One of the most important tools of modern medicine is in jeopardy. In the 20th century, antibiotics turned once-lethal infections into manageable diseases. They also contributed to the transformation of meat production in America.
Now, overuse of the drugs in both humans and animals is to blame for the growing threat of antibiotic-resistant bacteria, which the U.S. Centers for Disease Control blames for at least 23,000 deaths a year.
"We are nearly on the brink of being back in the pre-antibiotic era," said Loreen Herwaldt, a University of Iowa professor of infectious disease and internal medicine. "And that's pretty scary, in terms of not having anything to treat people with who have serious infections."