Slowing down the superbugs
World Antibiotic Awareness Week was held from November 12-18, 2018 to focus attention on the prevalence of infections that are difficult to treat because they are caused by pathogens that are resistant to currently available antimicrobial drugs. Antimicrobial resistance (AMR) is a concern because it can drastically reduce options for treating many common illnesses. According to the World Health Organisation (WHO), AMR results from the overuse of antimicrobials among humans and animals. Antibiotics, the most commonly used group of antimicrobial drugs, are designed to kill or weaken bacteria but certain resistant strains are unaffected by these drugs. These strains survive treatment, multiply and continue to cause illnesses. This process is natural but speeds up with increased use of antibiotics. The problem was recognised as early as 1945 by Alexander Fleming, just 17 years after he discovered penicillin and AMR has accelerated since then. AMR cannot be stopped, but can be slowed through integrated strategies that include activities such as inspections, surveillance and outreach by EPH practitioners.
The Public Health Agency of Canada’s (PHAC), Federal Action Plan on Antimicrobial Resistance and Use in Canada is a coordinated, inter-agency approach engaging stakeholders from all regions and levels of government. This plan aims to slow AMR and reduce the spread of AMR-related infections by:
- preserving the effectiveness of existing treatments;
- reducing infection rates through health promotion and prevention;
- improving surveillance; and
- promoting innovation to develop new control and treatment options.
Several programs within PHAC’s plan are strongly linked to food safety. According to Canada’s Integrated Program for Antimicrobial Resistance Surveillance (CIPARS), in 2015, 82% of antimicrobial drugs used in Canada were given to livestock. Overuse in routine practices such as administering antibiotics in feed, prophylactically or to promote growth, have made the livestock industry a major contributor to AMR. Figure 1 (below) illustrates how resistant bacterial strains can spread to humans through contaminated meat, fish, eggs and dairy products as well as through soil, water, irrigated crops or by direct contact with infected animals.
CIPARS monitors AMR in Escherichia coli (E. coli), Campylobacter and Salmonella in farms, slaughterhouses and retail establishments. These three bacteria cause foodborne illnesses and resistance is widespread. For example, in 2014, E.coli strains were found to be resistant to seven antibiotics used to treat infections in animals and people. Resistance was especially high to Tetracycline: 69% of E.coli isolates from pigs, 50% of the isolates from chickens and 20% of the isolates from cattle were resistant to this antibiotic. The Health Canada Veterinary Drugs Directorate (VDD) is promoting judicious use of medically important antimicrobials in partnership with the Canadian Animal Health Institute (CAHI) and CIPARS.
EPH’s role in infection prevention, a priority within the PHAC plan, has added significance within the context of AMR. Minimising the transmission of food and water borne pathogens helps prevent infections and lowers the need for treatment. This may contribute to slowing the AMR process and prolonging the effectiveness of available antibiotics.