Last week the Food and Drug Administration announced plans to phase out routine use of antibiotics in farm animals, saying the practice produces dangerous drug-resistant bacteria that can infect humans. Farmers have been feeding antibiotics to animals for decades, and the FDA has struggled to curb the practice for at least 35 years. Here are some key dates in the history of the issue:
_1951 The FDA approves the first antibiotics for use in animal feed based on studies showing it helps chickens, pigs and livestock put on extra weight.
_1969 A committee of government experts in the U.K. concludes that the use of antibiotics in animals has contributed to antibiotic resistance in humans.
_ 1970 A U.S. task force, including scientists from the FDA and other agencies, recommends some antibiotics used in humans be banned from use in animals.
_ 1977 The FDA proposes a ban on the use of penicillin and tetracycline in animal feed, unless drugmakers can show the practice is not a danger to humans. The proposal is opposed by farmers, drugmakers and some federal lawmakers. Members of Congress order the FDA to do additional research.
_ 1980 An FDA-commissioned report by the National Academy of Sciences finds little scientific data on antibiotic resistance caused by feeding the drugs to animals. However, the group says that the lack of data is not "proof that the hazards do not exist."
_ 1997 The World Health Organization recommends antibiotics used in humans should not be used to promote growth in animals.
_ 1999 The European Union issues a ban on using popular human antibiotics in animals for growth promotion due to risks to humans.
_ 2003 The U.S. Institute of Medicine issues a report on the rise in dangerous bacteria, or superbugs. The group's recommendations include banning use of antibiotics for growth promotion in animals.
_ January 2012 The FDA orders limits on cephalosporin antibiotics given to animals. The drugs are used to treat pneumonia and other diseases in humans.
_ April 2012 The FDA outlines plans to phase out non-medical uses of more than 200 antibiotics in animals over three years. The voluntary plan requires cooperation by drugmakers and farmers.