evidence: The most serious form of the disease, disseminated coccidioidomycosis, is uncommon. It occurs when the infection spreads (disseminates) beyond the lungs to other parts of the body. Most often these parts include the skin, bones, liver, brain, heart, and the membranes that protect the brain and spinal cord (meninges). [...] The spores are extremely small and can be carried far by the wind. Once inside the lungs, the spores reproduce, continuing the disease cycle. [...] Environmental exposure. Anyone who inhales the spores that cause valley fever is at risk of infection. People who live in areas where the fungi are common — especially those who spend a lot of time outdoors — have a greater risk.