Farmers worldwide should take a lesson from Danish bacon producers and reduce the use of antibiotics on their livestock to help stem the growth of drug-resistant bacteria in humans, the U.N. health agency said Wednesday.
The World Health Organization said a panel of experts had studied a landmark program in Denmark - the world's largest exporter of pork - which in 1998 imposed a voluntary ban on the use of the drugs, also know as antimicrobials, to boost animal growth.
WHO has said overuse of drugs for purposes other than treating animal disease is partly behind a rise in the number of resistant bacteria found in livestock. The agency fears such bacteria can be transmitted to humans who eat affected meat.
High-profile scares over the transmission of resistant forms of bacteria - such as salmonella - have become increasingly frequent, particularly in Europe. WHO noted that most resistant bacteria growth among humans was due to overuse of antibiotics by doctors - not due to farmers.
But, in a 58-page report, WHO said the Danish ban had been effective in reducing the spread among food animals.
"This program has been very beneficial in reducing microbial resistance in important food animal (stock)," WHO said. "This reduces the threat of resistance to public health."
Farmers in many rich countries use antibiotics not only to treat sick livestock but also because the drugs boost an animal's growth when added to feed in low, "sub-therapeutic" doses. Some growth promoters belong to groups of drugs that are essential in human medicine for the treatment of serious, potentially life-threatening, bacterial diseases, such as staphylococcus or enterococcus infections.
In Denmark, use of antibiotics in animal feed dropped by 54 percent after the ban, which also applied to poultry. In parallel, WHO said, the percentage of Danish livestock with resistant bacteria fell "dramatically" - from as high as 80 percent to as little as 5 percent, the study found.
Cutting out antibiotics raised Danish farmers' costs by 1 percent - or around euro1 (US$1) per pig - but this appeared to be offset by increased consumer confidence and the likely human health benefits, said WHO.
"Under conditions similar to those found in Denmark, the use of antimicrobials for the sole purpose of growth promotion can be discontinued," the agency said.