Healthcare Hygiene magazine October 2019 | Page 15

cover story
Candida auris: A Stealth Enemy
With Environmental Persistence
By Kelly M. Pyrek
P
ublic health entities such as the Centers for Disease
Control and Prevention (CDC) and the World Health
Organization (WHO) have compiled lists of the problem
pathogens that continue to represent some of the greatest
challenges to infection prevention and control (IPC) efforts.
Rising on that list is Candida auris, an emerging worldwide
public health scourge that is growing in intensity as a
healthcare-acquired organism. It is particularly fearsome
because of its innate resistance to multiple anti-fungal drugs
and its resilience in the face of traditional hygiene measures.
In contrast to other Candida species, C. auris is transmit-
ted easily in the healthcare setting, and it is demonstrating
the ability to persist both in the human host and on
inanimate surfaces.
“Candida auris is an emerging fungus and one of the
headaches with this species is it’s multidrug-resistant, mean-
ing that it is resistant to multiple antifungal drugs commonly
used to treat Candida infections,” confirms Rodney E. Rohde,
PhD, MS, professor and chair of the Clinical Laboratory
Science Program at Texas State University.
C. auris is also transcending traditional classification.
“Infection prevention experts tend to want to assemble
pathogens into groups such as healthcare-acquired or com-
munity-acquired, but when it comes to resistant organisms
you really can’t use those terms anymore,” Rohde says.
“For instance, in some of the studies I have conducted with
different organisms, what we used to think was only in the
community, we see those strains or genotypes showing
up in healthcare patients, and vice versa. So, even though
microbiology and science tells us certain species are strictly
found in the healthcare setting or strictly found in the
community setting, in reality, it’s more of a global presence
now due to so many vehicles and vectors that move in and
out of healthcare settings.”
Rohde continues, “When we talk healthcare settings, we
tend to only think hospitals, but we must think long-term
care, outpatient and dialysis centers, clinics, and school
and university health centers. I think it’s a communication
problem; as scientists, we love to put things into pots
and think we’ve described them adequately, and they are
going to stay that way, but one of my favorite sayings is,
organisms do not read the book of rules we’ve written
for them. However, we teach it that way sometimes to try
to make sense of it, but when you get into the real-world
trenches, the truth is, we’re not able to do that. Organisms
are crossing all boundaries.”
www.healthcarehygienemagazine.com • october 2019
C. auris is insidious and still greatly unknown to hospitals
and healthcare systems, much like the early days of Clos-
tridium difficile. Experts are tending to agree that C. auris
has operated under the radar. Rhodes and Fisher (2019)
say that “Since its discovery, C. auris has caused a ‘stealthy
pandemic,’ emerging across the globe and is now recorded
in all continents except Antarctica. However, C. auris is
thought to have been misidentified as C. haemulonii on
several occasions, suggesting that C. auris has likely been
circulating as a human pathogen before 2009.”
Candida auris as a newly recognized cause of fungal
infection is catching healthcare professionals unawares,
despite cases being reported for nearly a decade now.
Since the first official isolation of Candida auris in 2009,
the scientific community has witnessed an exponential
emergence of infection episodes and outbreaks in different
world regions. According to the CDC as of June 30, 2019
(the most recent data available), there are 725 confirmed
cases, plus an additional 1,474 patients have been found
to be colonized with C. auris by targeted screening in 10
states with clinical cases.
“Candida, as a fungus, is an unusual and a difficult
problem to deal with,” Rohde says. “It’s not typically
something you would be looking for in a healthcare setting,
and certainly not looking for it in the common population.
But it is a factor when looking at the immunocompromised
population in context of environmental and healthcare
exposure; for example, could a patient have been working
in a certain environment where fungi and yeast are present?
But to have a fungus emerging and breeding in a healthcare
setting is a novel challenge in our lifetime. So, I think we
are trying to grasp what that means.”
He continues, “Microbiologists are very concerned about
C. auris because you almost have to rethink everything
from the laboratory perspective. If you are a clinician in a
smaller facility or a rural hospital, you often must wait on
sending specimens out to an off-site, more central clinical
laboratory, and that eats up valuable diagnostic time. You
can typically know pretty quickly if you have Staph or
Klebsiella or any of these other multi-resistant organisms if
you have access to rapid assays; but yeast and fungi are not
typically, at least right now, on the radar for panel testing.
Fortunately, it’s starting to get there, obviously, but if you
don’t have a trained medical laboratory professional on staff
who can look under a microscope or conduct some type
of test to rule out yeast — you could have some slippage
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