FORT WORTH -- Tarrant County Health officials said Friday that "hundreds of people" have contacted them with concerns that they contracted a water-borne parasite, which officials say was possibly spread at a popular Fort Worth swimming hole.
At least eight people were diagnosed with the cryptosporidiosis -- also known as "crypto" -- and Burger's Lake may have been the source, officials announced Thursday.
The lake's owners voluntarily closed the spring-fed lake Thursday as health officials awaited the results of water tests. The results are expected Saturday.
Since the announcement, the health department's phones have rung steadily, said Vanassa Joseph, a county health spokeswoman. The department's epidemiology staff is using a questionnaire to determine whether the callers have symptoms.
Never miss a local story.
"I had a gentlemen call this morning who said he had been out there in a group of nine and some got sick and some didn't," Joseph said. "We're getting their names and phone numbers."
The parasite that causes crypto is found in human and animal fecal matter. It thrives in bodies of water and is resistant to chlorine disinfection.
Symptoms include abdominal pain, diarrhea, loss of appetite, nausea and vomiting. Dehydration can occur in young children, pregnant women and other vulnerable groups.
Anyone who visited the lake after June 21 and became ill should seek medical care, said Anita Kurian, epidemiology division manager for Tarrant County Public Health. Physicians will contact the health agency.
The symptoms are not pretty, said those who believe they were sickened.
"I have been sick, sick, sick," said Crystal Bailey, 25, of Dallas, who visited the lake during the July 4 weekend and started feeling sick Sunday. "I couldn't even go to work."
Exposed people who go swimming could spread the parasite for up to two weeks after symptoms have stopped, Kurian said.
"Our main concern is that individuals who get sick may transmit it to others in the community," she said.
Isolated clusters of the illness have been seen in Tarrant County over the years, but nothing of this magnitude, health officials said. They don't know how many people may be infected.
About 275 crypto cases a year are reported in Texas, and they are usually small-scale, said Doug McBride, a spokesman for the Texas Department of State Health Services.
"It's sporadic -- one case here and one case there," he said. "We haven't had any recent outbreaks."
Signs posted outside the lake Thursday read, "Burger's Lake is closed and will reopen upon further notice." A recorded telephone message said the same thing. The owner could not be reached for comment.
The illness came to the attention of health officials early this month after physicians started reporting the symptoms. But it's a mystery as to how it got started, Kurian said.
"Did people come to Burger's Lake and get infected? Or did they bring it to Burger's Lake?" she said.
Burger's Lake is a 1-acre spring-fed lake in a 30-acre park. It includes two beaches, diving boards, a 20-foot slide and lifeguards. Health officials said it appeared to be well-maintained.
As the temperature reached 95 degrees at noon Thursday, a steady stream of cars and trucks carrying families in swimsuits stopped briefly at the locked gates and then drove away.
Scott Chilton, who swam at the lake as a child, arrived with his 7-year-old son, 9-year-old nephew and a stack of beach towels.
"I liked it a lot when I was young," he said, adding that he wanted his son to see it. "Guess we picked the wrong day for it."
Some self-described regular visitors said they hope the illness doesn't keep people from coming to the lake after it is resolved. The facility is clean and well-run, they said.
"I like this place; it's great," Jeff Rankin said. "But if something's wrong, I'm sure they'll take care of it."