New data from the Food and Drug Administration (FDA) show that sales of medically important antibiotics in food-producing animals fell by 2% last year.
The latest summary report from the FDA's Center for Veterinary Medicine (CVM) shows that 6.1 million kilograms (kg) of medically important antibiotics were sold and distributed for use in livestock (chicken, turkey, cattle, swine) in 2023, down from 6.2 million kg in 2022. Medically important antibiotics, which are tracked because they're also used in human medicine, accounted for 56% of all antibiotics sold for use in food-producing animals.
The FDA report notes that the volume of antibiotics sold and distributed for use in livestock and poultry in the United States has dropped by 37% from 2015, the peak year of animal antibiotic sales, and by 35% since 2014.
Cattle, swine account for most antibiotic sales
As in previous years, swine accounted for the highest percentage of medically important antibiotic sales (44%), followed by cattle (41%), turkey (10%), chicken (2%), and other food-animal species (3%). Sales of medically important antibiotics in 2023 declined for all species except swine and those in the "other" category.
Two-thirds (66%) of all medically important antibiotics sold for food-animal production were tetracyclines, which saw an increase in sales compared with 2022. Sales of fluoroquinolone antibiotics also rose. But sales figures for all other classes of antibiotics fell.
The report also includes an interactive chart on biomass-adjusted sales data, which adjusts raw annual antibiotic sales data to account for the total mass (the estimated population multiplied by the average weight) of each animal species potentially receiving those drugs. Animal biomass adjustment helps contextualize antibiotic sales data by accounting for the size and composition of animal populations, which can change from year to year.
That chart shows that biomass-adjusted sales, which provides an indication of the intensity of antibiotic use in food-producing animals, declined for several antibiotic classes in 2023. Fluoroquinolones, cephalosporins, and tetracyclines all saw increases in biomass-adjusted sales.
Although the decline in sales of antibiotics for use in livestock and poultry since 2014-15 is significant, much of the decline occurred in 2016 and 2017, when new FDA rules ending the use of medically important antibiotics for growth promotion and requiring veterinary oversight of antibiotic use on farms went into effect.
But after rising by 9% in 2018, US sales of antibiotics for food-producing animals have essentially plateaued over the last few years. And advocates for more judicious use of antibiotics in food-animal production say they're concerned about the trajectory.
"There was a little bit of a drop [in 2023], but we're still up quite a bit from where we were in 2017," Steven Roach, the Safe & Healthy Food Program Director at Food Animal Concerns Trust (FACT), told CIDRAP News. "And with certain species we're significantly higher than we were in 2017."
The biggest changes in antibiotic sales have been seen in the poultry industry. Since 2017, sales of antibiotics for use in chicken production have fallen by 45%. Chicken producers have led the way on more judicious use of antibiotics in recent years, as consumer demand for antibiotic-free chicken has driven the country's largest chicken producers to dramatically limit the use of antibiotics.
By comparison, sales of antibiotics for use in the cattle and swine have risen by 7.8% and 32.6%, respectively, since 2017.
"The poultry industry has continued to reduce their [antibiotic] use and has shown that it is possible," Roach said. "At the same time, antibiotic use in the pork and beef industry is going back up."
Better data needed
The concern about overuse of medically important antibiotics in food-producing animals is that it contributes to a reservoir of resistant bacteria that threatens animal and human health. The issue has been acknowledged by both US and international health organizations as a critical component of efforts to address rising rates of antimicrobial resistance (AMR).
At the recent United Nations High-Level Meeting on AMR, UN member states agreed a political declaration that, among other things, called for countries to "meaningfully reduce" the quantity of antimicrobials used in the agri-food system by 2030.
Having better data will be a crucial part of that effort. The FDA cautions that its annual report on sales figures doesn't provide a complete picture of how antibiotics are being used in US food-animal production or provide enough context to evaluate why a particular product is used. To address those shortcomings, the FDA said in a 5-year action plan released in 2023 that one of its goals is to facilitate the development and implementation of a sustainable system for collecting data on antibiotic use on US farms, and to publish more reports on those data.
"Collecting and analyzing data on antimicrobial drug use in animals remains a critical gap to understand the emergence of antimicrobial resistance and its potential relationship to use of antimicrobials in animals," the FDA wrote.
