What Is Valley Fever (Coccidioidomycosis)?

Valley Fever (coccidioidomycosis) is a fungal infection caused by breathing in Coccidioides, a fungus that resides in the soil of southwestern U.S. states and in Centra and South America. The spores of the fungus enter your body through your airways and settle into the lungs where they can grow into larger clusters of more spores. In severe cases, the fungus will continue to spread through the body. The spores get into the air by anything that disrupts the soil, such as farming, construction, or wind.

Valley fever can occur with flu-like symptoms, such as coughing, fever, and fatigue. Most people with valley fever never exhibit symptoms. Mild cases typically resolve on their own, but more severe cases lead to infection of the lungs. The infection is usually treated with antifungal medications. Valley fever most commonly affects people 60 years or older. About 20,000 people a year are diagnosed with valley fever, and it occurs most commonly in Arizona and California.

Signs and Symptoms

Most people with valley fever experience no symptoms. Those who are symptomatic have cold, flu-like, or symptoms of pneumonia and usually become symptomatic 5-21 days after exposure to the fungus. Symptoms usually resolve on their own after a few weeks or months. If symptoms do not resolve and a person experiences chronic symptoms in their lungs, it is referred to as chronic pulmonary coccidioidomycosis. Symptoms of valley fever include:

• Chest pain (mild to severe)
• Swollen ankles, feet, or legs
• Cough (sometimes producing phlegm with blood)
• Shortness of breath
• Headache
• Fever and night sweats
• Muscle aches and pains, joint stiffness
• Loss of appetite
• Painful red lumps on lower legs (erythema nodosum) 

In rarer instances, severe disease will spread to other areas of the body through the bloodstream. Symptoms include:

• Change in mental status
• Enlarged or draining lymph nodes
• Severe lung symptoms
• Neck stiffness
• Joint swelling
• Weight loss
• Light sensitivity 

If valley fever has a presentation with skin lesions, it is usually indicative of disseminated disease. Skin lesions associated with widespread disease typically appear on the face. If coccidioidomycosis spreads to the brain, it can develop into coccidioidomycosis meningitis, which is a life-threatening condition.

Symptoms include:

• Headaches
• Blurred vision
• Hearing changes
• Confusion
• Neck stiffness
• Light sensitivity

Causes

Valley fever is caused by caused by breathing in Coccidioides, a fungus that resides in the soil of southwestern U.S. states and in Centra and South America. The spores of the fungus enter your body through your airways and settle into the lungs where they can grow into larger clusters of more spores. The spores and how your immune system responds to them is what causes your symptoms. In severe cases, the fungus will continue to spread through the body. The spores get into the air by anything that disrupts the soil, such as farming, construction, or wind.

Risk Factors

There are several risk factors that increase your risk of developing valley fever. Risk factors include:

• Age (60 years or older)
• Compromised immune systems (through disease or medications that suppress the immune system
• Diabetes or HIV/AIDS
• Pregnancy (being in your third trimester)
• Race (black or Filipino)
• Working jobs that expose you to soil (with the fungus spores)
• Environmental exposure (living or traveling in areas where fungus resides) 

Diagnosis

Valley fever can be difficult to diagnose, as it shares symptoms with several other conditions. To diagnose valley fever, your doctor will evaluate your symptoms, take a thorough medical history, and perform a physical examination. Your doctor may also ask questions about environmental exposures from traveling. Additionally, your doctor may recommend other diagnostic tests.

These tests may include:

• Blood tests. This test can detect antibodies or antigens that show signs of coccidioides.
• Sputum culture. This test collects a sample of matter that is discharged from coughing and assesses for the presence of coccidioides organisms.
• Imaging tests (X-ray, MRI, CT scan). Imaging tests can detect any lung abnormalities or issues with lung functioning.
• Lung biopsy. This procedure removes a tissue sample from your lungs to be analyzed by a lab and assessed for the presence of coccidioides. 

Treatment

Depending on how severe your symptoms are, or if you are at a higher risk for severe disease, your doctor will either take a watch and wait approach (monitoring your symptoms) or will start you on antifungal medications. The most common antifungal medications used to treat valley fever include:

• Fluconazole
• Itraconazole
• Amphotericin B (AmB) 

Typically, antifungal medications will be taken for 3-6 months, but may last longer if symptoms are more severe.

Prevention

It may be difficult to avoid exposure to coccidioides if you live in areas where the fungus exists. However, there are several preventative measures you can take to help reduce your risk of breathing in the spores. Prevention measures include:

• Avoid areas where you would be exposed to dust or soil
• If exposure is likely, wear an N95 respirator mask to filter out the fungal spores from the air you breathe
• Make sure to close your windows and stay inside during dust storms
• Avoid activities like gardening or digging in soil, which could expose you to the fungal spores
• If you must dig in the soil, get the soil wet before digging to decrease the risk of breathing in the soil dust
• Use appropriate air filters indoors
• Wash in scrape or cut with soap and water to avoid fungal skin infections 

Complications

Complications from coccidioidomycosis may include:

• Severe pneumonia. Most people who develop pneumonia from valley fever eventually recover. However, people of Filipino or African heritage, or people with compromised immune systems may become seriously ill.
• Ruptured lung nodules. There is a small portion of people who develop thin-walled nodules in the lungs with valley fever. Usually, the nodules go away without causing problems, however, some nodules may rupture causing chest pain and breathing problems. Ruptured lung nodules sometimes require a procedure or surgery to be repaired.
• Disseminated disease. This is the most serious and severe of complications from valley fever. Disseminated disease means the disease has spread throughout the body. This complication can cause problems such as skin ulcers or lesions, heart inflammation, severe joint pain or stiffness, urinary tract problems, and meningitis. Meningitis can be life-threatening.