At least 19 people have contracted valley fever after attending the Lightning in a Bottle music festival in southern California in May, according to public health officials. The number of cases linked to the five-day event has nearly quadrupled in the past month, with eight of those infected requiring hospitalisation.
Valley fever is caused by inhaling the Coccidioides fungus, which is endemic to the soil of the US south-west. Most people exposed do not become ill, but a small percentage can develop serious, long-term complications. The disease typically presents as a mild respiratory illness.
Health officials have warned that valley fever cases have risen dramatically in recent years, driven by hotter and drier conditions linked to climate change. In California, reported cases more than tripled between 2000 and 2018, with over 9,000 cases recorded last year and more than 5,000 preliminary cases as of July 2024.
The California Department of Public Health (CDPH) highlighted that the Central Valley and central coast regions may face increased risk through autumn. Dr Tomás Aragón, the state public health officer, urged residents with lingering cough and fatigue to consult a doctor about valley fever, especially after exposure to dusty air in these areas.
The fungus grows in soil and can become airborne when disturbed, potentially travelling miles. The CDPH attributed the increase to winter rains following drought, better testing, and soil disturbance activities.
