Antibiotic Resistant Bacteria: Another Global Health Crisis


                   By Dr Michael W. Fox 

Antibiotics were once a life-saver but their misuse is rendering them increasingly ineffectual against a variety of common infections in us and our animal companions. The Star Tribune Editorial, “Renew the battle vs. antibiotic resistance” (Dec 2nd 2022) supports the legislation dubbed the ‘Pioneering Antimicrobial Subscriptions to End Upsurging Resistance” (PASTEUR) Act now before Congress would provide drug companies with $6 billion to develop new antibiotics. This warrants some reflection considering the fact that the pharmaceutical industry has been long aware of this problem yet continued to promote and sell antibiotics to the livestock and poultry sectors at home and even abroad after domestic use of some antibiotics was eventually prohibited.

Back in the early 1980s I was involved in addressing various animal welfare, environmental and public health concerns involving intensive animal “factory farms” which were documented in my 1986 book Agricide: The Hidden Farm and Food Crisis That Affects Us All. I met with the Director of the Bureau of Veterinary Medicine to appeal for immediate action to curtail the feeding of human-life-saving antibiotics to farm animals which were being given to boost productivity and profits and to protect them from diseases to which the inhumane conditions of over-crowding in CAFOs ( concentrated animal feeding operations) made them more susceptible. He shook his head, pointing to a pile of reports on his desk supporting my concerns about increasing bacterial resistance to antibiotics and told me that because of the political power of the pharmaceutical industry and livestock and poultry sectors, his hands were tied.

Now, over 40 years later we face the consequences of what I consider tantamount to a crime against humanity stemming from this profit-driven misuse of antibiotics, compounded by the over-prescribing of physicians and over-the -counter availability in many countries. Evidence of the obesogenic effects of antibiotics and their disruption of healthy gut microbiomes leading to a number of health problems are now surfacing along with evidence that some non-antibiotic pharmaceuticals can enhance bacterial antibiotic resistance. ( Vallianou N, et al. Do Antibiotics Cause Obesity Through Long-term Alterations in the Gut Microbiome? A Review of Current Evidence. Curr Obes Rep. 3:244-262.2021. Min Jin, et al. Antidepressant fluoxetine induces multiple antibiotics resistance in Escherichia coli via ROS-mediated mutagenesis Environment International,120: 421-430, 2018.).

An analysis of human deaths associated with antibiotic resistant bacteria published in The Lancet on 19 January 2022, estimates that in 2019, 4.95 million people died from illnesses in which bacterial antimicrobial resistance (AMR) played a part. Of those, 1.27 million deaths were the direct result of AMR — meaning that drug-resistant infections killed more people than HIV/AIDS (864,000 deaths) or malaria (643,000 deaths); and is the second biggest killer globally after coronary heart disease. (Murray, C. L. J. et al. Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis. Lancet (2022).

Some antidepressants, now widely prescribed, have been shown to increase bacterial resistance to antibiotics. ( Ding P, Lu J, Wang Y, Schembri MA, Guo J. Antidepressants promote the spread of antibiotic resistance via horizontally conjugative gene transfer. Environ Microbiol. 2022 Nov;24(11):5261-5276. doi: 10.11111462-2920.16165).

According to a recent comparative analysis by David Wallenga with the Natural Resources Defense Council of human and farm animal use of antibiotics, “Use of antibiotics in human medicine has remained consistent since 2009. It even declined slightly since 2017, despite the year-on-year increase in the U.S. population. By contrast, sales of these same drugs for use in livestock increased 11.3% from 2017 to 2019, from 5.6million kg to 6.2million kg. Livestock sales are now nearly double the sales for human medicine (6.19million kg vs. 3.30Mmillionkg). The net increase in livestock sales since 2017 is entirely due to more antibiotics being sold for use in pig and cattle.” (

His analysis concludes with this important statement: “”The CDC states that 75% of dangerous new infections, including pandemics, spill over from animals to human populations. These animal-borne threats include viruses as well as new forms of antibiotic resistance genes and the multi-drug resistant superbugs that carry them. Pandemic preparedness and public health protection should be our nation’s foremost priority. We must therefore invest to robustly to track antibiotic resistance and antibiotic use wherever it occurs.”

The amount of antibiotics used in animal farming is underestimated in official reports. Researchers collated figures from sources such as farm surveys and drug sales, because “the majority of data on antibiotic use in the world is unusable”, according to epidemiologist Thomas Van Boeckel. Calculations of antibiotic usage in 229 countries suggest that Africa’s use is probably twice what the World Organization for Animal Health reports, and use in Asia is 50% higher than reported. Globally, antibiotics use in farmed animals is projected to grow 8% between 2020 and 2030. An estimated 107,500 tons of antibiotics will used in 2023 for farmed animals compared to 100,000 tons in 2020.

China, Brazil, India, Australia and USA are the top consumers of antibiotics for use in cattle, sheep, poultry and pigs. There are efforts to curtail agricultural antibiotics use, which could drive drug-resistant infections in humans. Reference: PLoS Global Public Health paper Mulchandani R, Wang Y, Gilbert M, Van Boeckel TP (2023) Global trends in antimicrobial use in food-producing animals: 2020 to 2030. PLOS Glob Public Health 3(2): e0001305.

Extensive use of antibiotics on livestock may restrict soil carbon by altering soil microbial ‘carbon use efficiency’ or the efficiency with which microorganisms convert absorbed carbon into their own biomass.( Shamik Roy, Dilip G. T. Naidu, Sumanta Bagchi, Functional substitutability of native herbivores by livestock for soil carbon stock is mediated by microbial decomposers. Global Change Biology, Volume29, Issue8 April 2023 Pages 2141-2155.

“Antibiotics enter the soil through livestock and there they affect the microbial communities,” states co-author Sumanta Bagchi. “The altered microbial community is less efficient in storing carbon. Overall, livestock-soil stores 30% less carbon than wildlife-soil (soil impacted by dietary habits of wild herbivores). Some of this difference could be due to antibiotics, but we don’t know how much of this arises from antibiotics.” The findings highlight the importance of continued conservation of native herbivores and new ideas to improve livestock management, the study concludes. They suggest that sequestering antibiotics, along with the restoration and rewilding of soil microbial communities may offer nature-based climate solutions by improving soil carbon storage in areas under livestock.

Applying the precautionary principle along with good sanitation, safe food handling and personal hygiene will reduce the harmful costs and retrieve the benefits of antibiotic use along with probiotics for medical and veterinary purposes. Curtailment of antibiotic use in farmed animals to boost productivity must become a global priority since prohibitions in one country will not provide adequate protection when other countries continue regardless.