The following is excerpted from an editorial published in the November 2006 issue of The Journal of Infectious Diseases (2006;194:1191–1193)addressing concerns related to antibiotic resistance and calling for a complete ban of subtherapeutic antibiotics use in food animals. The editorial accompanies a research article in the same issue of the Journal that reveals new evidence showing poultry fed antibiotics contribute to antibiotic resistant bacteria in humans.  (See previous post.)
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DOI: 10.1086/508221
EDITORIAL COMMENTARY
Food Safety Revisited
Niels Frimodt‐Møller and
Anette M. Hammerum

National Center for Antimicrobials and Infection Control, Statens Serum Institut, Copenhagen, Denmark

Antibiotic growth promoters have been an issue in Europe since the early 1990s, and European investigators have expended a great deal of effort in elucidating the risk for humans of using antibiotic growth promoters on such a broad scale as was the case in Europe, where almost all feeds sold on the market contained some antibiotic growth promoter. Most research has focused on vancomycin‐resistant E. faecium (VRE) and/or streptogramin‐resistant E. faecium (SRE); in some cases, the bacteria have been resistant to both groups of antibiotics. With the use in feed of avoparcin or virginiamycin (the glycopeptide and streptogramin used in animal husbandry), VRE or SRE was selected [15], and there was a high prevalence of VRE or SRE in poultry before and at slaughter [16], the farms were constantly contaminated, and VRE and SRE spread to new flocks [17], VRE was found in poultry meat in food stores [18], and there was a prevalence of up to 20% of VRE in feces from nonhospitalized European individuals [19]. VRE from human infections showed the same PFGE types as strains found in pigs [20, 21]. In addition, VRE and SRE (from poultry and pigs) in milk ingested by volunteers survived the acidity of the stomach and reached the gut, multiplied, and remained there for 14 days [22], and VRE and SRE transconjugants could be detected in feces 2 days after the ingestion of both a VRE/SRE donor strain and a recipient E. faecium strain in human volunteers without antibiotic treatment [23]. The final worrying step in the risk chain was provided by the report from Michigan several years ago about the isolation from a patient of a vancomycin‐resistant Staphylococcus aureus containing the vanA element from E. faecalis [24]. More evidence that antibiotic growth promoters confer resistance has now been provided [14].

The answer for the SRE and VRE is easy: ban antibiotic growth promoters! This has worked in Europe without serious consequences for the well‐being of the animals, their breeders, or consumers [25]. In Denmark, isolation of VRE and SRE has been greatly reduced over the past 10 years. VRE and SRE are still present in the poultry flocks, albeit in lower numbers, but they can be found with selective enrichment methods [26]. This means that VRE and SRE are still present and that the reintroduction of growth promoters would easily increase the level of resistant bacteria in poultry flocks.

References

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