This is an issue I have been pushing for some time because it amounts to a genuine and widespread health hazard. To quote the Union of Concerned Scientists:

Antibiotic-resistant bacteria are on the rise. Patients once effectively treated for pneumonia, tuberculosis, or ear infections may now have to try three or more antibiotics before they find one that works. And as more bacterial strains develop resistance, more people will die because effective antibiotics are not identified quickly enough or because the bacteria causing the disease are resistant to all available antibiotics.

Why have bacterial strains become resistant? The short answer is overuse of antibiotics. Physicians and hospitals have overprescribed the drugs, and patients have demanded them—even for illnesses not caused by bacteria. Veterinarians, too, overprescribe drugs to treat sick animals.

It is livestock producers, however, who use the vast majority of antibiotics produced in the United States. An estimated 70 percent of antibiotics and related drugs produced in this country are used for nontherapeutic purposes such as accelerating animal growth and compensating for overcrowded and unsanitary conditions on large-scale confinement facilities known as "factory farms." This translates to about 25 million pounds of antibiotics and related drugs fed every year to livestock for nontherapeutic purposes—almost eight times the amount given to humans to treat disease.
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