Published Date: 2012-01-22 12:47:58
Subject: PRO/AH/EDR> E. coli EHEC, 2011 - USA: (CA), raw milk, environmental source
Archive Number: 20120122.1017852
E. COLI EHEC, 2011 - USA: (CALIFORNIA), RAW MILK, ENVIRONMENTAL SOURCE
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Fri 20 Jan 2012
Source: CBS News [edited]
Environmental samples collected from a Central California raw milk dairy's calf area tested positive for the strain of _Escherichia coli_ that infected 5 children last year, according to a letter from California health officials made public on Friday 20 Jan 2012.
In the letter to Organic Pastures Dairy Co. owner Mark McAfee, the California Department of Public Health said 10 of the samples taken from manure, soil, water, and work surfaces at the Fresno County dairy tested positive for _E. coli_ with a genetic pattern indistinguishable from the outbreak strain.
"The fact that _E. coli_ O157:H7 identical to the outbreak strain was recovered from OPDC environmental supports the probability that the OPDC raw milk that the case patients consumed was similarly contaminated leading to their illnesses," wrote Patrick Kennelly, chief of the health department's food safety branch. California officials recalled and quarantined the dairy's raw milk products in November 2011 after 3 children who drank Organic Pastures milk were hospitalized. But officials did not find _E. coli_ in either the company's recalled products or the bottles taken from the homes of the sickened children, and the recall and quarantine were lifted in December 2011.
"Cows' stool is the most common reservoir of _E. coli_ O157:H7 and it does not cause cows illness," said Bill Marler, a Seattle-based food safety lawyer. "The problem for Organic Pastures is that they not only found 10 samples that were positive for _E. coli_ but also found two samples that were a genetic fingerprint match to the ill children. That strain is a unique strain, and it helps tie the fact that the most likely source of the children's illnesses came from the farm."
Organic Pastures chief operating officer Aaron McAfee said the dairy accepts the health department's findings but remains confused about how the bacteria made it from the calf area to consumers when no milk products were found to be contaminated, and samples taken from the area where cows are milked also tested clean. Adding to the mystery is the fact that the dairy was not raising calves during the period from August to October 2011 when the children fell ill, McAfee said.
The company since has instituted even stricter food safety procedures, he said [but not pasteurization - Mod. LL].
Raw milk enthusiasts say pasteurization kills bacteria beneficial to human health and argue that raw milk is medicinal and can treat everything from asthma to autism.
The Centers for Disease Control and Prevention (CDC), however, warns that raw milk can cause illness or death, with infants, the elderly, pregnant women and those with weak immune systems especially vulnerable. From 1998 through 2008, CDC reported 1676 illnesses due to consumption of raw milk or raw milk products. No deaths were reported.
[This follow-up to a November 2011 outbreak of _E. coli O157 associated with unpasteurized milk illustrates the limitations of culture in showing that the alleged vehicle is or is not "smoking", that is, has isolated from it the genetically identical cluster strain. The strain now has been shown to be present on the facility, res ipsa loquitor - the thing speaks for itself. - Mod.LL
A HealthMap/ProMED-mail map can be accessed at: http://healthmap.org/r/1hcv, http://healthmap.org/r/1kJo.]