What is ‘Valley Fever?’ California cases reach alarming levels, set to break previous records

California reports 6,761 Valley Fever cases by July 2025, potentially surpassing the 2024 record of 12,595. The illness poses risks due to climate change.

California has witnessed thousands of Valley Fever cases this year, and the numbers seem poised to surpass past records.

The fungus that causes Valley Fever, sometimes called coccidioidomycosis or “cocci,” develops in the soil in various areas of California and other southwestern states. (AFP)

According to data shared by the California Department of Public Health, 6,761 cases were reported by the end of July 2025. If the present rate of cases continues, it would surpass the highest record of 12,595 cases in 2024.

In the US, the number of Valley Fever cases has been rising since 2000. In 2019, there were over 9,000 cases, up from less than 1,000 cases reported each year in 2000. The spike has alarmed researchers and health officials since it appears that cases might continue to climb in the years to come as a result of climate change.

What is Valley Fever? Here's what we know

The fungus that causes Valley Fever, sometimes called coccidioidomycosis or “cocci,” develops in the soil in various areas of California and other southwestern states.

Both humans and animals are susceptible to the Valley Fever, and it is transmitted via airborne spores that are inhaled into the lungs. It causes respiratory symptoms like fever, coughing, chest pain, and fatigue.

According to the Centers for Disease Control and Prevention (CDC), it is frequently misdiagnosed or goes untreated due to its symptoms' resemblance to those of other respiratory illnesses, including pneumonia and even COVID. As a result, some patients may receive poor treatment or have delays in receiving the proper care.

Some people may inhale the spores and not become unwell, while others are prone to acquire a more serious sickness.

Those who are particularly susceptible include pregnant women, people with weakened immune systems, people over 60, people with diabetes, and people who work in construction or other jobs where they are frequently exposed to dust and dirt.

As per the CDC, 1 percent of individuals who contract Valley Fever may experience an infection that expands from their lungs to other parts of their body, including their skin, bones, joints, or brain, and 5 to 10 percent may experience severe or permanent lung difficulties.

While many patients can recover on their own in a few weeks or months without therapy, some may need treatment, hospitalisation and antifungal medication for more severe infections.