Valley Fever: Awareness is Key
Valley fever is caused by Coccidioides, a fungus that lives in soil in the southwestern United States and parts of Mexico, Central America, and South America. Inhaling the airborne fungal spores can cause an infection called coccidioidomycosis, which is also known as “cocci” or “valley fever.” Most people who are exposed to the fungus do not get sick, but some people develop flu-like symptoms that may last for weeks to months. In a very small proportion of people who get valley fever, the infection can spread from the lungs to the rest of the body and cause more severe conditions, such as meningitis or even death. Valley fever cannot spread from person to person.
A Silent Epidemic
Most cases of valley fever in the US occur in people who live in or have traveled to the southwestern United States, especially Arizona and California. The map below, “Areas where valley fever is endemic,” was generated from studies in the 1950s, and shows the areas where the fungus that causes valley fever is thought to be endemic, or native and common in the environment. The full extent of the current endemic areas is unknown and is a subject for further study.
A March 2013 MMWR article notes that more than 20,000 cases of valley fever are reported each year in the United States, but many more cases likely go undiagnosed. Some researchers estimate that each year the fungus infects more than 150,000 people, many of whom are sick without knowing the cause or have cases so mild they aren’t detected.
The annual number of cases has been increasing in recent years, and this could be because of higher numbers of people exposed to the fungus or because of changes in the way cases are being detected and reported.
It Only Takes One Breath
Areas Where Valley Fever is Endemic
Anyone can get valley fever, including children. However, it is most common among older adults, particularly those 60 and older. People who have recently moved to an area where the disease naturally occurs are at higher risk for infection.
Several groups of people are at higher risk for developing the severe forms of valley fever, including:
- African Americans
- Women in their 3rd trimester of pregnancy
- People with weak immune systems, including those with an organ transplant or who have HIV/AIDS
Emily’s Story: Valley Fever Derails Young Dancer
Seven-year-old Emily Gorospe loved to dance. She would twirl in her bedroom, holding her colorful, ruffled costumes as if they were her dancing partners.
But Emily no longer has the energy to dance – let alone walk down the hallway of her family’s home. Since contracting valley fever earlier this year, the fungus has robbed the little dancer of playing outside during recess or even doing her homework.
“Tired doesn’t do it justice,” said Valerie Gorospe, Emily’s mom, as she sat on the floor of their home in Delano, south of Fresno, California.
Read more about Gorospe’s and other people’s ongoing fights with valley fever, including the problems of misdiagnosis.
What Healthcare Providers Should Know
Be aware that the symptoms of valley fever are similar to those of other common respiratory infections. Consider testing for valley fever in patients with flu-like symptoms who live in or have traveled to the southwestern United States.
Common Symptoms, Unusual Cause
Symptoms of valley fever typically appear between 1 and 3 weeks after a person inhales the fungal spores, and may include:
- Muscle aches
- Joint pain
In severe cases, valley fever can cause chronic pneumonia (lung infection), meningitis (spine and brain infection), or infection in the bones and joints. Because the symptoms of valley fever are similar to other more common illnesses, diagnosis and treatment are often delayed.
What You Need to Know
It is difficult to avoid exposure to the fungus that causes valley fever, and there is no vaccine to prevent the infection. Therefore, if you have symptoms of valley fever and you live in or have visited an area where the fungus that causes the infection is common in the environment, ask your doctor to test you for valley fever. If you have valley fever, you may need treatment with prescription antifungal medication.
Research is needed to find out the best treatment for valley fever. Other research is under way to develop a vaccine to prevent valley fever and to create better antifungal medications.
Studying Cocci’s Changing Footprint
Scientists in California and Arizona are studying how changing weather patterns affect the habitat of Coccidioides, the fungus that causes valley fever. Experts are concerned that hotter temperatures could cause the habitat to expand beyond the traditional southwestern “hot spots.” Through computer mapping and soil sampling, scientists are testing a theory that spikes in rainfall followed by dry spells could leave the resilient fungus exposed and airborne, giving it the potential to cause illness.
The CDC would like to thank the Reporting on Health Collaborative for sharing stories about valley fever. “Just One Breath” is a series of investigative reports that aim to raise awareness about valley fever and the people it affects. The project is an initiative of the USC Annenberg School of Journalism.
- CDC Coccidioidomycosis (Valley Fever) Homepage
- CDC Yellow Book: Coccidioidomycosis
- Coccidioidomycosis (Valley Fever), Arizona Department of Health Services
- Reporting on Health Just One Breath Series
- In the news:
- Fungal diseases
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