In particular, the authors noted that antimicrobial resistance in bacteria found in livestock grown in low to medium-income countries has nearly tripled since 2000. This increase could be linked to the overconsumption of meat and meat products and could have serious consequences for human health.
According to the World Health Organization (WHO), antimicrobial resistance is a threat to preventing and treating an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi. This makes it a serious threat to global public health. In the report, researchers from Switzerland, Belgium, India and the U.S. gathered nearly 1,000 publications and unpublished veterinary reports to create a map of antimicrobial resistance (AMR) in low- to middle-income countries. The team focused on Escherichia coli, Campylobacter, Salmonella and Staphylococcus aureus, all known to cause serious infections in both animals and humans.
According to the researchers, what they found was that between 2000 and 2018, the proportion of antibiotics showing rates of resistance above 50 percent in developing countries increased in chickens from 0.15 to 0.41 and in pigs from 0.13 to 0.34. This, the researchers said, meant that antibiotics that could be used for effective treatment failed more than half the time in 40 percent of chickens and one-third of pigs raised for human consumption.
The highest resistance rates, the team said, were associated with the antimicrobial medication most frequently used in animals such as tetracyclines, sulphonamides, penicillins and quinolones.
Antibiotic resistance in livestock, the research team explained, was most widespread in northeast China and northeast India, with southern Brazil and Kenya emerging as new hotspots.
These troubling findings, the study’s first author Thomas van Boeckel said, reflect the growth in the meat industry in the mentioned countries, noting that while they continue to experience explosive growth in terms of meat production and consumption, their access to veterinary antimicrobials remains largely unregulated -- a fact that could lead to more serious problems in the future. (Related: The easiest way to stop antibiotic resistance is to start eating (and growing) organic.)
“We certainly do want higher-protein diets for many people, but if this comes at the cost of failing antibiotics, then we need to evaluate our priorities,” study co-author Ramanan Laxminarayan said in a statement.
According to the research team, the nations affected by AMR should restrict the use of human antibiotics in farm animals. At the same time, the research team said, more affluent nations must support a transition to sustainable farming in those countries, possibly through a global fund to subsidize biosafety and biosecurity improvements.
“The rich countries of the Global North, where antimicrobials have been used since the 1950s, should help make the transition a success,” Van Boeckel said, adding that failure to do so could result in the global spread of infectious -- and resistant -- bacteria.