California health authorities have reported a rise in severe poisonings and deaths linked to the consumption of wild mushrooms, leading to renewed public health advisories. Since November 2025, at least 39 confirmed cases of mushroom poisoning and four deaths have been reported across multiple counties in Northern and Central California.
The cases are primarily associated with ingestion of the death cap mushroom (Amanita phalloides), a species responsible for the majority of fatal mushroom poisonings worldwide.
Adults across counties including Alameda, Contra Costa, Monterey, San Francisco, and Sonoma have been affected. One recent fatal case involved a man in his 60s from Contra Costa County who consumed foraged wild mushrooms later identified as death caps.
This marks the fourth death reported in recent months, as health authorities describe the situation as an unusual surge. On Tuesday, January 27, Contra Costa Health confirmed that a resident of Contra Costa County died after eating wild mushrooms.
Several patients required hospitalization for severe toxicity, and some developed acute liver failure necessitating liver transplantation, underscoring the seriousness of these exposures.1
Death cap mushrooms contain amatoxins, a group of heat-stable toxins that inhibit RNA polymerase II, an enzyme essential for protein synthesis in human cells. This mechanism leads to widespread cellular injury, with the liver being the most severely affected organ.1
A major risk factor is that death caps can closely resemble edible mushroom varieties, making visual identification unreliable for untrained individuals.
The poisonings have been reported primarily during late fall and winter, a period when rainfall supports extensive mushroom growth in California. Health officials note that recent weather conditions have led to increased proliferation of toxic wild mushrooms in parks, gardens, and residential areas.
Additionally, recent arrivals to California who are accustomed to foraging in their home country may mistake poisonous mushrooms in California for safe mushrooms foraged or cultivated in their native country. Foragers in California remain at high risk.
California Department of Public Health (CDPH)
Cases have occurred in both urban and suburban settings, increasing the risk of accidental exposure among the general public.
Symptoms of amatoxin poisoning typically appear 6 to 24 hours after ingestion, which can delay diagnosis. Early symptoms include nausea, vomiting, abdominal pain, and diarrhea.1
Patients may experience temporary symptom improvement, followed by rapid progression to severe liver injury within 48 to 96 hours. Without timely medical intervention, this can result in acute liver failure and death.1
Public health authorities emphasize that amatoxins are resistant to heat and food processing. Cooking, boiling, freezing, or drying mushrooms does not inactivate the toxins, making traditionally prepared wild mushrooms equally dangerous.1
For this reason, health officials advise consuming only commercially sourced mushrooms from regulated suppliers.
The California Department of Public Health has issued statewide warnings urging the public not to forage for or consume wild mushrooms. Healthcare professionals have been advised to consider mushroom poisoning in patients with unexplained gastrointestinal symptoms and to contact poison control services immediately.1
Early recognition and supportive treatment remain critical to improving patient outcomes.
Health agencies recommend avoiding all wild mushroom consumption, even among experienced foragers. Toxic species often closely resemble edible varieties, making misidentification common.
Avoidance of foraged mushrooms remains the most effective preventive strategy.
The recent increase in wild mushroom poisonings in California highlights a preventable cause of severe illness and death. Delayed symptom onset, toxin stability, and challenges in identification contribute to poor outcomes. Continued public awareness and adherence to health advisories are essential to reduce further cases.
Prompt medical evaluation after suspected ingestion, early poison control involvement, and awareness of the risk of acute liver failure requiring transplantation are critical to preventing additional fatalities.
California Department of Public Health. “Poisonous Mushrooms.” CDPH Environmental Health Investigations Branch. Accessed January 2026. https://www.cdph.ca.gov/Programs/CCDPHP/DEODC/EHIB/Pages/EIS/Poisonous-Mushrooms.aspx
SFGATE. “Wild Mushroom Poisonings Leave Four Dead in California.” SFGATE, January 2026.
(Rh/SS/MSM)
