Valley fever risk rises as monsoon kicks up dust across Tucson

Tucson residents spending time outdoors during monsoon season should keep valley fever in mind, especially after storms send dust across neighborhoods, roads and open areas. Banner University Medicine is warning that the airborne dust can carry fungal spores capable of causing the infection, which may initially look like the flu, COVID or pneumonia. Because symptoms can take weeks to appear and early testing may miss the disease, health experts say people with illness that lingers or seems unusual should ask their doctors whether valley fever testing is appropriate.

Valley fever develops after a person inhales microscopic spores from a fungus that lives in desert soil. When monsoon winds and storms disturb the ground, those spores can become airborne. Dr. Fariba Donovan, an infectious disease specialist with Banner University Medicine and a researcher at the Valley Fever Center for Excellence at the University of Arizona College of Medicine in Tucson, said exposure is possible for anyone in the community. Dust storms are not the only concern, but they can increase the amount of soil and potentially infectious material moving through the air.

About 60 percent of people exposed to the fungus may never develop symptoms, according to Donovan. For others, the illness can begin with fever, chills, severe tiredness, headaches, a rash, joint pain and a reduced appetite. Those signs may not appear until two to four weeks after exposure, making it difficult for people to connect an illness with a recent storm or outdoor activity. Symptoms can also resemble several more familiar conditions, including influenza, COVID and bacterial pneumonia.

The length of the illness can offer an important clue. Donovan said someone with ordinary bacterial pneumonia or the flu often experiences acute symptoms for about a week before gradually improving. Valley fever can take longer, and persistent or atypical symptoms deserve further attention. She urged people who do not seem to be recovering from what appears to be a simple cold to discuss valley fever with their health care providers. An earlier diagnosis may also help patients avoid taking antibiotics for an infection that is not caused by bacteria.

Testing, however, is not always definitive at the beginning of the illness. Dr. Janice Blair of the Mayo Clinic’s Division of Infectious Diseases advised people to continue advocating for themselves when symptoms persist. Initial tests can miss valley fever, particularly early in the infection, so a person with a negative result may need to ask about follow-up testing if fever, fatigue or other concerning symptoms continue. Dr. Sanjay Patel, an allergist and immunologist with Modena Health in Scottsdale, said fever and fatigue are more worrisome for infection, while sneezing, a runny nose and itchy eyes may point more toward allergies.

Most infections do not become life threatening, but a small percentage can progress into severe disease. Valley fever can spread beyond the lungs and affect the brain, bones or other parts of the body. One possible complication is meningitis. People with weakened immune systems face greater risk, including those undergoing cancer treatment or chemotherapy, transplant recipients, immunocompromised patients and pregnant women. Still, patient experiences show that serious illness can also affect people who consider themselves healthy and active.

Chris Sams, who was diagnosed in 2017, initially experienced rapid weight loss, night sweats and a severe sensation of illness in his chest. His infection eventually disseminated, spreading from his lungs to his brain and spine. After hundreds of treatments and multiple surgeries, he continues to deal with exhaustion, fatigue and occasional night sweats. Asher Poole, diagnosed three years ago, experienced chest tightness and difficulty regulating his body temperature. About two weeks into his illness, he developed intense chills that were not relieved by warm baths. A chest X-ray later showed nodules in his lungs, although those nodules eventually disappeared.

The disease is not limited to people. Dust storms also raise concerns for pets, and veterinary experts have discussed the risk to animals exposed to disturbed desert soil. For Tucson households, that means paying attention to symptoms in both family members and pets after periods of dusty weather. People who become sick should share information about recent outdoor exposure and dust storms with their medical providers, particularly if they are not improving as expected.

Researchers are also working toward better prevention and faster diagnosis. Donovan said a valley fever vaccine has shown effectiveness in dogs, but it must still move through regulatory steps before it could be approved. Researchers are speaking with companies about supporting efforts to advance the vaccine toward human testing, with the long-term goal of developing what could become the first approved antifungal vaccine. In the meantime, Tucson residents cannot rely on a vaccine, and there is no simple way to know from symptoms alone whether a lingering illness is valley fever. Awareness during monsoon season, timely medical advice and follow-up testing when symptoms continue remain the main tools available.