare settings.

“A lot of health care and health service workers are working very hard at it, and it’s not easy to get good compliance and compliance,” she said.

Highlighting areas of improvement with Candida auris “will help for the next emerging pathogen, whether it’s a virus, bacteria or fungus,” she said. “Maybe by addressing Candida auris, we’re a little early for the next one.”

Contact Mary Hynes at [email protected] or 702-383-0336. Follow @MaryHynes1 on Twitter.