Although the topic hits the newspapers a couple of times a year and Congress holds the occasional hearing, there is little evidence that the issue is on most politicians' or the people's radar screen. Officials at the Centers for Disease Control estimate that one-third of all outpatient antibiotic prescriptions issued in the United States are unnecessary. The World Health Organization puts the figure at 50 percent worldwide. Although antibacterial soaps and cleansers might seem distinct from medicine, the fast-growing use of these products also helps spread resistant strains. And humans are not the only users.
Farm animals consume almost half the antibiotics bought in America.
Only 10 percent of these are used to treat specific illnesses in animals. The rest is added to feed, in low doses, merely as a growth enhancer. In response to this onslaught, bacteria react. By the process of natural selection, those with greater resistance survive and thrive in the presence of antibiotics. And resistance develops not only through random mutations.