After two confirmed cases of Cryptosporidium, Foss Swim School is closing their St. Louis Park and St. Paul locations for two weeks as a precaution.

ST. LOUIS PARK, Minn. — Foss Swim School announced Tuesday it has closed its St. Louis Park pool for the next two weeks after two swimmers - a teacher and a student - contracted Cryptosporidium, a parasite that causes diarrhea.

Foss later released a statement that they would also be closing their St. Paul location after they discovered the teacher had also taught there as well.

"We do not know if Cryptosporidium has ever been in our pool," the school told parents in an email. "We do not know the source of the two cases. This two-week closure will enable us all to wait out the incubation period of Cryptosporidium."

The St. Louis Park pool will be drained and equipment will be replaced before it reopens around Oct. 15, according to the email.

The St. Louis Park pool has been cleaned twice since Sept. 20, when the school reported the first case to the Hennepin County Department of Health. Parents were not notified about the Cryptosporidium until this week; the swim school said it followed all protocol and waited to send details of the disease until it became apparent the first case was not isolated.

"I would not have taken my daughter to swimming lessons," parent Cassie Bonstrom said, wondering why it took so long to learn details about the parasite. "We would have skipped the week."

In the email to parents this week, the school said "your child's safety is of my utmost concern and I apologize that you were not informed sooner around this issue."

"Stuff like this just happens, but how you handle it is really important," Bonstrom said. "And, I wish I would have known earlier."

Trisha Robinson, the head of the MDH waterborne disease unit, said an investigation is ongoing -- and it's likely there are more than two cases.

"We have identified some other people who are sick as well," Robinson said.

Minnesota typically sees 300 to 500 cases of Cryptosporidium each year, with a high of 532 reported in 2018. It spreads when sick swimmers ignore their symptoms.

"That's the way it's getting into our water, so we have to get people to change their behavior," Robinson said, "and get people out of the water when they're sick."

While the St. Louis Park location remains closed, Foss Swim School will credit parents for any missed swimming classes. The St. Paul location will be closed Oct. 2 -16.

The Minnesota Department of Health (MDH) announced on Oct. 8 that it is investigating reports of diarrheal illness caused by Cryptosporidium among those who swam at the Foss Swim School location in St. Paul.

The department is urging individuals - whether they have been sick or not - to fill out a brief survey if they swam at the St. Paul location.