Antibiotics fed to livestock may pose a serious health risk to Canadians. A report in Canadian Medical Association Journal suggests high levels of antibiotics are spawning drug-resistant and potentially deadly "superbugs" in humans.

The bugs are passed on to humans when they eat the animals, creating dangerous new infectious diseases.

The Journal says microbial resistance to antibiotics is rising, and so is the use of antibiotics in agriculture. It warns new diseases will emerge unless the commercial use of antibiotics is significantly reduced.

The head of the study recommends new international laws to reduce and eventually eliminate the use of antibiotics for purposes other than human medicine and the treatment of infection in animals.

A Health Canada official responded to the report by saying that farmers will have to change their practices to "minimize the need for antibiotics."

Farmers say they haven't yet seen scientific proof that antibiotics given to animals are causing illness in humans.