Annual sales and distribution of antibiotics medicines for use in livestock increased between 2013 and 2014, according to the Food and Drug Administration, despite efforts in recent years to limit the overuse of drugs credited for the rise in antimicrobial resistant infections.
The FDA's released Thursday shows more than 16,000 tons of antibiotics approved for use in food-producing animals were sold and distributed in the U.S. in 2014, a 4% increase from 2013 and a 22% rise from 2009.
Sales of antibiotics deemed medically important for humans to use in livestock increased by 3% between 2013 and 2014, constituting a 23% hike from 2009.
Such medicines made up 62% of all domestic sales of antibiotics approved for use in livestock in 2014. Tetracyclines, a class of multipurpose antibiotics used for an array of conditions including urinary tract infections and chlamydia, accounted for 70% of sales to livestock, according the report.
Use of tetracyclines has declined in recent years as concerns grow over the rise in the number of organisms that have developed resistance to such medications, making them ineffective against such infections.
For years, health officials have warned against widespread use of antibiotic medications. The Centers for Disease Control and Prevention estimates 2 million antibiotic-resistant infections occur in the U.S. each year, resulting in more than 23,000 deaths and $20 billion in health-related costs.
While the CDC has focused its efforts on trying to reduce overprescribing of antibiotics among health professionals, advocates have fought to limit the use of such drugs in food-producing animals.
Some meat producers include antibiotics in the animal feed and drinking water of livestock to help them gain weight without having to increase the amount they eat. Public health advocates say those practices cause antimicrobial resistance, prompting the FDA in recent years to take measures to limit antibiotic use among livestock.
In 2013, the agency issued guidelines calling on companies that produce antibiotics for livestock to voluntarily remove any animal-growth references from their labeling for medicines deemed medically important to humans by December 2016. The largest drugmakers of such products, Eli Lilly & Co. subsidiaries Elanco and Zoetis, supported the rule at the time, stating they planned to limit labeling to reflect their antibiotics should be used for therapeutic purposes only.
In May, the FDA issued that would require the makers of antimicrobial drugs for use in livestock to collect and report sales data according to the species to better track the extent at which their products are used specifically in chickens, turkeys, cattle and pigs.
But some advocates argue that by focusing primarily on growth promotion, the FDA's guidance left loopholes that allow meat producers to use such drugs at the same level of frequency.
“They are still allowing many of the same uses to continue under the rubric of disease prevention, which is the same kinds of doses and still herd-wide used,” said Avinash Kar, an attorney with the Natural Resources Defense Council.
Kar called for the FDA and states to adopt the kinds of measures California enacted in October, when it became the first state in the country to go beyond federal rules that prohibit the use of antibiotics on livestock for non-medical purposes by further limiting their use for the purpose of staving off a potential disease.
Unless the FDA addresses both those problematic uses, growth promotion and disease prevention, overall usage isn't likely to decline in a significant way, Kar said.