The controversy over the effects on human health of widespread use of antibiotics in livestock continues. At the end of 2011, the Food and Drug Administration (FDA) recommended the phasing out of this practice, beginning in April 2012, long used by farmers to promote faster growth in food-producing animals such as cattle, pigs, and poultry. Called “nontherapeutic antibiotics,” the drugs were often touted by livestock producers as a way to decrease illness in animals raised in overcrowded housing and stressed by truck hauls to the slaughterhouse. But the health benefits to the animal were never proved in scientific studies and factory farming was likely the biggest threat to the animals’ health. Many studies have furthermore found that nontherapeutic antibiotics have contributed to the rise of antibiotic resistance in microbes that infect humans.

FDA’s main target is the antibiotic class called cephalosprins. These drugs have become a backup line of defense in the treatment of human infections resistant to earlier generations of antibiotics, such as penicillins. Some microbiologists applaud the FDA’s step, but others feel it doesn’t go far enough because many of the recommendations to cut back on antibiotic use are voluntary. Successful strategies for reversing the tide of antibiotic resistance have been difficult to find. As long as we continue widespread use of antibiotics, expect widespread occurrence of antibiotic-resistant germs.