Fungal Infections Worldwide are Becoming Resistant to Drugs and are More Deadly
Editor ’ s note
This piece originally was published June 28 , 2021 in The Conversation and is reprinted under Creative Commons . under the microscope
By Rodney E . Rohde , PhD , MS , SM ( ASCP ) CM SVCM , MBCM , FACSc
Say “ fungus ” and most people in the world would probably visualize a mushroom . But this fascinating and beautiful group of microbes has offered the world more than just foods like edible mushrooms . Fungi are also a source of antibiotics – for example , penicillin from penicillium – as well as the yeasts and other fermentation agents that make bread rise , give cheese its flavor and put the alcohol in wine and beer .
Many people may also not realize that some fungi can cause disease . However , athlete ’ s foot , thrush , ringworm and other ailments are caused by fungi , and some are serious risks to health and life . That ’ s why the rise of antifungal resistance is a problem that needs more widespread attention – one equal to the better-recognized crises of multidrug-resistant microbes like the bacteria that cause tuberculosis .
I ’ ve worked in public health and medical laboratories for over three decades , specializing in public health and clinical microbiology , antimicrobial resistance and accurate science communication and health literacy . I ’ ve been paying close attention to the growing resistance of a pathogenic fungus called Candida auris to limited and commonly used anti-fungal agents . Since fungi have traditionally not caused major diseases , the emergence of drug-resistant fungi that can cause serious illness rarely receives funding for medical research . But the facts suggest that this needs to change .
Most fungal infections worldwide are caused by a genus of fungi called Candida , particularly the species called Candida albicans . But there are others , including Candida auris , which was first identified from an external ear canal discharge in 2009 in Japan , and given its name for the Latin term for ear , “ auris .”
Candida normally lives on the skin and inside the body , such as in the mouth , throat , gut and vagina , without causing any problems . It exists as a yeast and is thought of as normal flora , or the microbes that are part of humans . Only if our bodies are immuno-compromised do these fungi become opportunistic and cause disease . That is what ’ s happening worldwide with multidrug-resistant C . auris .
Infections by C . auris , sometimes called fungemia , have been reported in 30 or more countries , including the United States . They are often found in the blood , urine , sputum , ear discharge , cerebrospinal fluid and soft tissue , and occur in people of all ages .
According to the Centers for Disease Control and Prevention ( CDC ), the mortality rate in the U . S . has been reported to be between 30 percent to 60 percent in many patients who had other serious illnesses . In a 2018 overview of research to date about the global spread of the fungus , researchers estimated mortality rates
Multidrugresistant Candida auris can cause serious infections among patients in hospitals and other group medical care settings . Courtesy of Science
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of 30 percent to 70 percent in C . auris outbreaks among critically ill patients in intensive care .
Research data shows that risk factors include recent surgery , diabetes and broad-spectrum antibiotic and antifungal use . People who are immuno-compromised are at greater risk than those with healthy immune systems .
C . auris can be difficult to identify with conventional microbiological culture techniques , which leads to frequent misidentification and under recognition . This yeast is also known for its tenacity to easily colonize the human body and environment , including medical devices . People in nursing homes and patients who have lines and tubes that go into their bodies – like breathing tubes , feeding tubes and central venous catheters – seem to be at highest risk .
The Centers for Disease Control and Prevention have set C . auris infections at an “ urgent ” threat level because 90 percent are resistant to at least one antifungal , 30 percent to two antifungals , and some are resistant to all three available classes of antifungals . This multidrug resistance has led to outbreaks in healthcare settings , especially hospitals and nursing homes , that are extremely difficult to control .
For hospitalized COVID-19 patients , antimicrobial-resistant infections may be a particularly devastating risk of hospitalization . The mechanical ventilators often used to treat serious COVID-19 are breeding grounds and highways for entry of environmental microbes like C . auris .
Further , according to a September 2020 paper authored by researchers Anuradha Chowdhary and Amit Sharma , hospitals in India treating COVID-19 have detected C . auris on surfaces including “ bed rails , IV poles , beds , air conditioner ducts , windows and hospital floors .” The researchers termed the fungus a “ lurking scourge ” amid the COVID-19 pandemic .
The same researchers reported in a November 2020 publication that of 596 COVID-19-confirmed patients in a New Delhi ICU from April 2020 to July 2020 , 420 patients required mechanical ventilation . Fifteen of these patients were infected with candidemia fungal disease and eight of those infected ( 53 percent ) died . Ten of the 15 patients were infected with C . auris ; six of them died ( 60 percent ).
With the options for effective antifungals narrowing , CDC is recommending a focus on stopping C . auris infections before they start . These steps include better hand hygiene and improving infection prevention and control in medical care settings , judicious and thoughtful use of antimicrobial medications , and stronger regulation limiting the over-the-counter availability of antibiotics .
Rodney E . Rohde , PhD , MS , SM ( ASCP ) CM SVCM , MBCM , FACSc , serves as chair and professor of the Clinical Laboratory Science Program at Texas State University . Follow him on Twitter @ RodneyRohde / @ TXST _ CLS , or on his website : http :// rodneyerohde . wp . txstate . edu /