Microscopic yeast strain Candida auris, also known as C auris, has been detected in more than half of US states since first emerging in the US in 2016.
Health officials warned of the fungus on Monday, reporting that the hospital-acquired infection had tripled in recent years and had become resistant to multiple drugs.
The Centers for Disease Control and Prevention (CDC) described the infection, which kills up to 60 percent of the people it infects, as an “urgent threat” back in 2019.
Symptoms of the fungus may not be noticeable because patients with C auris are usually already sick with another serious condition and are often hospitalized.
Most transmission occurs in healthcare facilities, especially among residents of long-term care facilities or those with internal devices – such as catheters, tracheostomies or wound drains – or on mechanical ventilators.
Fever and chills
Symptoms depend on the body part infected, but the most common sign in patients with Candida auris is persistent fever and chills.
Fever is defined as a temporary increase in average body temperature above 99°F to 99.5°F. But with a C auris infection, the higher temperature does not go away.
The most common sign in patients with Candida auris is persistent fever and chills
Chills are the body’s way of raising core temperature by shivering.
Fever and chills are the most common symptoms of Cauris bloodstream infections. Bloodstream infections can also cause confusion and disorientation.
Cauris can also live on the skin or other parts of the body, such as the ear or wounds, without causing an active infection and making you sick.
But in some patients, the fungus can enter the bloodstream and spread throughout the body, leading to potentially deadly invasive C auris infections, such as in the blood or internal organs.
This usually occurs when a medical device is inserted into the skin or gastrointestinal tract, such as a catheter or an IV.
Antibiotics don’t work
Another telltale sign of C auris is that the fever and chills cannot be treated with antibiotics for a suspected bacterial infection.
Antifungal medications may also be ineffective. Some C auris infections are resistant to all three types of antifungal medications: azoles, echinocandins, and amphotericin B. Echinocandins are the first line of therapy given to treat C auris.
Both antibiotics and antifungal medications may not be effective against C auris infections
Multidrug resistant strains of C auris have become more common in recent years.
Research from the CDC found that the number of cases of the fungus resistant to echinocandin had also risen — in 2021 there were about three times as many cases as in each of the previous two years.
Ear infection
Once the Cauris fungus has reached the ear, patients may experience a sharp or dull pain in the ear canal.
There may be a feeling of ‘fullness’ in the ears and hearing loss due to muffling. Drainage and nausea may also occur.
Patients may lose partial function of their ears if a C auris infection takes hold in the ear canal
The first case of C auris was found in the ear discharge of a 70-year-old female patient at Japan’s Tokyo Metropolitan Geriatric Hospital in 2009.
The fungus kills more than one in three people with invasive C auris where it has spread to cause an infection, such as in the ear.
Wound infection
Cauris can infect an existing open wound that is healing.
The skin around the wound may become inflamed and red. This is due to irritation that causes dilation of the blood capillaries.
The skin around an existing wound can become inflamed and red if the patient contracts C auris
Yellowish or orange pus may also come out of the wound.
The wound will be more painful and sensitive to the touch and will take longer to heal. There may also be an accompanying fever.
General fatigue and malaise
General fatigue and malaise is another sign of a bloodstream infection caused by C auris.
The feeling of fatigue is thought to signal the body to stop physical activity in order to recover.
General fatigue and malaise during a C auris infection can signal the body to stop physical activity
Bloodstream infection can also cause sepsis – which can be life-threatening. It occurs when chemicals in the bloodstream to fight an infection cause inflammation throughout the body.
This can cause multiple organ systems to become damaged and shut down.
Symptoms of sepsis include difficulty breathing, low blood pressure, increased heart rate, and mental confusion.
Cauris infections have been on the rise recently, with US cases rising from 1,310 in 2020 to 4,041 in 2021. There were 5,754 cases last year.
The CDC does not track how many people have died from C auris, and it can be difficult to know if patients have died from the fungus, as it usually infects people who are already very sick.
CDC data shows that fungal infections caused 7,000 deaths in the US and 1.5 million worldwide by 2021.
The hardest hit states are those with the highest number of hospitals – the breeding ground for Cauris.
The fungus does not form germ tubes and is rarely found in the natural environment.
Healthy people usually don’t get sick, but among the weak and vulnerable, it kills up to 60 percent.
People contract the Cauris by touching an infected person. Cauris can also be transmitted by touching contaminated surfaces or equipment, where it can survive for weeks.
Cauris showed up simultaneously in hospitals in India, South Africa and South America more than a decade ago. Researchers don’t know why, but speculate that climate change could have played a role.
Fungi usually can’t tolerate the warmer temperature of the human body, but scientists think C auris may have adapted to survive in a warming environment.
Another theory suggested in 2019 was that Ca auris may have existed as a plant fungus that adapted to exist in both salt water and warmer temperatures due to global warming.
The type of plant would have been a saprophyte – a plant that lacks chlorophyll but gets its food from dead organic matter.
Researchers at the University of Texas speculated that it could have subsequently been transmitted by birds from salt marshes around the world to rural areas where birds and humans often interact.
Researchers theorized the emergence of C auris
Cauris could have jumped into humans during activities such as farming, and eventually into hospitals and healthcare systems as people migrated to cities.
A research team in India pointed to Cauris from a tropical wetland and acquired antifungal resistance after coming into contact with humans.
There are about 1,500 species of yeast, which are unicellular fungi. They occur worldwide in the soil and on plants. Hundreds of varieties are used to make things like bread, beer and wine.
Some yeasts are dangerous pathogens for humans and other animals, especially Candida albicans, of which C auris is a type.