The Utah Department of Health and Human Services is urging Utahns to not swim while they have diarrhea to prevent passing cryptosporidium, a parasite that is spread through feces, to others.

There have been 304 Utahns infected with cryptosporidium this summer, a statement issued by the department Tuesday says, and 46 of those cases were reported in the last week. Almost half of the people who got sick, 132, reported that they visited at least one pool or waterpark in Utah in the two weeks before they got sick, and 61 of them reported visiting a lake or other natural body of water.

The most common symptom of cryptosporidium, commonly known as crypto, is watery diarrhea. But the infection can also cause nausea, stomach cramps, vomiting, fever and weight loss.

Release of sporozoites from Cryptosporidium parvum oocyst, 3-D illustration. Cryptosporidium is a protozoan, microscopic parasite, the causative agent of the diarrheal disease cryptosporidiosis.
Release of sporozoites from Cryptosporidium parvum oocyst, 3-D illustration. Cryptosporidium is a protozoan, microscopic parasite, the causative agent of the diarrheal disease cryptosporidiosis. | Kateryna Kon, Shutterstock

The health department's statement says people can get sick after swallowing the parasite in food or water, including while swimming or through contact with infected people or animals. Crypto is the leading cause of disease outbreaks that are linked to recreational water use in the country, the statement says.

The health department suggests that anyone with diarrhea stay out of pools until two weeks after their diarrhea stops, and anyone who suspects they have been infected with crypto should refrain from getting into the water and contact a doctor.

To prevent the spread of crypto, people should wash their hands with soap and water — rather than an alcohol-based hand sanitizer, which does not affect crypto — before eating, after using the bathroom or changing diapers, after contact with animals and after swimming in a pool.

The health department says parents should take children on bathroom breaks or check diapers at least every hour while doing water activities and cautions against changing diapers by the water.

Crypto symptoms begin between two and 10 days after a person is infected, and the symptoms typically last between one and two weeks, the health department says.