Antibiotic resistance detected in food chain a cause for concern

A new study has found surprisingly high rates of antibiotic resistance in samples of salmon and beef purchased from Australian supermarkets.

The study, shared exclusively with 7.30, was commissioned by animal rights not-for-profit World Animal Protection and carried out by researchers at Melbourne’s Monash University.

The researchers looked at how well antibiotics worked against bacteria in salmon and beef and also searched for what antibiotic-resistant genes the micro-organisms might be harbouring.

These genes can jump between bacteria, and from bacteria to humans through consumption.

“Alternatively, you would also have these genes potentially passing into wastewater, for instance, and then also causing environmental contamination,” said Associate Professor Chris Greening from Monash University.

Fifty-five per cent of the beef samples and 39 per cent of the salmon samples were found to be harbouring resistance to a range of commonly used antibiotics.

Big pieces of Norwegian salmon are stacked on top of each other in a fridge at a supermarket.
Thirty-nine per cent of salmon samples tested were found to harbour resistance to a range of commonly used antibiotics. (Flickr: BakiOguz)

“It’s a concern. The levels of antimicrobial resistance in these meats was much, much more than we were expecting,” Mr Greening said.

“We can’t really conclude exactly how the antimicrobial resistance in these meats was acquired.

“What’s clear is, because of the very high levels of antimicrobial resistance, they’re probably exposed to antibiotics at some point, but we can’t determine in what context and for what purpose.”

It’s possible that cooking the meat reduces the risk of transmission.

But Mr Greening said not enough was being done to monitor antibiotic resistance in the food chain.

Cattle walking in long, green crops under a right blue sky.
Chris Greening says an integrated surveillance system is needed in Australia to monitor antimicrobial usage. (Supplied: Elders Wagga Wagga)

“What Australia desperately needs is basically an integrated surveillance system for both antimicrobial usage as well as antimicrobial resistance levels,” he said.

“We also need to be looking at animal health, we need to be looking at food, we need to be looking at [the] environment.”

Food Standards Australia New Zealand said it would be monitoring antibiotic resistance from June 2022 as part of a new study looking at antibiotic resistance in Australian food. It said it was analysing the research from Monash University.

Coles, Woolworths, and Aldi all declined to be interviewed.

In a statement, a spokesperson for Woolworths said the company takes food safety seriously and relies on “the expert guidance of national authorities who set science-based regulations for the livestock industry and animal medicine”.

The Department of Agriculture, Water and the Environment also told 7.30 in a statement that the study’s findings “are not reflective of current antimicrobial usage practices” in Australia’s beef or salmon industry. 

Antibiotic resistance ‘a real problem’

Antibiotic resistance is becoming a global problem that could make infections much harder to treat.

“Antibiotic resistance is where antibiotics no longer work because bacteria produce chemicals that inactivate the antibiotic, and that’s a real problem,” said Peter Collignon, an infectious diseases physician and microbiologist at the Canberra Hospital.

Blister packs of antibiotic tablets
Antibiotic resistance is becoming a global problem. (Flickr.com: Global Panorama (CC-BY-SA-2.0))

“There’s people already dying around the world because they’re getting infections that we can no longer treat.

“And as the projections go for the future, they’re talking about millions of extra people dying per year because antibiotics don’t work.

“It just shows why we have to be very careful with the volumes of antibiotics we allow to be used, the types that are used, and how we let it spread.

“If we don’t have transparency of what’s happening with real-time or near real-time data, then it’s very hard to police this.”

The Australian Pesticides and Veterinary Medicines Authority (APVMA) said it is responsible for approving antibiotics, but that it is up to state and territory regulators to monitor how much is used.

A spokesperson for the Department of Agriculture also told 7.30 that the department is in the initial planning stage for “a nationally coordinated One Health Surveillance System that will collect and report on antimicrobial resistance and antimicrobial use” across sectors including agriculture, food and animal health. 

Beef industry taking concerns ‘very seriously’ 

Bryce Camm runs his family’s cattle company in Queensland’s Darling Downs.

He’s well aware that antibiotic resistance is a serious issue, and says he tries to limit his use of antibiotics.

The only part of Mr Camm’s business where antibiotics are used is to treat disease among cattle in the feedlot.

“We’ll use antibiotics when we have a beast with an ailment, that might have had a cut or an abrasion,” Mr Camm said. 

“Or it might have a respiratory [illness] or something like what we would call the flu in humans.

“Before we can use an antibiotic on any animal, it has to be authorised or signed off by a veterinarian.

“So Australia has some of the lowest usage of antibiotics in the world.”

Farmer wearing a blue shirt and cap, standing behind a fence.
Bryce Camm says he tries to limit antibiotic use on his cattle. (ABC News: Alex McDonald)

Mr Camm says he is working hard to avoid making the problem of antibiotic resistance worse.

“Antimicrobial resistance in the management of antibiotics, both in human health and animal health, is an emerging issue globally,” he said. 

“[It is] something that the beef industry … takes very seriously. 

“We understand how crucial it is to maintain the efficacy of those important medicines that we have today.

“We’re always very conscious of emerging issues for consumers and ensuring that we’re delivering a safe and nutritious product onto the plate. 

“And hence, we have been world-leading in implementing stewardship guidelines around the use of antibiotics.” 

Cows eat next to a fence.
Bryce Camm says more work is being done to understand the impact of antibiotic use in feedlot operations like his. (ABC News)

A Department of Agriculture spokesperson told 7.30 that Australia had adopted “one of the most conservative approaches to the use of antimicrobials in agriculture in the world”, and that the registration process for antibiotics for use on food-producing animals takes a “science and risk-based approach”. 

“Australia has a national antimicrobial resistance strategy that reflects the shared responsibility of human health, agriculture and environment and the best available scientific knowledge of this topic,” the statement said.

© 2020 Australian Broadcasting Corporation. All rights reserved.
ABC Content Disclaimer

Written by ABC News

LOADING MORE ARTICLE...