Running News Daily

Tough Mudder Race in California Gets Even Tougher After Illness Spreads

More than 300 California runners have become sick with an unidentified virus following a mud run.

While Tough Mudder races are known to be grueling affairs that can take a toll on one’s body, an illness outbreak is affecting a large portion of California runners days after the race’s conclusion.

More than 300 participants in a recent Tough Mudder race in Sonoma County, California, have complained of rash, fever, muscle pain, nausea, and vomiting after the weekend event at Sonoma Raceway.

Matt Brown, a spokesman for Sonoma County, says that the 300 cases is just a “conservative estimate.”

“The Tough Mudder race involved extensive skin exposure to mud. Most affected persons have a 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 an advisory.

Brown said on Wednesday that Sonoma County is asking healthcare providers to obtain cultures from patients exhibiting symptoms and report back the results, but says that the cause of most of the infections is likely Aeromonas.

Aeromonas bacteria, commonly found in water, mud, and some types of food, can lead to gastrointestinal issues and other health issues such as kidney disease, meningitis, and skin and wound infections.

Charlie Bernard, a spokesman for Tough Mudder, said the company is working with county officials to investigate the event. Bernard says that Tough Mudder reached out to all participants and is sharing with them the health advisory. The organization urges people exhibiting unresolved or worsening rash, flu-like symptoms, fever, lethargy, and nerve pain to seek medical care.

“All necessary protocols were followed in preparation for, and during, the event,” Bernard wrote in an email to participants. “Our thoughts are with those affected, and we are actively investigating to understand exactly what occurred.”

In 2015, more than 1,500 runners in France experienced a norovirus after partaking in a mud run. In 2014, the CDC released a study of a mud run in Nevada two years prior that saw 22 runners fall ill afterward, also due to norovirus.