The Tennessee Department of Health has announced that the strain of E. coli O157:H7 that sickened nine children has been matched to animal waste collected at the McBee dairy farm in Mascot, Tennessee that produced the milk. This is a DNA match that proves that the pathogenic bacteria that made the children sick came from the farm.
Five of the nine children sickened in this outbreak were hospitalized. Three of them developed hemolytic uremic syndrome (HUS), a serious complication of a shiga toxin-producting E. coli bacteria that can cause kidney failure, strokes, seizures, and death.
The investigation conducted by public health officials included an on-site inspection of the farm, interviews of the 88 households that purchased milk from the farm, and lab analysis of milk and other product samples and materials to compare bacteria strains. TDH Commissioner Dr. John Dreyzehner said in a statement, “this outbreak points out, again, the serious risks associated with drinking unpasteurized or ‘raw’ milk. While people with stronger immune systems may be able to overcome the bacteria found in raw milk, children, older people, pregnant women and those with health conditions can be seriously harmed by bacteria in non-pasteurized milk products and should not consume them.”
It’s difficult to test milk for pathogenic bacteria, since the bacteria are usually present in tiny clusters that clump together. That means that if there are pathogenic bacteria in the milk, they are difficult to find and there may be none in the small tested samples. It only takes 10 E. coli O157:H7 bacteria to make someone seriously ill. For comparison, up to 500,000 bacteria can fit on the tiny period at the end of this sentence.
State Epidemiologist Dr. Tim Jones said about this outbreak, “milk from the healthiest-appearing cows in the cleanest dairy operations can still contain deadly microorganisms. Pasteurization, which simply involves heating the milk, kills these microorganisms and leaves the healthy nutrients. Those who consume raw milk are playing Russian roulette with their health; the glass they drink today may not have deadly microorganisms, but the one they drink tomorrow may cause serious health problems or even death.”
Even though food safety is being taught more and being required by laws to be taught to those who prepare it, hard headed people will always be hard headed people. Not much that you can do about that.