High Levels of Resistant Bacteria on Meat (Again)

A new report is out from the federal collaboration that monitors antibiotic resistance in animals, retail meat and people, and the news is not good.

The full title is the 2010 Retail Meat Report from the National Antimicrobial Resistance Monitoring System. This report is issued by the Food and Drug Administration; the humans one comes from the Centers for Disease Control and Prevention and the animals one from the US Department of Agriculture. It reports the results of testing on 5,280 meat samples collected in 2010 in California, Colorado, Connecticut, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon, Tennessee, and Pennsylvania. (Those are sites of state labs participating in a federal surveillance network, FoodNet, plus one volunteer lab, Maryland.)

The report — which is broken down first by foodborne organism and then by meat type — notes a number of instances where either the percentage of bacteria that are antibiotic resistant, or the complexity of the resistance, is rising. Quoting from the report:

For Salmonella:

• Third-generation cephalosporin resistance rose in chicken breast (10–34.5%) and ground turkey (8.1–16.3%) isolates from 2002 to 2010.
• There were significant increases in ampicillin resistance among chicken breast (16.7–39.2%) and ground turkey isolates (16.2–48%).
• 43.3% of chicken breast isolates were resistant to ≥ 3 antimicrobial classes in 2010 compared to 33.7% in ground turkey.
• More than 29% of chicken breast isolates showed resistance to ≥ 5 classes in 2010.

For Campylobacter:

• Ciprofloxacin resistance in C. coli from chicken breast rose from 10% in 2002 to its highest peak of 29.1% in 2005.
• Since the fluoroquinolone ban in September 2005, ciprofloxacin resistance in C. coli has decreased to 13.5% in 2010, while resistance in C. jejuni significantly increased from 15.2–22.5% from 2002 to 2010.
• Gentamicin resistance in C. coli has increased to 12.8% in 2010, up from 0.7% in 2007 when it first appeared in NARMS retail meat.

For E. coli:

• Ceftriaxone resistance among E. coli isolates from chicken breast is consistently higher than any other retail meat tested.
• From 2002–2005, nalidixic acid resistance in E. coli from chicken breast increased from 2.8–6.6% and increased in ground turkey from 4.3–10.4%. Since the fluoroquinolone ban in September 2005, resistance has decreased to 3.6% in chicken breast and 2.7% in ground turkey.
• Gentamicin resistance is much higher in retail poultry isolates (> 20%) than ground beef and pork chop isolates.
• A highly statistically significant trend in ampicillin resistance was seen among ground turkey with 52.6% resistance in 2010, up from 31.3% in 2002.

Here are some tables from the report, with the really troubling results for 2010 called out in yellow.

If you read down the left-hand column and then across to 2010, what these tables tell you is that more than half of the ground turkey samples carried E. coli that were resistant to at least three different classes of antibiotics, meaning that, if those bacteria caused a foodborne infection in a person, none of those antibiotic classes would work to cure it. Almost 30 percent of chicken breast and ground turkey samples carried Salmonella bacteria that were resistant to five different classes of antibiotics. Almost 29 percent of ground-beef samples carried Salmonella strains that were resistant to six.

**Not all the antibiotic-resistant trends in this report are negative. But overall? Honestly, they seem to just be getting worse.

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