Animal use-human resistance link still unclear

About 700,000 people die each year when they are infected with diseases that cannot be cured with antibiotics.

Antimicrobial resistance is recognized globally as an impeding crisis, and often the use of these products to treat livestock is blamed for increasing the antibiotic resistant bacteria population.

It is not known whether restricting the use of antibiotics in animals will lead to a decrease in antimicrobial resistant bacteria in humans, said Herman Barkema of the University of Calgary’s faculty of veterinary medicine.

While organizations such as the United Nations’ Food and Agriculture Organization recommend reduced use and upgraded farm management, these suggestions are more of an ideal than a practical approach, especially in developing countries, he said at the recent World Animal Production Conference held in Vancouver.

There is a high level of management in Canada, the United States and Europe with well-trained farmers and veterinarians who can prevent or control infections.

However, controlling infection is more difficult in some developing countries where conditions are less than ideal.

“There is a lot of extra label use everywhere in the livestock industry. It is common practice, often because no veterinarians are around,” he said.

“If we stop using antibiotics in those countries, we are jeopardizing their protein sources.”

Almost no studies have been done on what happens when antibiotic use is reduced, so he joined a broad study to review current research.

The review was challenging because there is almost no information from China, Africa and India.

It is estimated that 63,150 tonnes of antimicrobials were used to treat livestock worldwide in 2010. That is expected to increase by 67 percent in 2030.

The FAO’s Action Plan on Antimicrobial Resistance report estimated that future growth of antimicrobial use is expected to occur within the animal production sector with use in pig and poultry production predicted to double.

The FAO also said the availability and use of antimicrobial drugs for livestock and in-crop production are essential to both health and productivity. They contribute to food security, food safety and animal welfare and protect livelihoods and the sustainability of animal and crop production.

Barkema’s recommendations include:

  • banning the use of growth promoters, particularly in the developed world
  • banning the livestock use of all antimicrobials essential for human health
  • developing clear and quantitative goals to reduce the overall use of antimicrobials

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