Tests at meat packing plants show no reduction in drugs, a year after new rules to clamp down on overuse

Antibiotics crucial to human medicine are still being used in “unacceptable” quantities on US livestock farms, despite rules brought in last year to curb their use and combat the spread of deadly superbugs.

Tests on thousands of meat samples by the US Food Safety and Inspection Service (FSIS) show that powerful antibiotics classified as “critically important” to human health are still being used. The widespread use of such drugs on livestock is one of the key drivers of antibiotic resistance, a growing public health crisis.

Regulations brought in by the Food and Drug Administration (FDA) in January 2017 banned the use of antibiotics on livestock without a prescription from a vet and made it illegal to use the drugs solely to make animals fatter, which for years had been common practice on industrial farms.

The new rules aimed to ensure antibiotics were only used when medically necessary. But tests on livestock slaughtered at dozens of US meat packing plants – including some operated by major processors such as Tyson, Cargill and JBS – found “critical” antibiotics were still in use in many meat supply chains. There had been no reduction in the number of antibiotics found in samples from the year before the regulations came into effect.

Analysis by the Bureau of Investigative Journalism also shows how a loophole allows US farmers to continue to use many antibiotics targeted by the ban in much the same way as they could before the ban, including drugs previously used for growth promotion.

The findings indicate that more needs to be done to combat overuse of antibiotics on farms, critics say.

But meat industry representatives said it was impossible to draw meaningful conclusions from the data. The samples only indicated the presence of antibiotics, they pointed out, with no information about what diseases were involved or how the drugs were administered. All the drugs in question were approved for use on animals by the FDA.

‘Last defence’ against deadly infections

Unpublished FSIS records spanning a four-year period between 2013 and 2017 detail the results of the official chemical residue testing programme at US meat plants, in which 180,000 samples per year were analysed for substances that could potentially have an impact on human health.

The data, obtained by the Bureau and the Guardian, showed that 13 separate antibiotics classed by the World Health Organization (WHO) as “critically important” to human medicine were still being used in meat supply chains.

Of these, nine are classified as being “highest priority critically important”. The WHO recently warned that this class of antibiotics is so essential to human medicine that they should no longer be used in livestock farming. The antibiotics involved are often “the last line, or one of limited treatments, available to treat serious bacterial infections in humans”, it said.

Overuse of antibiotics enables bacteria to develop resistance, meaning drugs will no longer work. Antibiotic resistance is one of the gravest public health threats facing the world, and is said to be responsible for the deaths of 23,000 Americans each year, and a further 700,000 people around the world. (For comparison, about 40,000 people were killed in car accidents in the US in 2017.)

The FSIS data also showed that there had been no reduction in the number of antibiotics that turned up during testing. In 2016, the year before the restrictions came into force, the number of residues of “highest priority critically important” antibiotics was 363. The number actually increased after the new restrictions came into force, to 461 in 2017.

More than 150 meat plants were found to have at least one “critically important” antibiotic in use within their supply chains. A total of 46 plants had five or more, and 18 had nine or more.

Some of the plants at which samples were tested are operated by major US processors. Medical experts and pressure groups said the findings showed much more needed to be done, and that meat companies should pressure farms to reduce antibiotic use.

“It is absolutely crucial that these practices end,” said Dr Thomas Van Boeckel, a scientist from the Swiss university ETH Zurich, who has mapped the use of antibiotics in animals globally.