You are no doubt aware of the recent outbreak of food poisoning coming from fresh spinach. At least 100 people have become infected and at least one has died. The culprit in this infectious disease is a type of E. coli, a common bacteria found in our own GI tracts as well as in GI tracts throughout the animal kingdom. The particular bacteria causing this recent nasty outbreak is a strain called E. coli O157:H7.
Health officials nationwide are hot on the trail of this E. coli strain, trying to track down which spinach growers, shippers, and/or packagers are responsible for foisting this plague off on the rest of us. As an editorial in today’s New York Times points out, however, they are totally on the wrong trail.
We all have our own strains of E. coli in our own GI tracts that we live with in peaceful co-existance. When we get a dose of someone else’s E. coli, as long as they are a friendly strain, we do okay. When we get a dose of a foreign E. coli such as the strain found commonly in Mexico, for example, we often end up with a case of Montezuma’s Revenge that makes us miserable for the first few days after we get home.
The acidity of our own stomachs can usually wipe out a dose of normal E. coli that we pick up eating food that has been handled with (I got this from a medical school microbiology lecture, and it has stuck with me since) the freshly fecaled fingers of food servers or fruit and vegetable pickers. (That’s why your mother always told you to wash that apple before you ate it.) But the O157:H7 strain is a little different.
Your stomach juices are not strong enough to kill this acid-loving bacterium, which is why it’s more likely than other members of the E. coli family to produce abdominal cramps, diarrhea, fever and, in rare cases, fatal kidney failure.
This particularly virulent strain of E. coli comes from the GI tracts of cattle that have been fattened with grain–particularly corn–instead of grass or other silage. Grains and corn are not the natural foods of cattle, and when cattle are fed nothing but in an effort to fatten them, they develop highly acidic GI tracts. The E. coli O157:H7 is a strain that has evolved to live in this highly acidic environment, and, consequently, is immune to the acid in our own stomachs that is typically potent enough to knock out the regular garden-variety E. coli we most often encounter.
Beef cattle are not the only carriers of the O157 strain.
In 2003, The Journal of Dairy Science noted that up to 80 percent of dairy cattle carry O157. (Fortunately, food safety measures prevent contaminated fecal matter from getting into most of our food most of the time.)
As anyone who has been around cows of any variety knows, they defecate prodigiously. In the case of beef cattle and dairy cattle that have been corn fed, these patties are teeming with O157:H7, which can contaminate all kinds of things it comes into contact with, including the groundwater. As long as cattle continue to be corn fed, we continue to produce massive amounts of this virultent strain that will continue to find its way into water and other foods. In the case of the spinach, who knows? It could have been irrigated with water infected with O157:H7 from run off from a nearby feedlot.
How do we know that the next time we buy celery or lettuce that we won’t get a dose of O157:H7? We don’t, and unless we do something about the source of the problem, we run this risk more and more.
According to the above mentioned Journal of Dairy Science there is a solution.
When cows were switched from a grain diet to hay for only five days, O157 declined 1,000-fold.
And as the Times points out
In a week, we could choke O157 from its favorite home — even if beef cattle were switched to a forage diet just seven days before slaughter, it would greatly reduce cross-contamination by manure of, say, hamburger in meat-packing plants. Such a measure might have prevented the E. coli outbreak that plagued the Jack in the Box fast food chain in 1993.
Because of the growing demand for grass-fed beef, more and more ranchers are opting to let their cattle graze, but we are a long way from the demise of the feedlot. As consumers we can do our part by voting with our dollars. Buy grass-fed beef everychance you get. If enough people insist, it will be better for us, the cows and the environment. The only losers as far as I can see would be the E. coli O157:H7.
Here is a great website telling you everything you need to know about grass-fed beef, including where to find it in your neck of the woods. Take your dollars and get out there and vote.