To the Editor:

Re “Resistant Bacteria in Meat” (letter, nytimes.com, April 24):

As the main force behind the effort to limit antibiotic use in food animals, I am astonished by the letter from Bernadette Dunham, the director of the Food and Drug Administration’s Center for Veterinary Medicine, especially since she told a House committee on April 9 that she was unsure how antibiotic resistance develops.

The F.D.A. itself said in 1977 that feeding antibiotics, one of medicine’s greatest breakthroughs, to farm animals indiscriminately was dangerous to human health. Evidence on this is so clear that the American Medical Association, the World Health Organization, the Union of Concerned Scientists and 450 groups support my legislation to save eight classes of antibiotics for human health.

Scientists say strep throat could soon prove fatal. Everly Macario, a doctor in public health who lost her 18-month-old son to a MRSA infection, said it best: “I don’t know why people aren’t freaking out about the fact that we’re nearly at a post-antibiotic era.” The F.D.A., tasked with protecting the public’s health, should understand that, given the 70,000 deaths a year that are due to antibiotic-resistant infections.

LOUISE M. SLAUGHTER

Washington, April 25, 2013

The writer, a microbiologist, represents New York’s 25th District in the House.