As the number of cases doubled Friday from a week earlier, officials said the city water supply would be tested next week as the hunt continues for the source of a parasitic outbreak.

Assistant City Manager Debbie Van Saun said it was unlikely the cryptosporidium outbreak was connected to the city’s water supply. The decision to test was made Friday, she said, because of public concerns.

“We didn’t do it sooner because there was no indication” the parasite was in the water supply, she said.

Kay Kent, director of the Lawrence-Douglas County Health Department, said Friday the number of cases increased to 22, up seven from Thursday’s tally — and double the initial number given Aug. 22. Health officials said they expected the number to continue to increase.

Kent said she did not know whether the new cases were linked to Lawrence swimming pools or how the new cases had been identified.

Also Friday, surveys designed to track the illness’ spread were returned from four randomly selected elementary schools.

“It looks pretty good,” Kent said of the number of returned surveys.

She encouraged parents who had not turned in the forms to fill them out and send them to their children’s school Tuesday.

Cryptosporidium is a microscopic parasite that causes diarrhea, loose or watery stool, stomach cramps, upset stomach and a slight fever. It can be fatal to patients with weakened immune systems, such as the young, elderly or people with HIV. More than two-thirds of those who contract cryptosporidiosis are children.

¢ 6News video: City plans to test water supply¢ Audio clips from city and county officials¢ Parasite outbreak strikes more victims (8-29-03)¢ 6News video: Outbreak spurs search for parasite’s source (8-29-03)¢ Letter to parents (pdf)¢ Questionnaire for parents (pdf)¢ Swimmers flock to pools opened after bacteria scare (8-25-03)¢ Outbreak closes city pools (8-23-03)¢ 6News video: Parasite discovered in city pools¢Centers for Disease Control information

The parasite is easily passed in swimming pools because it is able to survive outside the body for long periods of time and is resistant to levels of chlorine typically found in pools.

Van Saun said the city once regularly tested for cryptosporidium in the water supply, after a 1993 outbreak in Milwaukee sickened 400,000 people and killed 100. There was never any problem found in Lawrence, she said.

“When those results continued to be affirmative (of the water supply’s purity) … we opted to discontinue testing, feeling confident that things were fine,” she said. “We continue to feel confident.”

Cryptosporidium in Lawrence tap water would have sickened far more than the 22 people diagnosed so far, she said. That’s why officials did not rush to begin testing when cases first were confirmed in mid-July.

“If it’s in the drinking water, the results are far more than 11 cases” initially diagnosed, Van Saun said.

The decision to test is “more or less just to allay any fears that people might have,” said Chris Stewart, the city’s water director.

“What I can tell you right now is the regulations are set up to prevent outbreaks of cryptosporidium, if you meet the regulations,” he said. “And what I can tell you right now is we’re far exceeding the regulations.”

Testing raw and treated water from both of the city’s treatment plants will cost $7,800, Stewart said. Assuming a clean bill of health is delivered, the test is expected to be a one-time event.

Any concerns about city water have not shown up in sales of bottled water. Officials at Community Mercantile said Friday their sales of bottled and filtered water had not increased this week.

Amy Turner, an office manager at Lindyspring Water Co., said her office had received a few more calls than usual, but seen no substantial increase in sales.

“Not that I know of,” she said. “We never even heard of it until just a little while ago.”