The Knox County Health Department (KCHD) continues to investigate a cluster of Escherichia coli (E. coli) 0157 infections in children. While all potential sources remain under investigation, the evidence continues to suggest the cases are associated with two probable sources: consumption of raw milk and contact, either direct or indirect, with farm animals. KCHD is investigating any potential connections between these two likely sources. However, while it would be rare, it is possible these are two unrelated E. coli clusters occurring at the same time.
Following epidemiological standards and methodology, the health department’s ongoing investigation has included conducting extensive interviews with the families of the ill children; contacting persons who may be at risk to see if anyone in the household is ill; examining all potential sources; plotting symptom onset to aid in determining the first case, potential exposures and the type of outbreak; analyzing the statistical significance of the findings; and collecting samples from both sites. Samples collected from the farm and child care facility are still being analyzed. In these situations, public health laboratories not only culture the samples for the pathogen in question, E. coli 0157 in this case, they also conduct a more in-depth analysis that can reveal the exact genetic fingerprint of the strain of E. coli 0157. While samples are a part of due diligence in a disease investigation, they are just one piece of the overall evidence.
Both Kids Place, Inc., Mascot, Tenn., and French Broad Farm, Knox County, Tenn., have fully cooperated throughout KCHD’s investigation, including sharing contact information of those who may be at risk, supporting sample collection and ceasing operations as requested. At this point in the investigation and in light of the fact that there is no ongoing transmission, KCHD is lifting the health directive requesting French Broad Farm temporarily cease operations. While the investigation thus far has revealed no specific problems with French Broad Farm, the risk in consuming raw milk cannot be mitigated. Even with safety precautions in place at a dairy and adherence to the strictest dairying procedures, there is no way to ensure raw milk, while legal, is safe for consumption. This is why health officials recommend the public consume only pasteurized milk and dairy products.
KCHD lifted the directive for Kids Place, Inc. on Friday, June 8, 2018. By following existing state and national procedures for infection control and mitigation at a permitted, regulated facility, the risk at Kids Place, Inc. has been mitigated.
E. coli 0157 can cause disease by making a Shiga toxin; these are referred to as Shiga toxin-producing E. coli or STEC. This can cause severe diarrhea and even life-threatening complications, especially in children, older adults, pregnant women and those with compromised immune systems. Approximately 5 to 10 percent of those diagnosed with a STEC infection develop a potentially life-threatening complication known as hemolytic uremic syndrome (HUS). Clues that a person is developing HUS include decreased frequency of urination, feeling very tired, and losing pink color in cheeks and inside the lower eyelids. Persons with HUS should be hospitalized because their kidneys may stop working and they may develop other serious problems.
Raw milk and other unpasteurized products can contain harmful bacteria, including E. coli 0157. While it is possible to get sick from many other foods, raw milk is one of the riskiest. As stated in the American Academy of Pediatrics policy statement on unpasteurized dairy, only an estimated 1 to 3 percent of dairy products consumed in the U.S. are unpasteurized. Yet these products account for 82 percent of the milk- or milk product-associated foodborne outbreaks reported to the Centers for Disease Control and Prevention between 1973 and 2009.
E. coli can also be found in the feces of cattle, goats, sheep and other ruminant animals. Historically, the major source for human illness is cattle, which can carry E. coli 0157 but show no signs of illness. E. coli can also be spread person-to-person through the fecal-oral route, which is why adequate handwashing is crucial in preventing the bacteria from spreading to others. More information on preventing E. coli can be found on the CDC’s website.
Symptoms of E. coli infection vary for each person, but often include severe stomach cramps, diarrhea (often bloody) and vomiting. Some may have a low fever (less than 101˚F). Some infections are mild, but others can be severe. Seek medical attention immediately if you or your child has diarrhea lasting more than two days or contains blood. Tell your provider if you or your child have consumed raw milk or had contact with farm animals.