What Is Valley Fever?

Dust Storm approaching
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It is common for people visiting or relocating to the Phoenix area to be concerned about Valley Fever. While some contract Valley Fever, most people are not affected very severely, and many people never even know that they have it.

Still, it is essential to know about Valley Fever. According to the Arizona Department of Health Services, in 2016 there were more than 6,000 reported cases of Valley Fever reported in Arizona.

About Valley Fever

Valley Fever is a non-contagious lung infection. A fungus becomes airborne when the wind transports dust around construction areas and agricultural areas. When spores are inhaled, Valley Fever can result. The medical name for Valley Fever is coccidioidomycosis.

In the U.S. it is prevalent in the Southwest where temperatures are high, and the soils are dry. Arizona, California, Nevada, New Mexico, and Utah are primary locations, but there have been cases in other states as well.

It is estimated that about one-third of the people in the lower desert areas of Arizona have had Valley Fever at some point. Your chances of getting Valley Fever are about 1 out of 33, but the longer you live in the Desert Southwest, the higher your chances of infection. There are between 5,000 and 25,000 new cases of Valley Fever each year. You don't have to live there to get it—people visiting or traveling through the area have been infected, too.

Dogs can get Valley Fever and might need long-term medication. Horses, cattle sheep, and other animals can also get Valley Fever.

Valley Fever Risk Factors

Anyone can contract Valley Fever. Once infected, however, certain groups seem to have more instances of it spreading to other parts of their bodies; as far as gender is concerned, men are more likely than women, and, when considering race, African Americans and Filipinos are more likely to have the disease spread. People with compromised immune systems are also at risk. People ages 60-79 make up the highest percentage of reported cases.

Construction workers, farm workers or others who spend time working in dirt and dust are most likely to get Valley Fever. You are also at higher risk if you are caught in dust storms, or if your recreation, such as dirt biking or off-roading, takes you to dusty areas. One thing you can do to minimize your risk of getting Valley Fever is to wear a mask if you have to be out in blowing dust. Staying indoors in a dust storm is also recommended. Valley Fever is not contagious.


It usually takes between one and four weeks to become symptomatic if you contract Valley Fever.

About two-thirds of the people who are infected never notice any symptoms, or experience mild symptoms and never seek treatment. Those who have sought treatment showed signs including fatigue, cough, chest pain, fever, rash, headache, and joint aches. Sometimes people develop red bumps on their skin.
In about 5 percent of the cases, nodules develop on the lungs which might look like lung cancer in a chest x-ray. A biopsy or surgery may be necessary to determine if the bulge is a result of Valley Fever. Another 5 percent of people develop what is referred to as a lung cavity. This is most common with older people, and more than half of the cavities disappear after a while without treatment. If the lung cavity ruptures, however, there may be chest pain and difficulty breathing. Surgery may be needed.


Most people can fight off Valley Fever on their own without treatment. While it used to be thought that most people don't get Valley Fever more than once, the current statistics indicate that relapses are possible and would need to be treated again. For those who seek treatment, anti-fungal drugs (not antibiotics) are used. Although these treatments are often helpful, the disease may persist and years of treatment may be required. Less than 2 percent of the people who get Valley Fever die from it.

Pulmonary specialists and many area family physicians and hospitals are very familiar with Valley Fever. Physicians in other parts of the country seldom see cases of Valley Fever and, therefore, might not recognize it. Make sure your doctor knows that you have been to the Southwest and emphasize that you want to be tested for Valley Fever if you have any symptoms.

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