A cicada rests on a leaf.

What to Know About "Zombie Fungus" This Summer

May 23, 2024

Trillions of cicadas are emerging, and many are afflicted with a mind-control fungus. It sounds like the plot of a horror movie, but it is actually happening throughout many parts of the country this year as Brood XIII and Brood XIX emerge together for the first time in more than 200 years. 

We'll spare you the details on how the fungus, called Massospora cicadina, affects cicadas, but in short, it hijacks the cicada brain and uses it to fly around and spread its spores. And as alarming as that may sound, it doesn't pose any immediate threat to us. However, a different fungus, Candida, might be a bigger problem.

We asked Gregory Berry, PhD, Associate Professor of Pathology and Cell Biology at Columbia, about Candida fungi to learn how we can all help to stop the spread.

We always think about bacteria and viruses as the stuff that makes us sick, but fungus is a big problem, too. How big of a problem is it?

To put it all into context, mushrooms, molds, and yeast are all types of fungi, and millions of fungal species have existed on the planet for millions of years. Fungi are all around us and are unavoidable. In fact, many of them are even beneficial, serving critical roles in the ecosystem, food production, and new drug discovery, just to name a few. The good news is that only a few hundred kinds can make us sick.

The World Health Organization has listed 19 fungal species that they consider a "priority pathogen," but there is one that can potentially become a fungal pandemic. The Centers for Disease Control (CDC) has declared that the yeast Candida auris is a worsening global health threat. It is easily spread and can cause severe illness and even death in patients with serious underlying medical conditions. 

What is Candida, and where is it found?

Candida is the name for a group of yeast (a type of fungus) that can live on the body without causing health problems but can also cause a range of infections from mouth, skin, or vaginal yeast infections to very severe infections when it grows out of control. When this uncontrolled growth happens, infections can even become invasive and enter the bloodstream and then enter internal organs, such as the heart or brain. According to the CDC, about one in four patients with an invasive bloodstream Candida infection can die. It is that serious.

So, who can get a Candida fungal infection?

The typical types of Candida fungal infections can affect anyone, but certain factors can increase the risk. These include having a weakened immune system, having diabetes or other chronic health conditions, living in a warm and humid climate, or having close contact with someone with a fungal infection. 

But to be clear, when it comes to a deadly, invasive Candida infection, such as what is seen in a higher proportion with Candida auris, it almost exclusively affects people who are severely ill and are hospitalized or are in other healthcare facilities, such as nursing homes.

How do you know if you have a Candida infection?

Well, Candida symptoms are similar to bacterial infections and depend on where on the body the infection might be occurring, such as on the skin, mouth, or vagina. These infections can be diagnosed in the doctor's office based on presentation of symptoms or by the laboratory through a variety of different tests that would be ordered by your physician if an infection was suspected. 

However, invasive or bloodstream Candida infections cause severe symptoms with fever and chills and would lead to someone being hospitalized. At this point, a laboratory would perform various tests to diagnose a Candida auris infection.

How is it treated?

There are different types of antifungal medications to treat non-invasive Candida infections, including oral medications or topical ointments and creams. However, physicians may use antifungal drugs classes such as azoles, echinocandins, and polyenes for severe Candida infections. 

Physicians and researchers are sounding the alarm because some types of Candida have become drug-resistant and, therefore, more challenging to treat. For example, since 2021, Candida auris transmission has been on the rise, and some strains have been resistant to all three of the main classes of antifungal medications. This is why we must be aware of Candida auris and vigilant about stopping the spread in healthcare facilities.

So, how do we prevent and help stop the spread of non-invasive and invasive Candida fungal infections? 

For non-invasive, typical, and mild Candida infections, it is important to practice good hygiene and to keep the skin clean and dry in areas prone to sweating, especially as the summertime approaches. When it comes to these more common Candida infections, the general rule of thumb includes: 

  • Wear breathable, loose-fitting clothing, and choose clothing made from natural fibers like cotton, linen, and silk, which allow your skin to breathe. This can help prevent moisture buildup and reduce the risk of infection.
  • Keep skin clean and dry as fungi thrive in warm and humid environments, providing the perfect environment for it to grow. Take regular showers or baths, and use a mild soap to keep your skin clean. After bathing, make sure the skin is dry, paying attention to any skin folds and areas that tend to sweat more, especially in the summer heat. Changing out of wet or sweaty clothes quickly, especially socks and underwear, is also important. 
  • Avoid sharing personal items, such as towels, nail clippers, or shoes, as this can reduce the risk of transmission. 
  • Use antifungal products that can help prevent the growth of fungi and keep skin healthy. Talk to a doctor or pharmacist to find out which products to use.

When it comes to the invasive Candida auris fungal infection, it becomes a little trickier, but in general, good hygiene and proactive infection control measures practiced by the healthcare facility are essential in preventing the spread in healthcare environments, hospitals, and nursing homes. The most obvious practice is that everyone should wash their hands regularly and thoroughly and use hand sanitizers before and after seeing each new patient. In addition, there are many other infection control measures that are practiced by healthcare professionals every day.  

Lastly, when it comes to the impending influx of trillions of fungus-infected cicadas, are people at risk?

The short answer is no. There are some other fungal infections that can be transmitted from animals or insects to humans, but this is not one of them. One example of a fungal infection that can be spread between people and animals is ringworm, which is highly contagious and can be transmitted through direct contact with infected animals, such as dogs, cats, and farm animals. But some fungi, such as Massospora cicadina (the one infecting the cicadas), are specific to certain hosts and cannot survive and cause disease in other species. 

If you have any questions or think you might have a fungal infection, be sure to contact a physician. Physicians have the tools to accurately diagnose these infections, can order the right lab tests to make a definitive diagnosis, and can prescribe medications that are quite effective against most fungal infections.

References

Gregory Berry, PhD, is an Associate Professor of Pathology and Cell Biology at CUIMC.