There is growing interest in collecting wild fungi in Ireland but this is not supported by an appreciation of the associated dangers, according to researchers.

The issue constitutes a growing national health threat, wrote Dr. Douglas Hamilton and Dr. Gerard Meagher, from the department of public health, HSE Midlands in the first edition of Epi Insight Volume 21, Issue 1 for 2020.

They said there is currently no established coordination system for surveillance, public information and advice about wild mushrooms. Investment in effective prevention would lead to significant human and economic cost savings, the researchers reported.

The Health Protection Surveillance Centre (HPSC) is Ireland’s agency for surveillance of communicable diseases and part of the Health Service Executive (HSE).

Poisoning stats and case study
based on data from the National Poisons Information Centre, from the start of 2019 to end of September 2019, there were 18 confirmed mushroom poisonings, with two patients having had severe or life threatening symptoms. From the end of September to Nov. 19, 2019, a six more cases were recorded. From 2014 to 2018, there were 85 mushroom poisonings reported, with two being severe or life threatening.

The centre receives calls on ingestion of poisonous mushrooms. Poisonous mushrooms in the wild may be misidentified and used to cook meals, or unsupervised children may eat them from yards, parks or gardens. Incorrect mushroom identification by health professionals via the Internet has been reported.

The numbers compare to France wher more than 10,600 people were poisoned by mushrooms and 22 deaths were reported from 2010 to 2017.

In Ireland in September 2019 an individual developed liver failure after foraging for mushrooms in a local wood. They went to the hospital emergency department complaining of vomiting and abdominal pain, having eaten wild mushrooms the previous evening.

Admission was followed by rapid deterioration of liver function tests, transfer to the intensive care unit, and then to St Vincent’s University Hospital liver unit, wher an emergency liver transplant was done – all within three days.

The individual progressed well in the 24 hours post-transplant but deteriorated to multi-organ failure. This was followed by slow recovery, with weeks in ICU, remaining in hospital for almost three months. There was no underlying illness, history of viral hepatitis or use of medications so the incident was attributed to consumption of Amanita virosa. An expert mycologist consulted by the National Poisons Information Centre identified the mushroom as Amanita virosa known as the Destroying Angel. 

There are hundreds of different species of mushrooms growing in the Ireland. The Amanita genus is one of the most toxic worldwide and flourishes in Ireland. It is recognized by a bulbous cup around the base of the stem. It does not have a repugnant taste and can be mistaken for button mushrooms especially Amanita virosa. They tend to grow around broad leaved trees.

Raising public awareness
Most patients with mushroom poisoning experience minor symptoms, like nausea or one or two episodes of vomiting and only need normal fluid intake. Some toxic species can cause sweating, salivation, hallucinations, flushed skin, dilated pupils, delirium, and drowsiness.

Amanita cause severe vomiting and diarrhea followed by liver damage, sometimes leading to liver failure, even after consuming only one 30-gram mushroom. Amatoxins are thermo-stable so toxic effects are not reduced by cooking. Symptoms of vomiting are often delayed for more than six hours after ingestion.

The Food Safety Authority of Ireland (FSAI) has raised public awareness on poisonous mushrooms in the past, but as foraged berries and mushrooms are for personal consumption and not commercial foods it does not fall within its remit.

A campaign of social media, alerts, radio interviews and signs was held to raise awareness and may have prevented poisonings in the latter part of the season.

Hamilton and Meagher said awareness campaigns need to be repeated pre-season every year and a notification system for mushroom poisoning should be established.

They also said a coordination system for health protection should be determined with public health as the lead agency but including the National Poisons Information Centre and Safefood.