Why is the deadly fungus Candida Auris spreading so fast in the US?

In something seemingly straight out of an episode of The last of usa dangerous fungal infection has been spreading across the country.

The US Centers for Disease Control and Prevention announced in a new study published in the journal Annals of Internal Medicine than the fungus candida auris is spreading more and more throughout the United States, with 17 states identifying its first C. auris case between 2019 and 2021.

There was a 44% increase in cases observed between 2018 and 2019, which skyrocketed to a 95% increase in cases between 2020 and 2021, from 756 cases in 2020 to 1,471 cases in 2021. In 2022, it is believed to have There have been 2,377 cases of infection in the United States.

This fungal infection is also resistant to a number of antifungal medications and therefore poses a “serious threat to global health,” according to the CDC.

candida auris it is a yeast that usually does not cause symptoms, but can cause blood infections, wound infections, and ear infections in patients with weakened immune systems and those with lines and tubes that go into the body.

Stock illustration of a Candida auris structure. This fungal infection has seen an increase in cases in the United States, according to new data from the CDC.iStock/Getty Images More

People most at risk are people who are immunocompromised, those who have recently had surgery, and those who have some form of diabetes or have recently used broad-spectrum antibiotics and antifungals. The infection most often affects people in hospitals, killing one in four infected patients.

“Infections by C. aurissometimes called fungemia, has been reported in 30 or more countries, including the United States,” said Rodney Rohde, Regents Professor of Clinical Laboratory Sciences at Texas State University. news week. “They are often found in blood, urine, sputum, ear discharge, cerebrospinal fluid, and soft tissue, and occur in people of all ages.

“According to the US Centers for Disease Control, the mortality rate in the US has been reported to be between 30 and 60 percent in many patients who had other serious illnesses,” he said. “In a 2018 summary of the research to date on the global spread of the fungus, researchers estimated mortality rates of 30 to 70 percent in C. auris outbreaks among critically ill patients in intensive care”.

The reasons for the increase in cases in the US are likely due to transmission in a hospital setting and the difficulty in detecting this type of infection.

C. auris it is shed in the hospital setting and can persist in patients and equipment,” said Daniel Henk, a fungal specialist and professor of microbial ecology at the University of Bath in England. news week. “I think one outbreak in a UK setting was linked to reusable underarm thermometers. That subsequent transmission is the highlight of C. auris me and probably most other mycologists.”

Environmental surfaces and medical devices are common ways infection is spread, especially to people with weaker immune systems.

Stock image of Candida species under the microscope. According to the CDC, the mortality rate in the US for Candida auris cases has been reported to range from 30 to 60 percent in many patients with other serious illnesses.iStock/Getty Images More

“One of the key mechanisms for this to occur is the formation of biofilms,” Rohde said. “Overall, general infection prevention and control (IPC) malpractices in healthcare settings can be part of the equation.

“It is possible that during the COVID-19 pandemic, IPC practices became less important, especially on the environmental surface aspect, than during non-pandemic times. Another reason could be increased surveillance/testing of people who have been detected as colonized but not infected with C. auris.

C. auris It was discovered about a decade ago and only recently began to spread around the world.

“It wasn’t really known until about 10 years ago (it was first described in 2009, but didn’t get a lot of attention until after 2013). The first reports of infection are more like, ‘hey, this new fungus is causing some infections and we don’t know if it’s really bad or not,'” Henk said. “So, unlike yeasts that have been living with us for a long time and causing all kinds of diseases that we’re familiar with, C. auris it’s new for hospitals and clinics and also for mycologists.”

Other types of yeast infections are often due to other Candida species, particularly Candida albicansthat cause infections of the mouth, skin, and vagina.

The main concerns that the CDC has listed are that C. auris it often occurs in a healthcare setting with hospitalized patients who are already frail, and is often misidentified as another condition due to difficulty of detection. In addition, the fungus is often resistant to antifungal drugs, with almost all samples tested from C. auris having been found to be resistant to at least one class of antifungal drug.

“Even more alarming was the tripling in 2021 of the number of cases resistant to echinocandins, the most widely recommended antifungal drug for the treatment of C. auris infections,” Rohde said. “The CDC has considered C. auris as an urgent antimicrobial resistance [AMR] It is a threat because it is often resistant to multiple antifungal drugs, spreads easily in health care settings, and can cause serious infections with high mortality rates.”

In addition to increasing cases in the US, the number of cases has also spread across 30 countries.

“Global spread is still early enough that mycologists have been able to identify lineages as they move, sort of like in SARS-Cov-2,” Henk said. “I am most familiar with the UK, where there has definitely been an increase in outbreaks since it was first reported. Of course, when something is new, it’s hard to go in any direction but up. So far, the Most have been contained here, but it is a matter of time.”

So what can we do to stop the spread of this strange and deadly fungal infection?

“Everyone should use proper hand hygiene with soap and warm water or alcohol-based hand rubs,” Rohde said. “Healthcare professionals and similar caregivers should also use appropriate PPE, such as gloves and gowns. There is also an urgent need for robust diagnostics for accurate identification in public health and medical laboratory, laboratory management, antimicrobial administration , real-time AMR surveillance, and support for antifungal discovery alongside antibiotics and other antimicrobial drug classes.”

Preventing transmission within and between hospitals will likely need several things in place, Henk explained.

“Probably the most important thing is really improved diagnosis and monitoring that can alert staff early to potential outbreaks,” Henk said. “The lack of awareness and regular monitoring means that once people find out, it’s often too late to manage effectively.”

It is possible that the effects of climate change will further increase the spread of this fungus in the coming years.

“Some researchers have estimated that climate change and other similar factors [encroachment into non-human habitat] may be leading to increases globally. C. auris as an urgent threat in the United States, or the WHO list of priority fungal pathogens that identifies c. auris as a global priority,” Rohde said.

This isn’t the only fungal disease that may be made worse by climate change: frogs around the world are being wiped out by a fungal skin infection known as chytridiomycosis, which may be more effective at spreading due to climate change. In addition, the human fungal disease “Valley Fever,” usually only contracted in the southwestern US states, has spread across the country, a change believed to have occurred due to weather pattern disturbances. caused by climate change.

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