January 15, 2026

San Mateo County Health is warning residents about the serious and potentially deadly risks of eating wild, foraged mushrooms following the illness of a San Mateo County resident linked to death cap mushroom poisoning.

Recent rain has contributed to the widespread growth of death cap mushrooms in California. The California Department of Public Health (CDPH) advises the public to avoid picking and eating wild mushrooms during this high-risk season. Death cap mushrooms, which are currently widespread in parts of Northern California and the Central Coast, contain amatoxins that can cause severe liver damage and death. These mushrooms are often found near trees such as oaks and pines and can be easily mistaken for edible varieties and also pose a risk to pets that may ingest them while outdoors.

“Death cap mushrooms are extremely dangerous and can be mistaken for mushrooms that look safe to eat.  No amount of cooking, boiling or drying makes these mushrooms safe,” said Dr. Kismet Baldwin-Santana, San Mateo County Health Officer.  “We recognize that mushroom hunting is a valued activity. However, the safest choice right now is to avoid eating any wild mushrooms. Even experienced foragers should exercise extreme caution and should not rely on AI-assisted field identification to distinguish between safe and poisonous mushrooms.”