I ate it. Then they ate me.
What are the sources of food-borne illness? Granted, you can get sick drinking unpasteurized apple cider or eating sprouted seeds. But much of the problem concerns meat. Salmonella, a major villain in food-borne illnesses, grows in chickens, and ends up in their meat and eggs, as well as in dairy products, red meat, and some veggies. As we've mentioned, at least one strain of E coli, which grows in beef cattle, can be gruesome to your gut.

(Speaking of guts, it's there that most food-borne pathogens reside in animals. Oftentimes, they contaminate the meat during slaughter.)

Most food-borne illnesses are brief, especially for healthy adults. With a good diagnosis, doctors can treat many other infections with antibiotics.

But antibiotics are losing their potency as an increasing number of bacteria become resistant to them. The cause is elementary survival of the fittest. When an animal "takes" antibiotic, the bacteria in its gut die -- except those that happen to be resistant to it. Resistance is a genetic trait, so once a single resistant bug develops, all its offspring will likewise resist that drug (at least while they grow in the presence of the drug).

Resistance arises faster if antibiotics are overused. In many countries, the drugs can be bought without prescription. Even when a doctor's consent is required, they are prescribed for diseases like the common cold, which, being a viral disease, is immune to antibiotics.

Turkey farm practice?
Is antibiotic resistance simply a human problem, or are modern agricultural practices also breeding bugs that "just say no" to the miracle drugs? In 1999, the National Academy of Sciences said that "The use of antibiotics increases the risk of emergence of microorganisms that are resistant to... antibiotics." While holding that medical misuse was a bigger problem, the Academy's experts did substantiate the concern about agricultural antibiotics.

Now we come to the finger-pointing part of the discussion. The animal industry says doctors overprescribe antibiotics, and the medical industry says, in effect, "It takes one to know one." At any rate, a large quantity of antibiotics is used in agriculture. According to the Kansas City Star, 19 million pounds of antibiotics are fed to farm animals each year, and 88 percent of that amount was fed at low doses (see "Livestock Antibiotics... " in the bibliography).

Low doses? Unlike people, many farm animals take antibiotics whether they are sick or not, and for reasons that are only partly related to disease.

A century ago, housing lots of animals in one place amounted to asking for an epidemic, so farmers seldom grew more than 50 chickens in one location. Mark Cook, professor of animal science at University of Wisconsin-Madison, said "With anything more, you'd have a huge risk of losing everything to disease."

When bacteria-fighting drugs became available after World War II, farmers used them, along with vaccination, to control diseases. Today, the two measures can control disease in tightly-packed animal housing, allowing 1 million or more chickens to live in one location.

But antibiotics had a second benefit. Continuously feeding low doses to animals increases the "feed efficiency," the weight added per pound of feed eaten. Higher feed efficiencies cut costs, helping explain why chicken is cheaper than beef.

But it's also risky.

Does routine feeding of low-dose antibiotics turn farm animals into breeding tanks for antibiotic-resistant bacteria?

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