There is a new contagion catching the nation’s attention, a fungus turning people into zombies.
It’s the plot of HBO’s “The Last of Us.”
But there is another story about fungi and it’s causing real-life concerns. A new study by federal scientists has found a potentially dangerous fungus detected in Maryland and three other states in 2016 has spread to more than half the country.
The number of infections in humans by Candida auris, or C. auris, is far lower than depicted on the television show, and nowhere near the number of serious COVID-19 infections still being counted. This germ, however, is more sophisticated than any virus, and able to adapt to a warming global climate, resist treatment and spread rapidly.
“For the majority of people, this is not an immediate threat; this is not ‘The Last of Us,’” said Dr. Arturo Casadevall, a fungal disease expert and professor of molecular microbiology and immunology in the Johns Hopkins’ Bloomberg School of Public Health.
“It is an ongoing problem for hospitals and long-term care facilities with debilitated individuals and very consequential for individuals because it has high mortality,” he said. “And the fear is, long-term, things change and this could spread outside of hospitals and become a community-acquired infection.”
In general, fungi are an important part of life, helping break down dead and decaying organic matter, he said. They also are food (think mushrooms) and used in making food and beverages (yeast is used to make wine and beer). Fungi also are used to make medicines, including penicillin and other antibiotics.
Most healthy people with an infection by common fungi may be more annoyed than harmed. Fungi cause toenail and vaginal yeast infections. But C. auris can be deadly, particularly for those infected while undergoing chemotherapy, an organ transplant or HIV therapy.
Fungi can spread rapidly in someone’s lungs and organs and be hard to clear, said Casadevall, author of a forthcoming Hopkins Press book with Stephanie Desmon on the kingdom of fungi.
It’s the rate of C. auris spread around the country that struck scientists from the U.S. Centers for Disease Control and Prevention. They reported in the March edition of the journal Annals of Internal Medicine that cases nearly doubled from 2020 to 2021.
Further, the number of infections resistant to the most recommended antifungal treatment, known as echinocandins, tripled.
“The rapid rise and geographic spread of cases is concerning and emphasizes the need for continued surveillance, expanded lab capacity, quicker diagnostic tests and adherence to proven infection prevention and control,” said Dr. Meghan Lyman, a CDC epidemiologist and lead author of the paper, in a statement at the time of the report’s release.
Data shows the nation had 5,514 cases in 2021 where a patient was infected or carrying the fungus. While data in the paper ended in 2021, a map on the CDC site showed the number continued to rise and reached 8,151 in 2022.
The paper said cases may be rising because of poor infection control, but also because health authorities are testing for it more. Scientists also cited strain on the health care system during the coronavirus pandemic as another cause for the increase.
More cases are likely to be detected as the CDC expands testing from 7 to 26 labs nationwide.
Last October, the World Health Organization listed C. auris among 19 fungal “priority pathogens” threatening public health. The global body called for more attention, resources and surveillance, as the total number of infections is likely to grow with development of more invasive forms.
In Maryland in 2022, there were 46 cases where patients were sickened by the fungus, up from 29 the year before. So far this year there have been 17 cases, which would put the state on pace to exceed the prior year’s total. Of the total cases this year and last, 13 people died within 30 days of diagnosis. All had underlying medical conditions, and state health officials said it was difficult to determine the exact cause of death.
“Cases have been identified in all regions of Maryland,” said David McCallister, a state health department spokesman. “In response to cases of C. auris, [the Maryland Department of Health] and the local health departments work together with Maryland health care facilities in accordance with CDC guidance to ensure that healthcare workers caring for C. auris-positive patients are taking steps to prevent transmission to other patients.”
The CDC guidance calls for frequent hand washing, use of gowns and gloves, and cleaning of equipment and patient rooms, as the fungus can spread from person to person and from surfaces and airborne spores.
Casadevall said the fungus can be tough to clean, and some facilities may not be immediately aware a patient has an infection. Symptoms develop over time, and include fever, chills, sweats and low blood pressure.
“Once a hospital knows it has it, it’s an infection control problem,” he said. “Patients need to be isolated and they need to clean everything, though it’s quite resistant to cleaning. It gets on bed rails and in walls, and you can’t just wipe it down with alcohol. It requires a bit of work.”
If the infections can’t be prevented, some researchers say perhaps they can be better treated.
Jeffrey Gardner, an associate professor of biological sciences at the University of Maryland, Baltimore County, won a $1.3 million grant from the National Institutes of Health to develop new antifungal treatments that don’t lose their effectiveness, as current therapies are prone to doing.
He’s investigating thousands of bacterial enzymes to find the three or four displaying antifungal properties. He’ll then engineer them to attack the walls of cells that make up certain fungi. Current antifungals attack development of those walls, which are composed of a sugary substance, by interfering in their production. But unfortunately, that’s the part that fungi are good at circumventing.
Down the road — likely years — other scientists can turn the battle-ready enzymes into medicines to use alone or with existing treatments.
“It could be used as a wound dressing or applied to catheters or ventilators,” he said, “or as a fluid used in a patient.”
That may be the firepower that doctors, and perhaps “The Last of Us,” are looking for.