The information is part of a summary released at the end of December by the US Food and Drug Administration (FDA) covering sales and distribution of antimicrobials. The annual report includes data up through 2015.
The total amount sold domestically was about 15,576,975 kg or 17,179 tons, the agency said. Medically important antimicrobials accounted for about 9,701,978 kg or 10,694 tons.
Sales and distribution of products for use in feed, also considered medically important for people, increased, according to the FDA report. “Certain other antimicrobial drugs are not considered medically important. Ionophores, for example, lack utility in human medicine and their use in animals, primarily as coccidiostats, does not pose cross resistance concerns; thus, they do not have the same public health risks as medically important antimicrobials,” it added.
Drug sponsors that sell antimicrobial drugs are required to report on the amount either sold or distributed annually, said the agency. However, there may be a difference between the amount sold and what is actually used.
Changes in reporting requirements and regulation regarding the use of antimicrobial drugs in animal feed or production are in progress, said the FDA. A breakdown of product sales for specific species is set to be recorded in next year’s data and results from ending the use of some products for growth promotion is not expected to be reflected in results until the following year.
"While we are hopeful that the changes made under GFI [guidance for industry] #213 will help slow the development of antimicrobial resistance, it’s too soon to speculate or quantify that impact," an FDA spokesperson told FeedNavigator. "We’re working in collaboration with other agencies including USDA and CDC to develop approaches for enhancing ongoing data collection efforts in order to assess the impact of these changes over time."
“The FDA is working with federal, academic and industry partners to obtain more information about how, when, and why animal producers and veterinarians use those classes of antimicrobial drugs that are important to human medicine,” the agency said.
Influence of VFD
New regulations regarding the use of antimicrobial products that are considered medically important for humans started this month. The drugs will no longer be available without veterinary approval or for use in growth promotion.
Veterinary Feed Directive (VFD) drugs will need a written statement from a veterinarian before it can be sold, the agency said.
Antimicrobial use
From 2014 to 2015 there was an 1% growth in domestic sales and distribution of all antibiotics approved for use with production animals, and there was a 24% growth from 2009 to 2015, said the FDA.
Sales and distribution of antimicrobials considered medically important for humans, but also approved for use in feed or animal production, grew by 26% from 2009 to 2015, and by 2% from 2014 to 2015, the agency said. “In 2015, domestic sales and distribution of medically important antimicrobials approved for use in food-producing animals administered in feed accounted for 74% of the domestic sales of all medically important antimicrobials for use in food-producing animals, while products administered by water accounted for 21%,” it added.
“In 2015, domestic sales and distribution of medically important antimicrobials accounted for 62% of the domestic sales of all antimicrobials approved for use in food-producing animals,” said the FDA. “Tetracyclines accounted for 71% of these sales, penicillins for 10%, macrolides for 6%, sulfas for 4%, aminoglycosides for 4%, lincosamides for 2%, and amphenicols, cephalosporins, and fluoroquinolones each for less than 1%.”
Of the medically important products, 29% were approved for use only in therapeutic purposes, while 71% could be used for production or therapeutic reasons, the agency said.
Tetracycline accounted for the largest sales volume of the medically important antimicrobials, the agency reported. Sales grew 4% from 2014 and totaled about 6,880,465 kg or 7,584 tons in 2015.
Sales and distribution of tetracyclines for use in feed grew by 31% from 2009 to 2015, the agency said.
The medically important antimicrobial that saw the most growth from 2014 to 2015 was aminoglycoside, the agency said. The sales volume increased by 13%.
Some antimicrobial products are approved for both production animals and companion animals, like dogs or cats, the agency said. In those situations, at this time, it is unclear what proportion of a product was used for which species.