Antibiotics are one of the great modern medical innovations.
But they’re not infallible: microbes are constantly evolving to better resist their effects. And as they do, some of the treatments we take for granted — things like caesarian sections, chemotherapy and organ transplants — are at risk in a future where it’s harder to fight off an infection, a new report suggests.
“Antibiotics have been an amazing miracle drug in many ways,” said Amélie Quesnel-Vallée, a professor and Canada Research Chair in policies and health inequalities at McGill University.
“In that sense, it’s not surprising in this regard that they were used very, very broadly, maybe overused in some ways. And now we’re seeing the impact of that.”
This means increasing antibiotic resistance in patients, hospitals and the community. A new report commissioned by the federal government, called “When Antibiotics Fail,” estimated that by 2050, around 40 per cent of infections could be resistant to first-line antibiotics.
This is a problem, the report said, given the “ubiquity” of antibiotics in modern medicine.
“Antimicrobials are used for the treatment, but also prevention, of infections,” the report reads. “For example, many surgeries and other medical procedures, including chemotherapy, are dependent on prophylactic treatment with antimicrobials. Ineffective antimicrobials will ultimately change the way that most people access and plan the care of their health.”
The report, which estimated that around 400,000 Canadians are likely to die from drug-resistant infections by 2050, noted that the effects of antimicrobial resistance wouldn’t just be limited to infected individuals.
“Rather, our entire health-care system, which is now heavily reliant on antimicrobials, would be disrupted,” it said.
Most surgeries, except for very simple procedures, require prophylactic antibiotics — antibiotics given beforehand to try to prevent an infection — said Dr. John Conly, an infectious disease physician with Alberta Health Services and a professor at the University of Calgary who was part of the panel that prepared the report.
“It’s a mainstay part of the care when you come in to have any prosthetic materials, hips, knees, pacemakers, heart valves or shunts that are placed — any foreign material that’s put into the body,” he said.
Right now, around two to five per cent of surgeries result in a post-operative infection, higher if they’re a particularly dirty procedure like repairing a perforated bowel, or some trauma surgeries, he said.
“Certainly, that might increase if we were to see the resistance levels rise to what the trajectory is looking at.”
Transplant patients are at especially high risk of developing infections, especially because the medication they’re put on to reduce the chances of their body rejecting the new organ suppresses their immune system, said Dr. Shahid Husain, a professor of medicine at the University of Toronto and director of transplant infectious disease at Toronto’s University Health Network.
For this reason, doctors end up “marinating” these patients in antibiotics at the first sign of any infection, he said, which actually increases their chances of developing drug-resistant infections down the road. And many potential transplant recipients, as a result of their illness, already have compromised immune systems even before they get surgery.
So what happens if our antibiotics don’t work as well? It could change how doctors treat their patients, he said.
“Having an infection, and on top of that, a multi-drug-resistant infection, that delays the receipt of a life-saving procedure.”
If someone has an untreated infection, they’re not going to be getting a transplant, he said, even if it would be a life-saving procedure for them, as the risks are too high.
“The bottom line is, if you have untreated infections, whether it is MDR (multi-drug resistant) or non-MDR, no one is going to give you a transplant.”
The risk-benefit analysis for elective procedures could change, too, in a world with more drug-resistant organisms, Quesnel-Vallée said.
“What is really striking to me is that the elective procedures such as arthroplasty surgeries — so knee and hip replacement surgeries — would not be as routine as they are now in a context where we have a potential for higher drug-resistant infections.
“So people would probably be thinking twice about getting those, and that would have severe consequences, of course, for their mobility and their active life expectancy.”
The health system needs to combat this risk by cutting back on inappropriate prescribing, the use of antibiotics in agriculture and continuing to investigate new treatments like phage therapy to combat infection, Husain said.
“The antibiotic is a very precious resource, which, unfortunately, is spent or distributed like candies.”