The strain of E. coli that caused nine children to become ill in Tennessee has been traced to raw milk from the McBee Dairy Farm near Knoxville and samples from the milk matched samples of animal waste taken at the farm, the Tennessee Department of Health has announced.

The sickened children are all younger than seven. Five of them were hospitalized and three developed a serious kidney condition, called hemolytic uremic syndrome, as a result of consuming the contaminated raw milk.

The state's department of health said that the investigation included an inspection of the farm and interviews with all 88 households that purchased milk from McBee Dairy Farm. Officials from the Knox County Health Department also took part in the investigation, the statement said.

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John Dreyzehner, Tennessee Department of Health commissioner, commented that the E. coli outbreak highlighted the serious health risks associated with raw milk consumption. Milk that has not been pasteurized can be very dangerous because it can be contaminated with different strains of bacteria. The consequences can be grave for children, pregnant women and elderly people, he pointed out.

Tim Jones, state epidemiologist at the department, added that pasteurization is a process that just kills the harmful bacteria without taking away any of the health benefits of the product and he strongly advised against consuming raw milk even if it comes from cows that look healthy and from dairy farms that have the cleanest operations.