About 60% of infected people do not develop any symptoms. Among those who are symptomatic, typically beginning one to three weeks after exposure to the spores, a spectrum of symptoms and signs may occur (see box below).
Symptoms and Signs of Primary Coccidioidomycosis
- Night sweats
- Chest pain
- Erythema nodosum
- Erythema multiform
Valley fever is the most common presentation and can include a self-limited flu-like illness and/or community acquired pneumonia (CAP) with fever, cough, chest pain, and headache. Systemic complaints — which include fatigue, myalgia, arthralgia, and night sweats — may last for weeks to months. Erythema nodosum and erythema multiforme also may occur. Chest radiograph findings may include diffuse pulmonary infiltrates, hilar adenopathy, and pleural effusion.
Complications are rare but can be severe. Approximately 5-10% of infections result in significant pulmonary disease and less than 1% result in extra-pulmonary disseminated disease that can involve multiple organ systems, last life-long, and lead to outcomes such as meningitis and death. Risk factors for severe or disseminated disease include immunosuppression (e.g. HIV/AIDS, TNF inhibitors, chemotherapy), diabetes mellitus, and pregnancy. In addition, some groups are at higher risk for complications including the elderly, African Americans, and persons of Filipino ethnicity.