DNA tests could link fair, E. coli
Five people who attended the State Fair are suffering E. coli infections that stem from the same genetic strain of bacteria, leading health investigators closer to confirming that a visit to the fair likely led to the outbreak.
A sixth victim who also attended the fair last month in Raleigh got a different strain of the bug, but health officials think the case is still related, health officials said Thursday.
The genetic testing has enabled medical sleuths to rule out at least four cases of E. coli infection that occurred coincidentally to the fair outbreak. Two patients in Mecklenburg County got sick in early October, before the fair opened, and DNA analysis proved that their illness is not connected to the larger outbreak.
Similarly, two other cases were tossed out as coincidental infections. They involve a parent and child who live on a farm and have livestock that probably transmitted the bacteria.
"It's beginning to tighten it up," said Dr. Jeffrey Engel, state epidemiologist. "Every day we get more information. If we can get more DNA types that match the five and they all had fair contact, we almost have a closed case. But we have to wait for results. It just helps us so much in tightening down what the exposure was that got these people ill."
By Thursday, state health officials were investigating 38 cases of E. coli infections. Engel said 75 percent of cases involved children. Three youngsters, including a 13-year-old girl from Moore County and a 2-year-old boy from Wilson, had developed a serious complication known as hemolytic-uremic syndrome, which can cause kidney failure.
The Moore County girl, Katie Maness, was admitted to UNC Hospitals on Wednesday but released the next day. She was able to avoid kidney dialysis, which many patients require.
The number of new cases being reported to state officials has begun to taper off, Engel said, and secondary outbreaks involving human-to-human transmission have not appeared.
As more DNA tests are completed, the investigation will home in on the exact source of the contamination. Two petting zoos worked the State Fair, so figuring out whether either was involved will depend on getting more detailed information from victims and their families about their visits.
Engel said an additional questionnaire will be written this weekend and distributed to families Monday.