We conducted a retrospective cohort study that tested 2,000 US military personnel for Coccidioides antibodies in a disease-endemic region. The overall incidence of seroconversion was 0.5 cases/100 person-years; 12.5% of persons who seroconverted had illnesses requiring medical care. No significant association was found between demographic characteristics and seroconversion or disease.
Keywords: California; Coccidioides; Naval Air Station Lemoore; San Joaquin Valley; United States; coccidioidomycosis; endemic diseases; fungi; infections; lung disease; military personnel; respiratory infections; risk; seroincidence.