CEDAR RAPIDS, Iowa - The number of confirmed cases of cyclospora in Linn County have doubled this week.
However, public health officials said they do not think the intestinal illness is spreading. Rather, awareness about the infection is spreading, leading more people to be tested for the illness.
"We don't think it means there is a lot of continuing exposure," said Patricia Quinlisk, state epidemiologist and medical director at the Iowa Department of Public Health. "We're not sure yet because we don't know what it is (that is causing the illness). We're still recommending people wash off fruits and vegetables the best they can."
There were 10 confirmed cases of cyclospora in Linn County as of Monday. On Friday, the state department of public health announced the number of cases in the county had increased to 21.
The disease, which causes diarrhea, nausea, vomiting, muscle aches and a low-grade fever, in addition to other symptoms, is spread by ingesting food or water that has been contaminated with infected human feces. Those symptoms can last anywhere from nine to 43 days if left untreated.
Quinlisk said that, though young children and the elderly typically experience cyclospora symptoms for a longer period of time, an average healthy adult can experience watery diarrhea for up to 57 days if left untreated.
Most people began experiencing symptoms in mid to late June.
Dr. Stephen Runde, of Mercy Care North in Cedar Rapids, said he has seen a handful of positive cases through their clinic.
"Bactrim DS is the only drug know to work for it," said Runde of the antibiotic being prescribed. "The patients I have had were not allergic to it but if you have an allergy, you're up a creek without a paddle."
At the Linn County Public Health facility, Barbara Chadwick is fielding more calls and questions. Chadwick said people who receive treatment are filling out extensive and detailed diet lists of food they have ingested for weeks.
Quinlisk said a number of factors could have contributed to the case. She said Linn County has a system set up that sends more stool samples to the State Hygienic Lab, which does the testing for cyclospora. Additionally, Linn County has a larger population. She also theorized awareness about the infection has led more people to get tested.
"When we really look at when these people got sick, almost everyone was getting sick in the middle of June, even the people reporting next week," she said.
The disease has hospitalized two people in Linn County. They have been treated, sent home and are recovering, Quinlisk said. She said dehydration causes most of the hospitalizations.
With 45 cases reported in 15 Iowa counties, health officials have more people to interview to determine the source of the infection. Quinlisk said authorities have updated their questionnaire four times and are doing cluster questionnaires to determine if victims have attended the same events in the past two weeks.
"When we do that – these people all came together at this same event," she said. "They all got sick. Then you go down from two weeks to one meal."
That method has allowed officials to narrow down their search from three different events to two, though Quinlisk said they are still "honing in" on the source. However, Quinlisk said public health will likely never identify the source, if it is discovered.
"We don't think any of these places did anything particular, they were just unlucky," she said. "We would never want to blame anybody."
Quinlisk said they believe a contaminated vegetable – rather than a fruit – was the likely cause, though they are still urging people to wash both fruits and vegetables.
She added that, with farmers' markets in full swing, people shouldn't have to worry about buying local produce.
"Most people got sick in the middle of June," she said. "There were very few Iowa fruits and vegetables rip enough to be in a farmers' market in the middle of June. It is highly unlikely it was a fruit or vegetable grown here in Iowa."
Quinlisk said TMP-Sulfa, a common antibiotic, is the only effective treatment for the disease. She said the drug is readily available and works for most people.
"They usually get better within a couple of days," she said.
Reported cases include:
Linn County – 21 cases
Fayette County – 3 cases
Polk County – 3 cases
O'Brien County – 3 cases
Dallas County – 2 cases
Mills County – 2 cases
Webster County – 2 cases
Des Moines County – 2 cases
Benton County – 1 case
Black Hawk County – 1 case
Buchanan – 1 case
Johnson County – 1 case
Pottawattamie County – 1 case
Van Buren County – 1 case
Woodbury – 1 case