SAN FRANCISCO (KGO) -- State health officials are warning of a spike in cases of valley fever.
The California Department of Public Health says it received reports of more than 5,300 cases of the illness in 2016.
A reason for the increase isn't known, but officials believe changes in testing, diagnosis and reporting patterns have had an impact.
People infected with valley fever may have flu-like symptoms.
It is prevalent in arid regions and can be contracted by breathing in fungus-laced spores from dust.
Click here for more information from the CDC.
California officials warn of spike in cases of valley fever