Valley Fever: What You Need to Know After Being Infected at a California Music Festival

Several people were recently infected with a fungal lung infection at an outdoor music festival in California.

As of Aug. 21, at least 19 people who attended or worked at the “Lightning in a Bottle” festival in Kern County in late May have tested positive for valley fever, according to the California Department of Public Health. At least eight people have been hospitalized.

Additionally, a recent study found that cases of Valley Fever have increased dramatically in California over the past two decades and that droughts may play a role in seasonal spikes.

Here’s what you need to know about the infection, including signs and symptoms, how it’s treated and the best way to protect yourself.

What is Valley Fever?

Coccidioidomycosis, more commonly known as Valley fever, is a lung infection caused by inhaling spores of a fungus called Coccidioides, according to the Centers for Disease Control and Prevention (CDC).

“It’s a fungus that lives in the soil in certain parts of the world,” Dr. Daniel Pastula, chief of neuroinfectious diseases and global neurology at the University of Colorado School of Medicine and School of Public Health, told ABC News. “Generally, the Southwest, California and Arizona, are the main states where this is happening.”

He said the fungus can also be found in parts of Washington state, Mexico and parts of South and Central America during “hot, arid summers and mild winters.”

The disease is called Valley Fever because it was first discovered in the San Joaquin Valley, located in the southern half of California’s Central Valley.

There is currently no evidence of human-to-human transmission. The CDC says pets can also get valley fever, but there is no evidence of transmission between animals and humans.

People at greatest risk of developing serious illness include those with weakened immune systems, people with diabetes, older adults and pregnant women, according to the CDC.

What are the signs and symptoms?

Many people exposed to the fungus never develop symptoms. Those who do develop symptoms see signs about one to three weeks after exposure, according to the CDC.

Symptoms include cough, fever, headache, fatigue, shortness of breath, night sweats, muscle aches, joint pain, and rash.

Patients usually experience symptoms for a few weeks to a few months. If the infection becomes severe, symptoms may last longer.

Between 5 and 10 percent of patients with Valley fever may develop serious or long-term lung problems, and about 1 percent have the infection spread outside their lungs to other parts of the body, the CDC said.

“A very small portion of people who get it will develop what we consider pneumonia,” Dr. Rachael Lee, an associate professor in the department of infectious diseases at the University of Alabama at Birmingham, told ABC News. “You can see it on a chest X-ray. They may have a cough. They may lose weight.”

Should I get tested?

Because valley fever symptoms can mimic other infections, patients may want to consider getting tested if their symptoms do not improve, according to the CDPH.

People can have a blood test to confirm a diagnosis of valley fever, or a healthcare professional can perform a skin test to see if they have had valley fever in the past or are currently infected, the CDC said.

Lee said not all patients need to be tested and it may depend on their travel history.

“But if they’re going to California or Arizona and they’re concerned about being exposed to this virus,” doctors might consider testing them, she noted.

How is it treated?

In rare cases, valley fever can develop into meningitis, which is fatal if left untreated and may require lifelong antifungal treatment, according to the CDC.

“When people have disseminated infections that spread to the joints, bones, as well as the brain, more intense antifungal treatments, and potentially other treatments, are needed for these people,” Pastula said.

How to prevent valley fever?

There is currently no vaccine that protects against valley fever, although scientists continue to work on a vaccine, the CDC said.

It can be difficult to avoid inhaling the fungus in areas where it is prevalent, but there are steps people can take to reduce their exposure, experts say.

“If you’re not immunocompromised, do your best to not expose yourself to large amounts of dust, in general, especially if you’re in these areas of California and Arizona,” Lee said. “If you’re immunocompromised, I would suggest thinking carefully about where you’re going and what you’re doing. You could potentially wear something like a mask.” Many people with no or mild symptoms will see their infections clear up on their own without any medication.

However, for those who become more seriously ill or are at risk of serious illness, they may be prescribed an oral antifungal medication, such as fluconazole, for three to six months.

In rare cases, valley fever can develop into meningitis, which is fatal if left untreated and may require lifelong antifungal treatment, according to the CDC.

“When people have disseminated infections that spread to the joints, bones, as well as the brain, more intense antifungal treatments, and potentially other treatments, are needed for these people,” Pastula said.

How to prevent valley fever?

There is currently no vaccine that protects against valley fever, although scientists continue to work on a vaccine, the CDC said.

It can be difficult to avoid inhaling the fungus in areas where it is prevalent, but there are steps people can take to reduce their exposure, experts say.

“If you’re not immunocompromised, do your best to not expose yourself to large amounts of dust, in general, especially if you’re in these areas of California and Arizona,” Lee said. “If you’re immunocompromised, I would suggest thinking carefully about where you’re going and what you’re doing. You could potentially wear something like a mask.”

The CDC also recommends using indoor air filtration measures and thoroughly cleaning wounds with soap and water to reduce the risk of infection.

Pastula said it’s important for people to learn about mushrooms because climate change could cause Valley Fever to appear in other parts of the United States.

“Climate change could play a role in how (the mushroom) could live because this fungus has evolved into a specific ecological niche, and if that niche expands because of climate change, we’ll see (he) “We could potentially expand into areas that didn’t exist before,” he said.