SACRAMENTO — A record-breaking toxic mushroom outbreak has sickened 35 people and resulted in three deaths in California since mid-November. State health officials report that this is likely the largest outbreak of its kind in state history.
The California Poison Control System typically records fewer than five cases of mushroom poisoning each year. Rais Vohra, the system’s medical director, said an outbreak of this size has never happened before in Northern California.
Health officials have confirmed poisoning cases in nine Northern California counties: Alameda, Contra Costa, Monterey, San Francisco, San Luis Obispo, San Mateo, Santa Clara, Santa Cruz, and Sonoma.
Health Impacts
Eating these mushrooms has caused serious health problems. In addition to the three deaths, three people—including one child—suffered organ failure and required liver transplants. On Jan. 4, 2026, a Sonoma County resident died after eating poisonous death cap mushrooms.
The California Department of Public Health (CDPH) identified two types responsible for the poisonings: the Western destroying angel and the death cap mushroom. Experts say early rains and mild autumn temperatures created ideal conditions for these dangerous mushrooms to grow in large numbers.
Symptoms and Public Warning
Health authorities warned that symptoms of mushroom poisoning—such as nausea, vomiting, and stomach pain—typically do not appear until six to 24 hours after the mushrooms are eaten. This delay can be dangerous, as it may prevent people from seeking medical help until severe internal damage has already begun.
In response to the outbreak, the CDPH is advising the public to avoid picking wild mushrooms entirely. Because it is hard to tell the difference between poisonous and safe types, officials also urged residents to be extremely cautious when buying from street vendors or farmers' markets. Instead, they recommend buying mushrooms only from grocery stores.
