On June 14 the Knox County Health Department (KCHD) lifted a directive it had given Knoxville dairy French Broad Farm nine days earlier to stop distributing raw milk to its shareholders. In Tennessee the distribution of raw milk through herd share agreements is legal by statute. The department had issued the directive because it suspected the dairy was responsible for seven cases (all children) of illnesses caused by the pathogen E. coli O157:H7. The dairy had complied with KCHD’s request and had stopped distributing raw milk on June 5.
The ordeal of the investigation has led the owners of French Broad Farm, Earl and Cheri Cruze, to shut down their herd share operation, a huge loss for the local food community in the Knoxville area. Earl Cruze, 75 years young, has milked cows for 68 years and has always been the only milker for the herd share. Raw milk drinkers in the metro Knoxville area are now out a source of their sustenance.
The department decided to lift the directive, in part, because according to County Health Director Martha Buchanan, “there is no ongoing transmission” of E. coli; the last illness KCHD connected to the dairy occurred on June 3. Buchanan indicated that the department believed that French Broad Farm was the source of the E. coli O157:H7 bacteria that sickened seven children that drank raw milk the farm produced. Interestingly, at the same time the department was investigating the dairy, it had also determined that at least four children had become ill through E. coli O157:H7 poisoning at a daycare center through direct or indirect contact with farm animals. KCHD’s investigation found no connection between the dairy and the daycare center.
What Buchanan or anyone else with KCHD never did explain was why there were no test results from milk and manure samples the department had collected from the farm over a week earlier. KCHD had gone to the farm to take milk samples on June 5 and manure samples on June 6. In addition, the department also collected an unopened container and opened container of raw milk that were produced on the suspect batch dates of May 24 and May 25.
KCHD originally sent the samples to a Tennessee lab but then on June 11 had them transferred to a more sophisticated laboratory in Iowa.
It only takes lab technicians 48 hours to make a preliminary determination on whether a sample is positive for E. coli O157:H7. Typically, if a sample is positive, a health department or other agency will issue a press release announcing the positive test and will continue with its order prohibiting the producer from distributing the suspect food. The likelihood was that all tests the Tennessee and Iowa labs took of the milk and manure samples were negative for E. coli O157:H7; it’s possible that the department didn’t announce any test results because the Iowa lab was still running tests to find e. coli.
Campylobacter, the pathogen most commonly responsible for outbreaks of foodborne illness attributed to raw milk is rarely found in samples tested in a lab; campylobacter grows and disappears quickly. E.coli, including E. coli O157:H7, is different; e. coli will often continue to grow after a sample is taken to a lab for testing. As a result it would be more likely to have a positive test result for e-coli than campylobacter. While all negative test results wouldn’t necessarily clear French Broad Farm of blame for the illnesses, they are evidence that the dairy is not responsible for the E. coli O157:H7 outbreak. The more negative tests the Tennessee and Iowa labs have the greater the evidence the dairy is not responsible for the illnesses. Buchanan did say the department looked for other commonalities among the sick children such as ground beef consumption and swimming pool usage but there are possibly other common activities among the seven children KCHD is unaware of.
Something to look at would be the multi-state foodborne illness outbreak this spring attributed to romaine lettuce contaminated with E. coli O157:H7. There have been five deaths and nearly 200 illnesses in the U.S. blamed on romaine lettuce consumption, including at least three illnesses in Tennessee. From May 16 to June 1, the Centers for Disease Control (CDC) identified an additional 25 cases of illness it blamed on romaine lettuce. Reports are that there is a high level of secondary transmissions from the outbreak.
Earl Cruze ran a Grade A operation, Cruze Farm Dairy, for over thirty years. Cruze Farm Dairy is a completely separate operation from French Broad Farm and is now run by Cruze’s daughter Colleen Cruze Bhatti and son-in-law Manjit Bhatti.
The Tennessee herd share law went into effect in 2009. Since that time, herd share programs have thrived in the state; hundreds of dairies have operated herd shares at one time or another in Tennessee. The French Broad Farm investigation marks the second time herd share operations have been blamed for a foodborne illness outbreak in the state.