06/08/2026
Some of the most common diarrhea-causing germs associated with recreational water illnesses include Cryptosporidium (Crypto), Giardia, Shigella, norovirus, and E. coli O157:H7. According to the CDC, even in properly chlorinated water, these germs can survive anywhere from a minute to several days. An individual can become sick from ingesting a small amount of contaminated water. Symptoms vary by the type of recreational water illness, but often include stomach cramps, nausea, watery diarrhea, vomiting, and fever. In severe cases, like with Cryptosporidium infections, the illness can become life-threatening, especially amongst vulnerable populations such as children, pregnant people, and immunosuppressed individuals.
Local health departments play an important role in keeping swimmers and aquatic facilities safe. Through communication campaigns and local outreach, LHDs can educate the public on the dangers associated with swimming with diarrhea and highlight the importance of staying out of the water while sick. If an outbreak occurs, LHDs can disseminate closure notices and share guidance on symptoms associated with the outbreak. Routine inspections of aquatic facilities help ensure local facilities follow safety practices that prevent diarrheal illness outbreaks.
https://www.cdc.gov/healthy-swimming/prevention/index.html
