Thank you so much for inviting me.
I'm an assistant professor in agricultural microbiology at McGill University. My area of research expertise is the use of antibiotics in farming, antibiotic resistance and the development of replacement products for animal health and growth promotion.
Unfortunately, we're on the cusp of an antibiotic resistance crisis having major negative influences on agricultural productivity and therefore food costs and food security.
Antibiotics are small molecules that are used to slow or stop the growth of bacteria. They're commonly used in medicine to treat bacterial infections. In addition to infections, they're used in routine medical procedures such as surgeries, chemotherapy and childbirth due to their prophylactic or disease-prevention activities.
We've been using antibiotics in farming since the 1930s. They're used to treat bacterial infections in farm animals, but they can also be used to prevent infection or promote growth. The line between preventing infection and promoting growth is pretty blurry, since animals tend to grow better when they're not fighting bacterial infections. The problem is that, the more antibiotics we use, the faster bacteria become resistant to them.
The world is in a lot of trouble in terms of antibiotic resistance. A recent peer-reviewed report published in The Lancet found that in 2019 there were about 4.95 million human deaths associated with bacterial AMR infections. This is not an acute issue. We are seeing consistent year-over-year increases in human deaths associated with antibacterial-resistant infections, and our current projections are that by 2050 we will see 10 million human deaths per year due to AMR infections.
To be extremely clear, there's no simple fix for this. AMR deaths are caused by a range of different bacteria, and we cannot create a single vaccine or even groups of vaccines that will solve this problem, so I'll repeat that the more antibiotics we use, the faster we accelerate towards annual human death counts due to AMR.
It's difficult to come up with a number on exactly how many antibiotics we use on Canadian farms, but we estimate that about 82% of antibiotics in Canada are used on farms and not in hospitals. The knee-jerk response is a ban on antibiotics in agriculture, but this is a really bad idea. Agricultural practices evolved alongside the availability of antibiotics, and it will take time to completely remove them without catastrophic effects to productivity.
I'll give you a few examples. Prior to antibiotics becoming widely available, dairy farmers had 95% more incidences of mastitis than they do today. Mastitis is a bacterial infection that is painful for the cow, reduces milk productivity, reduces cow lifespans, and even with antibiotics, costs Canadian dairy farmers about $700 million annually. If an outright ban was placed on antibiotics today, economists estimate that it would lead to an additional cost of $46 to $73 per cow due to increased numbers of infections, and this would seriously impact the stability of the dairy industry.
I'll give you another example. We use antibiotics in the feed of a lot meat chickens, also called broilers. Broilers are typically raised to market weight in 40 days. The mortality of no-antibiotics-ever chickens is about 4.2%, compared with 2.9% for conventionally raised chickens. This is a difference of 1.3%. It might sound very small, but our neighbours to the south produced 10 billion chickens last year, making 1.3% equal to 130 million chickens. The fact that these birds died of disease and cannot enter the food chain is sad by itself, but it also represents acres of grains and the carbon emissions used to harvest those grains that have now gone to waste, and the water used to feed the birds that's now gone to waste, and the animals themselves. In addition, no-antibiotics-ever birds have higher rates of diarrhea, which leads to higher incidences of eye burns, footpad lesions and airsacculitis, each of which is an indicator of uncomfortable birds and poor bird welfare.
To summarize, my concern is that, when deaths due to AMR in humans begin mounting, there will be public outcries against agricultural uses of antibiotics. This could result in a swift ban of antibiotic use in the agricultural sector, and if it happens too quickly and without proper replacement products, there will be increased prices in food markets, and we'll see supply shortages, which will compound the medical problems that we'll be dealing with at the same time. It's better to act now to address this because we do see it coming.
Thank you.