W What is known about the fungus Candida auris confuses the scientists who study it, the doctors who are struggling with the treatment of the persistent infections that it causes, and the infection control teams that make an effort to find it To remove infected patients from the hospital.
But the list of unknowns about this highly unusual mushroom is even longer – and fascinating. Experts say there is an urgent need for answers and funding to generate them.
Candida auris was first discovered in Japan a decade ago and has recently appeared in remote parts of the world. The fungus does not behave like a fungus. It causes outbreaks like a bacterium and is generally very resistant to available antifungals. It is a growing and profound problem.
Recently, STAT has asked a number of scientists to describe what they consider to be the most pressing research questions in the field. Here are her thoughts:
Where does the damn thing come from?
Most mushrooms ̵
It must be somewhere else in nature, said Tom Chiller, head of the Department of mycotic (ie fungal) diseases in the Centers for Disease Control and Prevention.  "They are not just" sucker "appeared," Chiller insisted. "You've been here for a while, and I wonder where they hid."
Tejas Bouklas, assistant professor at Long Island University's Department of Biomedical Sciences, Campus Post, wants to know which other species infect C. auris
Knowledge Where the fungus lives in nature and how humans absorb it may help to answer another very urgent question.
Why and how are different clones of the fungus in a very short time
Several years after their discovery in 2009, several countries around the world reported cases of C. auris, originally thought to be responsible for the movement by travelers or medical tourists However, genetic sequences showed that this was not the case.
Samples of C. auris circulating in South Africa all looked very similar the samples from Asia and South America. But none of them looked like the other one. And they do not always behave like each other.
Chiller found that the cases of C. auris reported in Japan appeared to be primarily ear infections – the original finding of the fungus was from an ear infection, hence the "auris" of the name. In Japan, the fungus does not seem to cause invasive diseases. it does not get into the bloodstream But in South Korea, it does the same clone (thought-strain) of C. auris.
"Would not it be fascinating to know which changes in this organism make it from an infection of the outer ear to an intruder?" Chiller considered. "Is there something that changes in the genome? … I wish people would just jump on it and study it. "
Knowing how and why is crucial, Dr. Luis Ostrosky, Professor of Infectious Diseases at McGovern Medical School, University of Texas Health Science Center, Houston.
That's "the only way we can control it. Because if we do not know the source, we'll fight the fire a bit, "said Ostrosky, director of the Mycological Research Laboratory at his hospital. "If you do not know the source of an infection, you can never fully control it, and it will continue."
The near simultaneous onset of a highly drug-resistant fungus that acts like a bacterium, it seems … well, somehow disconcerting, what has happened so that this Candida species works in a way that candida fungi normally do not work?
A related concern: when this fungus has learned this trick, Is it what the future holds?
A recent study published in the journal mBio suggests that climate change may have contributed to the emergence of C. auris, the authors say that in the past, body temperature In fact, we are too hot for them to grow well in us, but when the globe has warmed, ha they are adapted.
If the theory is correct, other fungi can follow the path of C. auris, Arturo Casadevall of the Johns Hopkins Bloomberg School of Public Health, and his co-authors.
"Whether C. auris is the first example of new pathogenic fungi resulting from climate change … its emanation fuels the concern that humanity may be facing new diseases resulting from the adaptation of fungi to hotter ones Climate zones, "they write.
The background story of Auris is important. "These things will continue to appear. And if we understand how they emerge and where they arise, we could develop prevention strategies or reactive strategies or preparation strategies for the next big thing. "
Could C. auris help other mushrooms adapt to major human threats?
That's a question that Bouklas wonders. "The more ubiquitous it gets, the more problematic it becomes. Because now it might be able to transfer DNA to other Candida species. And maybe even bacteria, "she said.
This idea is not far-fetched. Mushrooms mate sexually, Chiller emphasized, allowing them to exchange large amounts of DNA.
Where did he get his "Ironman Suit" from?
Thus, Johanna Rhodes describes the drug resistance superpowers of C. Auris. Rhodes is an epidemiologist at Imperial College London who has been working on C. auris since 2016 at Royal Brompton Hospital in London.
Some of the patients in this outbreak developed within a month of resistance to a whole class of antifungals is simply unheard of, "she said.
Also Bouklas has resistance issues. "Why does it have such a strong resistance to all known antifungals?" She asked. "All of them use a different killing mechanism …. That's the biggest question.
Often, pathogens that develop drug resistance pay for it in other ways – this is referred to as "fitness costs." Yes, Bacteria X can dodge Drug Y, but when it acquires this ability, it becomes less transmissible or weaker in some ways.
Not C. auris.
"It seems that there is resistance without fitness costs. It can still form biofilms. It can still exist [in an environment]. It can still infect, "said Rhodes.
Biofilms are a layer of pathogens – in this case fungi – that attach themselves to a surface and are effectively lying in wait there. Sometimes biofilms form in the drains or pipes of sinks in hospitals. Many like wet surfaces, but C. auris can form dry biofilms that lurk on surfaces such as bed rails in contaminated hospital rooms. These infectious residues can be transmitted from patient to patient in a hospital room.
This fungus is really hard to get rid of. That's something Dr. Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases, considers it necessary.
"Why is it so different from others that you could easily wipe it off by wiping it with whatever it is with, does it go away? While this just seems to stay here, "Fauci asked.
Ostrosky also wants to know why the fungus spreads so well in hospitals that are not usually terribly hospitable to mushrooms.
What is the best treatment method? Patients who develop C. auris infections?
This is a question that Ostrosky, who treated patients with C. auris infections, would like to have answered.
Chiller has a related question: how often is C. auris cause of death?
The CDC estimates that between 30% and 60% of patients die from C. auris infections. But in the United States, infections with C. auris occur in sick patients anyway: people with weakened immune systems who have spent a long time with ventilators – machines that breathe for people whose lungs are not up to the task.
Do these people die from their C. auris infections? Or are your other medical problems the cause of death? "Do they die of C. auris or C. auris? I still want to know that, "Chiller said, but acknowledged that" these are really difficult studies ".
– In an earlier version of this article, the name of Luis Ostrosky was misspelled.