What is Valley Fever?

Valley Fever (medical name coccidioidomycosis or "cocci" for short) is an infection in the lungs caused by a fungus (scientific name Coccidioides immitis) that grows in the soil in the southern and central portions of California, Arizona, New Mexico, Texas and the southern portions of Nevada and Utah. Valley Fever is also found in parts of Mexico, Central and South America. These areas where the fungus grows in the soil are called "endemic."

Who can get Valley Fever?

Anyone who lives, visits, or travels through the areas where the fungus grows in the soil may acquire Valley Fever. People working in certain occupations such as construction, excavation, agriculture, archaeological digging and other occupations which disturb soil in endemic areas may be at increased risk of exposure. Persons who pursue recreational activities such as biking or driving ATVs or 4-wheel drive vehicles in the desert may be at increased risk. Various domestic animals such as dogs and horses as well as wild animals are also susceptible.

How is Valley Fever spread?

Valley Fever is acquired by inhaling one or more airborne spores of the fungus Coccidioides immitis. The spores are carried in dust particles from the soil by the wind when the desert soil is disturbed.

Valley Fever is NOT spread from human to human, or animal to animal, or animal to human, or human to animal. The spores change form in tissues of the body and are not contagious in tissue form.

What are the symptoms of Valley Fever?

Most cases (60%) have no symptoms or only very mild flu-like symptoms and do not see a doctor. When symptoms are present, the most common are fatigue, cough, fever, profuse sweating at night, loss of appetite, chest pain, generalized muscle and joint aches particularly of the ankles and knees. There may also be a rash that resembles measles or hives but develops more often as tender red bumps on the shins or forearms.

Patients with chronic Valley Fever infections present with chronic systemic symptoms such as low grade fever, weight loss, cough, chest pain and hemoptysis. These symptoms are often indolent and resemble tuberculosis when coupled with x-ray findings.

How long does it take for symptoms to appear?

Symptoms usually develop within 7-28 days after exposure.

What is dissemination?

Dissemination is the spread of the fungal infection from the lungs to other parts of the body. The most common sites of dissemination in Valley Fever are skin, bones, joints and brain meninges. Cocci meningitis is the most lethal.

What is the treatment for Valley Fever?

Before the availability of antifungal medications, the natural history of initial pulmonary infections was determined to resolve in at least 95% of patients. Studies have not been completed yet to determine if drug therapy hastens the resolution of immediate symptoms or prevents subsequent complications. The physician usually monitors the progress of the patient by chest x-rays, following the cocci serology (blood test) titer and the severity and duration of symptoms. This may require frequent visits to the doctor. If weight loss and night sweats continue, infiltrates in the lungs enlarge, and the inability to work persists, antifungal medication usually is considered.

What can be done to prevent Valley Fever?

There is no prevention or vaccine at this time. Avoiding activities associated with dust and airborne dirt of native desert soil is recommended, but it is not a certain means of prevention. Some occupations recommend wearing masks. Use common sense and stay out of the blowing dust.

The following information was taken from the Valley Fever Center for Excellence website FAQ.

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