1 Dead, Nearly 2 Dozen Sickened In CA Poisoning Outbreak Linked To Mushrooms

California health officials are cautioning residents about foraging after an outbreak of poisoning linked to wild mushrooms killed one person and sickened nearly two dozen others.

The California Department of Public Health on Friday issued an advisory following a recent outbreak of amatoxin poisoning linked to the consumption of wild death cap mushrooms.

As of Dec. 5, the state had confirmed 21 adult and pediatric cases, with significant clusters reported in the Monterey and San Francisco Bay areas. Residents in Monterey County became ill after eating mushrooms found in a local park, according to county health officials.

Several patients have required intensive care, with at least one individual potentially needing a liver transplant, officials said. One adult fatality has also been reported to date.

“Death cap mushrooms contain potentially deadly toxins that can lead to liver failure, said Dr. Erica Pan, CDPH Director and state public health officer. “Because the death cap can easily be mistaken for edible safe mushrooms, we advise the public not to forage for wild mushrooms at all during this high-risk season.”

Wet weather fuels the growth of death cap mushrooms, which are found in many parts of California, particularly near oaks and other hardwood trees, including pine trees.

The death cap mushroom and the “destroying angel” mushroom look and taste similar to edible mushrooms, so experts warn that a mushroom's color is not a reliable way of detecting its toxicity. Cooking, boiling, drying or freezing the mushrooms does not make them safe to eat.

There were more than 4,500 cases of exposure to unidentified mushrooms logged at America's Poison Centers in 2023, according to their National Poison Data System annual report. Roughly half were in young children, who experts warn may pick and eat a mushroom while playing outside

California's poison control system sees hundreds of cases of wild mushroom poisonings each year, officials said.

Symptoms of amatoxin poisoning include watery diarrhea, nausea, vomiting, abdominal pain and dehydration, and can occur within 6 to 24 hours following ingestion of toxic mushrooms. Symptoms generally subside within a day.

However, this brief improvement can be deceptive, officials said, as people may still develop serious to fatal liver damage within 48 to 96 hours after eating the mushrooms.

For more information, contact the California Poison Control System or visit the CDPH website.

The Associated Press contributed reporting.