Risk factors for coccidioidomycosis, or valley fever, include lower respiratory tract symptoms lasting longer than 14 days, chest pain, rash, having lived in endemic areas fewer than 10 years, and diabetes mellitus or immunosuppressive conditions (strength of recommendation [SOR]: B, several prospective cohort and case-control studies).
The most common signs and symptoms include cough (74%), fever (56%), night sweats (35%), pleuritic chest pain (33%), chills (28%), dyspnea (27%), weight loss (21%), and rash (14%) (SOR: B, retrospective cohort study).
A 2013 surveillance report by the Centers for Disease Control and Prevention that included 111,717 patients in 28 states and the District of Columbia found an 8-fold increase in reported coccidioidomycosis in endemic areas from 1998 to 2011 (age-adjusted incidence rates: 5.3 per 100,000 in 1998 and 42.6 per 100,000 in 2011). Cases in nonendemic states increased 40-fold in the same time period, from 6 cases to 240.1 The disease is endemic in the southwest United States and northwest Mexico.
Risk factors include persistent symptoms, chest pain, diabetes, immunosuppression
A 2008 case-control study of 136 patients in Phoenix, Arizona (an endemic area) found that 15% of the patients diagnosed with community-acquired pneumonia (CAP) had coccidioidomycosis on serologic testing. Risk factors for CAP caused by coccidioidomycosis in this population were symptom duration longer than 14 days (odds ratio [OR]=5.0; 95% confidence interval [CI], 2.1-15.7), age younger than 18 years (OR=5.5; 95% CI, 2.1-15.3), chest pain (OR=4.6; 95% CI, 1.8-11.8), and diabetes mellitus or an immunosuppressive condition (OR=3.8; 95% CI, 1.0-16.5).2
Abnormal chest X-rays, myalgia— and a rash
A 2006 prospective cohort study of 55 patients in Tucson, Arizona, which is part of the endemic area, found that 29% of patients diagnosed with CAP tested serologically positive for coccidioidomycosis. Risk factors included fewer than 10 years of exposure to an endemic area (OR=4.11; 95% CI, 1.01-16.8). Chest radiograph abnormalities were more common in patients with CAP caused by coccidioidomycosis than patients without coccidioidomycosis (75% vs 25%, P=.005). Myalgia is more common when coccidioidal pneumonia is present (69% vs 23%, P=.0022).3