An outbreak of illnesses after a Tough Mudder race in Sonoma County, California, this month has reached about 300 cases, the county estimated Wednesday.
The Sonoma County Department of Health Services issued a health advisory last week after reports of rash, fever, muscle pain, nausea and vomiting among participants in the August 19-20 Tough Mudder event at Sonoma Raceway.
Matt Brown, a spokesman for Sonoma County, said Wednesday that 300 cases is a “conservative estimate.”
“The Tough Mudder race involved extensive skin exposure to mud. Most affected persons have pustular rash, fever, myalgias, and headache. These symptoms could be indicative of a minor illness called Swimmers’ Itch, but they can also indicate a Staph infection or other more serious bacterial infection such as Aeromonas,” the county said in its advisory.
Brown said Wednesday that the county is asking health care providers to take cultures from infected patients and report the results, but it’s “operating under the assumption that Aeromonas is the etiologic agent of most infections resulting from exposures at the event.”
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Aeromonas is bacteria often found in aquatic environments and can be found in mud and some types of food. Infection can lead to gastrointestinal symptoms and other complications, including kidney disease, meningitis, and skin and wound infections.
Charlie Bernard, a spokesman for Tough Mudder, said the company is working with the county and investigating the event. He said in an email that Tough Mudder has reached out to all registered participants and is communicating the county health advisory to spectators. It’s urging people to see a medical professional for “unresolved or worsening rash, flu-like symptoms, fever, lethargy (fatigue) or myalgia (nerve pain.)”
“All necessary protocols were followed in preparation for, and during, the event,” Bernard wrote. “Our thoughts are with those affected and we are actively investigating to understand exactly what occurred.”
