(AP) WASHINGTON - The bacon you had for breakfast is at the center of a 35-year debate over antibiotics.
That's because the same life-saving drugs that are prescribed to treat everything from ear infections to tuberculosis in humans also are used to fatten the animals that supply the chicken, beef and pork we eat every day.
Farmers say they have to feed the drugs to animals to keep them healthy and meet America's growing appetite for cheap meat. But public health advocates argue that the practice breeds antibiotic-resistant germs in animals that can cause deadly diseases in humans.
The U.S. government moved to ban the use of some of the drugs in animals in the 1970s, but the rule was never enforced. Then last week, the Food and Drug Administrationfor non-medical purposes over three years.
The U.S., the biggest global consumer of meat by far, follows Europe and other developed nations in restricting the use of penicillin and other antibiotics in animals. The issue has moved to the front burner as documentaries such as "Meet Your Meat" and "Food Inc." have led Americans to focus more on what goes into their food. Sales of antibiotic-free meat, for instance, are up 25 percent to $175 million in the past three years.
"Consumers are beginning to understand the cost of eating cheap meat," said Stephen McDonnell, CEO of Applegate Farms, which markets antibiotic-free meats and cheeses. "As people really understand what it takes to create a healthy animal they will probably eat less meat, but they are going to eat better meat."
Antibiotics have been hailed as one of the greatest medical discoveries of the 20th century since their first use in humans in the 1940s. They've enabled doctors to cure deadly bacterial diseases like tuberculosis, typhoid fever and meningitis.
The FDA approved the use of antibiotics in livestock in the 1950s after studies showed that animals that got the drugs in their feed put on more weight in less time than animals on a traditional diet. For example, pigs that got an antibiotic were shown to need 10 to 15 percent less feed to reach the same weight as pigs on regular diets.
Since feed can account for as much as 70 percent of total animal production costs, the discovery was a windfall for farmers. It meant they could produce more meat for less money, resulting in fatter profits.
But by the 1970s, researchers began warning regulators that routine use of antibiotics was contributing to a surge in drug-resistant germs, or superbugs, that render antibiotics powerless against deadly infections. Professor Stuart Levy of Tufts University conducted the first study in 1976 showing highly-resistant e. coli E. coli bacteria could pass from chickens to farm workers who worked with the animals in just a few weeks.
The study contributed to the FDA's decision to ban nonmedical use of penicillin and tetracycline in farm animals a year later. But farmers and drugmakers pushed back, and the FDA rule was never enforced.
"Why did no one act on it? Because there was a strong lobby," said Levy, who is co-founder and president of the Alliance for Prudent Use of Antibiotics, a nonprofit advocacy group that favors restrictions on the drugs. "They said, `Well, show us the deaths. Show us the real problem. Otherwise, this isn't so terrible."
But it's difficult to link the overuse of antibiotics to deaths. It's tough to find the source of bacteria-resistant germs, which can spread from animals to humans through a number of ways, including undercooked meat and drinking water contaminated by animal waste. And bacteria mutate when passing between species, meaning that the same strain of drug-resistant bacteria in chicken can take on a different form once it enters the human body.
While the issue mostly was tabled in the U.S., it was gaining momentum elsewhere in the world.
In 1999, the European Union backed a ban on penicillin and other human antibiotics for growth in farm animals. Within four years, the use of antibiotics on animals fell 36 percent in Denmark, 45 percent in Norway and 69 percent in Sweden.
Levy, the Tufts University professor, and his colleagues had hoped that the EU's ban would bolster the case for restricting the use of antibiotics in the U.S. But instead, the data has been used to argue both sides of the issue.
U.S. farmers have seized on reports that cases of diarrhea among young pigs increased in the first year after the EU ban, suggesting that animal health had declined. But public health advocates say that the outbreaks among pigs decreased once farmers improved the sanitary conditions by cleaning feedlots more frequently and giving animals more space.
U.S. groups like the National Chicken Council warn that restricting use of antibiotics will result in sicker animals, increasing costs for farmers -- and the price of meat and poultry for consumers. Some industry groups have projected costs for farmers would rise by $1 billion over 10 years, though those estimates have not been backed by outside groups.