05 July 2011

Drug resistant E. coli possibly caused by antibiotic use in chickens

A recent paper published in the Centers for Disease Control and Prevention (CDC) journal, Emerging Infectious Diseases, is claiming the drug resistant genes in E. coli carried by chickens and E. coli infecting humans, are so alike they believe that chickens may be the cause.

The authors of the paper (a joint affair between several Dutch hospitals, the Heart of England National Health Service Foundation Trust, University of Birmingham and the National Institute of Public Health and Environmental Protection in the Netherlands) compared E. coli strains taken from hospital patients (swab specimens), strains taken from randomly chosen supermarket meat, and E. coli blood cultures taken from patients in the hospitals – all the samples were taken in the same time period. The aim of the comparison was to see whether all strains tested had the antibiotic resistant genes known as ESBL, or Extended-Spectrum Beta-Lactamase.

After testing all the samples, they found that:

  • 5% of the patients contained ESBL genes.
  • Of the blood cultures, 74% had ESBL genes.
  • 30% of the meat samples harbored the gene. 
  • Of the 30% that harbored the gene, ESBL was found in 80% of the chicken samples, 5% of the beef, 2% of the pork, and 9% of ground and mixed meat.

After using genetic analysis it was determined that the genes present in the chicken meat and in the human swab specimens were identical.

This is not the first time such correlations have been found between antibiotic use in animals and antibiotic resistance in humans and to a lot of people there is no surprise in the findings. Antibiotics are routinely used in mass meat and milk production to ensure livestock avoid diseases which can be caused by being in such close proximity to each other, plus it helps the animal grow faster which increases yield to the producer in less time.

For several decades, scientists have been concerned with bacteria becoming resistant to antibiotics commonly used in factory farms, which has led to the practice being banned in the European Union, and the World Health Organization (WHO) recommending that all countries should stop the use of antibiotics as growth promoters. The U.S. Food and Drug Administration (FDA) issued guidelines to the livestock industry, but the recommendations were voluntary.

The farming industry maintains that the use of drugs is necessary to prevent disease, but it seems ludicrous that a practice that can potentially harm so many people is being ignored to protect the profits of the animal agriculture industry. Isn’t it time that the FDA bit the bullet and introduced obligatory withdrawal of antibiotic use in agriculture?

Bev Hahler | @redhotvegan
Bev, a vegetarian since she was 14 years old, became more interested in veganism several years ago after studying Agro-business as part of an Ecology degree. She has a gorgeous daughter in second grade who has been a vegetarian her whole life (lucky girl). Follow Bev on her blog and Facebook.

Photo credit:cc:flickr.com/photos/lollyknit