Over 100 individuals have reported contracting bacterial infections after participating in a Tough Mudder challenge in Sonoma, California over the weekend. The event, which took place at Sonoma Raceway, involved participants navigating through a muddy obstacle course by running, wading, and crawling. Three days following the event, the Sonoma County Department of Health Services issued a health advisory for all racers, as multiple reports of rashes, fever, muscle pains, and vomiting were received.
The health advisory mentioned that these symptoms could be indications of a minor illness known as Swimmers’ Itch, but they could also signify a Staph infection or other more serious bacterial infection, such as Aeromonas. While Swimmers’ Itch is a rash caused by water parasites and usually does not require medical attention, Staph infections are caused by bacteria and can produce swollen, pus-filled bumps on the skin. If left untreated, Staph infections can lead to lung infections or sepsis. Aeromonas hydrophila, also found in water, can cause infections with symptoms such as fever, diarrhea, cramps, and vomiting.
On Wednesday, 112 participants reached out to Tough Mudder to report infections resembling bumpy, pus-filled rashes. The email, obtained by NBC News, stated that it represented 344 participants, including family members and friends who also took part in the race. The email mentioned that “most of our doctors” had identified the infections as staph and that many individuals experienced additional symptoms such as fever and fatigue. Several participants had even been hospitalized for days.
Tough Mudder has not yet responded to requests for comment; however, in a reply to the email sent by the affected participants, a representative from Tough Mudder assured that the organization was conducting its own investigation, working to ensure that the health advisory reached all participants, and assisting the Sonoma County health department.
NBC News interviewed five people who reported experiencing symptoms of bacterial infection after participating in the Tough Mudder race on Sunday. One participant, David Long, revealed that he raced with co-workers and developed a fever, chills, and lesions on his body from ankle to chest that very night. Long sought medical attention the next day and tested positive for Aeromonas infection.
The Sonoma County health department confirmed receiving several calls and emails from participants expressing concerns about their health or reporting symptoms. So far, the county has recorded seven cases of Aeromonas hydrophila infection based on physician reports.
Founded in 2009, Tough Mudder organizes races across the country, including 5k, 10k, and 15k challenges where participants are fully immersed in muddy terrain, crawling through mud under barbed wire, and scaling slippery hills. After last year’s event in Sonoma County, a participant emailed Tough Mudder to report that she and her friends who had participated developed fevers and rashes. This year, the group email to Tough Mudder expressed frustration that the company failed to inform participants about the previous complaints.
Dr. Henry Chambers, the chief of the Division of Infectious Diseases at San Francisco General Hospital, explained that mud can harbor thousands of bacteria species. Crawling through muddy terrain, especially with cuts and scrapes from obstacles, carries an inherent risk of infection. Chambers advised participants to immediately clean off and shower after completing the course to prevent organisms from establishing themselves. Testing the area beforehand might have detected Aeromonas bacteria; however, he noted that this type of course presents various infection risks beyond that particular one.
Malia Helms, one of the participants, woke up the morning after the race with itchy, painful red bumps all over her body. Helms tested positive for Aeromonas infection and expressed her disappointment that the company failed to inform this year’s participants about the potential risk. Another member of Helms’ group, Noa Umbaugh, woke up with similar bumps on her arms and legs but did not test positive for Aeromonas infection. Umbaugh emailed Tough Mudder to report her symptoms, and the company responded by stating they were looking into the matter.
Participants like Umbaugh are now seeking refunds for their registration fees, with hopes of receiving compensation for the antibiotics they had to take following the event.
