More on antibiotic use in animal rearing

I wrote last month, suggesting that it is high time we banned the sub-therapeutic use of antibiotics currently used in human therapy for animal rearing. 

When I wrote the article, I was not aware that the Food and Drug Administration had, around 9th November 2011, rejected two petitions to ban antibiotics from being used in food animal production. The petitions were filed by a coalition that included  the American Public Health Association and the Union of Concerned Scientists.

It is troubling that in its denial letter, the FDA acknowledged that its “experience with contested, formal withdrawal proceedings is that the process can consume extensive periods of time and agency resources.”  I interpret that to mean that FDA may well think that antibiotic use should be banned, but it can't afford to force the issue.

Meanwhile, researchers at McGill University have shown that bacteria resistant to tetracycline and tylosin can be isolated from pigs raised in a swine complex 2.5 years after administration of these antibiotics ceased.  See Microbial Ecology  DOI 10.1007/s00248-011-9954-0  published on-line 14th October 2011.  Antibiotic resistance genes were found in the bacteria, though the workers were not able to explain their persistence long after antibiotic use ceased.  The results are of significance for both animal and public health because these antibiotic resistant bacteria can be transferred between animals, humans and the environment.