The Gaylord Pacific Resort and Convention Center. (Photo by Thomas Murphy / Times of San Diego)

Swimming pools, spas and the water park at the Gaylord Pacific Resort in Chula Vista have reopened in time for Labor Day weekend following a closure due to a parasite found in the water, San Diego County health officials announced.

Last week, the county concluded an investigation into cryptosporidiosis exposure at swimming pools, spas and the water park at the resort, the San Diego County Health and Human Services Agency said Friday.

Guests reported illnesses after visiting the resort’s pools between July 24 and Aug. 15. Three cases were confirmed through laboratory testing, and a fourth was reported by a family member, health officials said.

“The gastrointestinal illness, known as `Crypto,’ is caused by a microscopic, chlorine-tolerant parasite that can trigger gastrointestinal symptoms, including watery diarrhea,” the county said in a statement.

“Symptoms usually start two to 10 days after exposure and last one to two weeks. The resort is private and not publicly accessible, so hotel staff directly notified all guests and day pass visitors who used the pools during the exposure window.”

On Aug. 25, after being alerted by county staff, Gaylord Pacific voluntarily closed all pools and began a CDC-recommended hyperchlorination treatment to eliminate the parasite, according to authorities. The treatment included boosting chlorine levels, inspecting and cleaning pool filters, and maintaining elevated chemical levels until the water met safety standards.

County inspectors visited the resort on Aug. 26, 27 and 28 and verified that proper procedures were completed. All pools, spas and water park features were cleared to reopen on Aug. 28.

For questions about the status of the pool, the public can call the County Pool Program line at 858-505-6900, e-mail fhdutyeh@sdcounty.ca.gov, or call the Gaylord Pacific Resort.

Anyone experiencing severe or worsening symptoms should contact their medical provider or call 211 to receive help in finding care.