Increase in Reported Valley Fever Cases in California in 2017

SACRAMENTO November 14, 2017 – The California Department of Public Health (CDPH) today announced an increase in the number of new Valley Fever cases reported from local health departments in California through October 31, 2017, compared with the number of cases reported for the same period in 2016.

From January 1 through October 31, 2017, 5,121 provisional cases of Valley Fever were reported in California. This is an increase of 1,294 provisional cases from the provisional 3,827 cases reported during that same time period in 2016. The number of provisional cases provides a timely indicator of overall current activity, but the number of cases eventually confirmed is usually lower than the provisional number of cases reported.

The number of Valley Fever cases varies from year to year, and by season. Cases can be more common in the late summer and fall.  Provisional cases include suspect, probable, and confirmed cases: suspect and probable cases may be confirmed later or excluded as official Valley Fever cases upon further investigation.  CPDH is releasing the provisional data, since it provides an early indication of potential risk of Valley Fever in the current season.

It is unknown why there has been an apparent increase in provisional Valley Fever cases in California in 2017.

“With an increase in reported Valley Fever cases, it is important that people living, working, and travelling in California are aware of its symptoms, especially in the southern San Joaquin Valley and the Central Coast, where it is most common,” said CDPH Director and State Public Health Officer Dr. Karen Smith. “In these areas, anyone who develops flu-like symptoms, such as cough, fever, or difficulty breathing, lasting two weeks or more, should ask their health care provider about Valley Fever.”

Valley Fever, also known as coccidioidomycosis, is caused by the spore of a fungus that grows in soil in parts of California, Arizona, and other areas of the southwestern United States. People get infected by breathing in spores present in dust that gets into the air when it is windy or when soil is disturbed, such as through digging during construction.

A person can reduce the risk of infection by avoiding breathing in dirt or dust in areas where Valley Fever is common. In these areas, when it is windy outside and the air is dusty, stay inside and keep windows and doors closed. While driving, keep car windows closed and use recirculating air conditioning, if available. If you must be outdoors when it is windy and dusty, consider wearing a properly fitted mask (such as an N95 respirator mask, which is widely available in retail stores), and refrain from disturbing the soil whenever possible. Employers should train their workers about Valley Fever symptoms and take steps to limit workers’ exposure to dust.

Most infected people will not show signs of illness. Those who do become ill with Valley Fever may have symptoms similar to other illnesses, including influenza or bacterial or viral pneumonia, so Valley Fever is not always recognized. The flu-like symptoms can last for two weeks or more. While most people recover fully, some people are at risk for more severe disease or complications of Valley Fever such as pneumonia, infection of the brain, joints, bone, skin or other organs. People with an increased risk for severe disease include those 60 years or older, pregnant women, and people with diabetes or conditions that weaken their immune system. Additionally, African-Americans and Filipinos are at increased risk for severe disease, but the reason is unknown. If you think you have Valley Fever, you should contact your health care provider.

For additional information on Valley Fever, please visit the CDPH website.