Growing concern over drugs fed to animals

by Jean-Louis Santini

Drugs fed to animals to promote growth and prevent diseases may play a key role in the emergence of antibiotic resistant bacteria, microbiologists said Sunday.

The practice of administering large quantities of "favors the emergence of that can spread to humans through the consumption of , from direct contact with animals or by environmental spread," said Awa Aidara-Kane of the .

"In addition, genes encoding for resistance can be transmitted from zoonotic bacteria to ," added Aidara-Kane, who leads the WHO Advisory Group on Integrated Surveillance of Antimicrobial Resistance.

She was speaking during the 51st annual Interscience Conference on meeting this weekend in Chicago.

In order to reduce the risk of the emergence and spread of resistant bacteria via the consumption of animal food products, the WHO suggests restricting and even eliminating the use of antibiotics to boost animal growth.

The world health body recommends limiting administering to animals the types of antibiotics considered essential to human health, such as fluoroquinolones and the most recent generations of cephalosporins.

"We are seeing a significant increase in resistance to third and fourth generation cephalosporins in Salmonella Heidelberg infections in humans," noted Beth Karp, a senior veterinary with the US Centers for Disease Control and Prevention.

"Between 2008 and 2010 resistance increased from 8 percent to 24 percent. In retail chickens isolates, resistance in Salmonella Heidelberg increase from 17 percent in 2008 to 31 percent in 2009."

The strain is resistant to nearly all antibiotics.

Karp also expressed concern about the risk of resistance to cephalosporin antibiotics in other Salmonella serotypes.

Nontyphoidal Salmonella is the main cause of food poisoning in the United States and affects about 1.2 million people each year, including 23,000 who are hospitalized and 450 who are killed, according to the CDC.

In late May, consumer groups lodged complaints with the Food and Drug Administration denouncing the widespread use of antibiotics in animal feed and urging the agency to do more to halt the practice.

The FDA had encouraged breeders last year to administer less antibiotics in order to reduce the risk of anti microbial resistance.

J. Glenn Songer, a research professor at Iowa State University's College of Veterinary Medicine, noted certain strains of the Clostridium Difficile bacteria that cause diseases in farm animals such as young pigs play a growing role in human infection.

C. Difficile resists most treatments and is a serious threat in hospital environments.

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dogbert
5 / 5 (1) Sep 19, 2011
We are constantly reminded of the obvious effects of general antibiotic usage in farm animals for growth resulting in multiply resistant organisms.

We observe a continual reluctance of governments to stop this practice.

Why can we not expect the FDA and the Agriculture Department to say "NO!"? Why can we not expect farmers to say "NO!".? The feed and seed producers (Monsanto, et al) exert such an unshakable influence on the government that such known problems, even when they result in human deaths, are brushed aside.
deluxestogie
not rated yet Sep 19, 2011
I believe we were discussing this very issue in the early 1970s. No news here.
JRDarby
not rated yet Sep 19, 2011
It is a question of (a) short-term gains for the producers and enablers (corporations like Monsanto) at the cost of financial and other externalities borne by consumers, farmers, and society as a whole vs. (b) long-term sustainability for the whole at the cost of profitability for some of the producers.

Unfortunately, there is simply no reason, in practical terms, for corporations to care about the externalities. The board members are grey-haired and will likely not see the result of these practices (and meanwhile they can sip organic, GM-free piña coladas while eating free-range steaks in their penthouse suites). Regarding corporate practices and their effects, the average consumer generally (a) doesn't know and (b) sadly doesn't care. I know scores of people who know how factory farming works and the vast majority of them would rather eat their antibiotic/pus/excrement/hormone/etc-filled burger and not think about the consequences than pass on it and be healthier.
JRDarby
not rated yet Sep 19, 2011
The fact of the matter is that unless there are sound economic (read: monetary) reasons for the corporations themselves, and the stock prices that represent them on Wall Street, and the controllers of these legal fictions (i.e. the board members) to change their behavior, nothing will change.

Worst case scenario: resource depletion occurs, prompting a sudden and perhaps catastrophic shift in the structure of the industry that is unlikely to be a step in the right direction.
Best case scenario: regulations may be put in place to bring reality back into agriculture and other industries--namely to impose costs onto the producer that existed all along but were merely externalized to the consumer and society as a whole.