Graph shows the ups and downs of Valley Fever cases in San Luis Obispo County and the direct correlation between dry years and wet ones. From a former high of 445 cases in 2017, when the last drought started, and the steady decline as the dry years up, until 2023, when the rains returned and cases started the uptick to 2024, setting a new, all-time record. Graph courtesy SLO County
The San Luis Obispo County Health Department is warning of a record number of cases of Valley Fever last year.
“More San Luis Obispo County residents were diagnosed with Valley fever in 2024 than any previous year on record,” reads a news release from the Health Department, “with 482 cases reported to the Public Health Department during the calendar year.
“This is nearly double the 244 cases reported in 2023 and greater than the previous highest count of 445 cases in 2017.”
County Health Officer, Dr. Penny Borenstein, wasn’t surprised in the jump. “This increase is not unexpected, as Valley Fever is known to increase after periods of drought followed by heavy rain.
“We’ve been working to ensure our healthcare providers and community know to be on the lookout for this disease and know how to reduce your risk. If you experience flu-like symptoms such as fever and cough for more than a few weeks, I recommend talking with your healthcare provider and asking to be tested for Valley Fever.”
Valley Fever is caused by the fungus, coccidioides, that lives naturally in the soil here. It can also be found in the soils of neighboring counties, the Central Valley and “other parts of the Southwest,” in particular Arizona.
The fungus releases spores into the air whenever soil is disturbed by grading or digging, and even by the wind.
“People can breathe in dust that contains spores from this fungus, leading to infection,” The Health Department said.
Not everyone who breathes in the spores gets sick. “About 60-percent of people who become infected with Valley Fever do not experience any symptoms and do not need treatment,” the Health Department said. “Around 30-40 percent of people develop sudden flu-like symptoms and get well on their own in a few weeks without medical treatment.”
Some folks, however, get very sick. “About one percent of people who have symptoms experience a more serious form of the disease in which the infection spreads throughout the body.”
They’re pretty sure what causes outbreaks like in 2024. “Large amounts of rainfall following periods of drought have been shown to increase the amount of fungus growing in the soil,” the County said, “increasing the risk of Valley Fever.”
To be safe, you should avoid breathing in a lot of dust. But that’s easier said than done.
“It would be nearly impossible to avoid all exposure to dirt,” the Department said, “but you can limit your risk. Try to avoid areas with a lot of dust, especially on windy days. If you need to spend time in a dusty area, take precautions such as wearing an N95 mask and dampening the soil to prevent it from drifting into the air.”
One can get a lungful of dirty air even when driving a car. “If you are driving in areas with high winds or visible dust, close your windows and set the A/C to recirculate.”
Animals — dogs, cats, horses and others — can also get infected with Valley Fever, but it cannot be passed from one person to another.
According to the Health Department, anyone can get Valley Fever, including healthy adults and children. “People who live, work, or spend time outdoors near areas where dust and dirt are stirred up have a higher risk of getting Valley Fever.”
The Health Department has a Valley Fever webpage, see: bit.ly/3EB2aUj for more information about this disease.
