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Candida auris is the new superbug on the block you've probably never heard of. This stealthy,
drug-resistant yeast can already be found in hospitals worldwide, preying on those with
weakened immune systems. The fungus is so prolific that the CDC recently added it to
its list of urgent threats. So what exactly is candida auris and how did it fly under
the radar to emerge as a global health threat?
The feature of Candida auris is not so much the infection that it caused, but the fact
that it can spread.
And where did it come from? You know, where was it before 2009? That's the million dollar question.
Dr Zelazny is right. Candida auris kind of came out of nowhere. Unlike other fungi, this
yeast can only be found in people, which has scientists completely stumped. The very first case
of C. auris was confirmed when the fungus was isolated from the ear canal of a 70-year-old Japanese woman
as recently as 2009 and since then, it's spread rapidly across the globe.
Now, you may have heard of Candida, it's a term used for a genus of yeasts that are
responsible for the most common fungal infections worldwide. Most healthy adults, like you and
me, have a type of candida, called candida albicans, living all over our skin, as well
as within our throat and gut. This yeast usually doesn't do any harm, but given the right
conditions, it can flourish, and cause opportunistic infections; think athlete's foot, jock itch
and thrush. And those types of infections are usually treatable, but that's not the
case with C. auris.
Most candida auris are resistant to fluconazole, which is
a very common antifungal used to treat the candida albicans.
Another reason why C. auris poses such a threat is because its symptoms mimic other common
candida infections, making it incredibly difficult to diagnose in the first place.
Candida auris doesn't have any specific symptoms different from any other Candidas.
So it will be fever, if the patient has a sepsis or a blood infection. If the patient
has an urinary infection could be itching, going to the bathroom or can
be pain.
And since it can be easily confused with other yeast infections, special laboratory tests
are needed to specifically diagnose C. auris.
Only certain labs, like the NIH, that use more advanced technologies like MALDI-TOF
mass spectrometry or sequencing, could reliably identify Candida auris.
And identifying C. auris quickly is crucial since once the fungus enters the bloodstream,
it can be fatal, with a mortality rate between 30 and 60 percent. And that high mortality rate
is partly because C. auris preys on the sick. For reasons completely understood by researchers,
the fungus is able to spread rapidly in hospitals and nursing homes. It clings to everything
from medical equipment to beds, clothing, walls, ceilings, and even window shades, remaining
on surfaces for several weeks on end.
If you combine spreading from patient to patient, surviving in the hospital environment, even
after the patient left, and antifungal resistance, then you have a cocktail that could qualify
you as superbug.
Oh and if that's not scary enough, C. auris is also resistant to disinfectants. Hospitals
are now using specialized cleaning equipment and some have even been forced to take more
extreme measures like replacing floorboards and ceiling tiles to completely get rid of
the deadly fungus. And to try and stem the ongoing spread of C. auris, scientists are
scrambling to try and solve the mystery of its transmission.
Yeah, that's another question that people don't know yet. Skin seems to be the site
where it leaps. So perhaps transmissions through instrumentation.
And since its emergence on the world stage, there have been four types, or clades, of Candida auris
identified worldwide: from East Asia, South Asia, South Africa, and South America. So far, roughly
1,000 clinical cases of C. auris in the U.S have been confirmed, and knowing what we know
about C. Auris, that number is likely to go up.
Candida auris is emerging very quickly. So for those countries, or states within the
United States where it's prevalent, I would be concerned because you know when you
have transmission of an organism, you want to stop that cycle. You don't want this to continue.
Candida auris is new, so we need to make people more aware of it. And CDC is doing that along
the state labs. But I don't think everyone knows about it as much as they perhaps know
about superbugs, like super bacteria that are resistant to antibiotics.