Canada Reveals New List of Superbugs Threatening Public Health

Canada’s federal health officials have released an updated list of pathogens deemed the most significant threats to public health, identifying a total of 29 superbugs. This list, compiled by the Public Health Agency of Canada, highlights organisms that pose serious risks, including drug-resistant strains of bacteria and fungi that can cause severe illness or death.

Among the high-priority pathogens are Candida auris, a drug-resistant fungus with a mortality rate between 30 and 60 percent, and carbapenem-resistant Enterobacterales, which includes notorious bacteria like E. Coli and Salmonella. The update marks the first revision since 2015, reflecting the evolving landscape of antimicrobial resistance.

The selection process for these pathogens involved evaluating their treatability, transmission rates, and case fatality ratios. The assessment also considered the impact on vulnerable populations, including Indigenous communities, individuals who inject drugs, and newly arrived immigrants.

Dr. Gerry Wright, a professor of biochemistry and biomedical sciences at McMaster University, emphasized the urgent need for this updated list. “With no new drugs coming on the market, things are going to get to the point that we’re going to be seeing a lot more people staying in hospital or even dying, because the antibiotics are not working,” he stated.

A significant issue contributing to this crisis is antimicrobial resistance, which renders infections caused by bacteria, viruses, fungi, and parasites increasingly difficult to treat. According to the Public Health Agency of Canada, an estimated 14,000 deaths occurred due to antimicrobial resistance in 2018 alone.

Pathogens of Major Concern

The high-priority pathogens identified in the new list include:

– **Carbapenem-resistant Enterobacterales**: A family of bacteria that can lead to severe infections in the urinary tract, abdomen, and bloodstream.
– **Drug-resistant Gonorrhea**: An STI that has developed resistance to nearly all available antibiotics. In 2022, Canada recorded the highest gonorrhea rate in 30 years.
– **Carbapenem-resistant Pseudomonas**: Known for its intrinsic resistance to multiple antibiotics, this organism is particularly dangerous for individuals with cystic fibrosis.
– **Candida auris**: This fungus poses a significant threat in healthcare settings, where it can survive on surfaces for long periods and infect patients, especially those with weakened immune systems.

Dr. Kanchana Amaratunga, a medical advisor to Canada’s antimicrobial resistance task force, highlighted the repercussions of untreated gonorrhea, stating, “If you can’t treat gonorrhea, it can lead to pelvic inflammatory disease or infertility in the future.”

The list also includes Mycoplasma genitalium, a sexually transmitted infection that has emerged as a notable concern, alongside other well-known pathogens such as Streptococcus pneumoniae, which can lead to life-threatening conditions like meningitis and pneumonia, particularly in children and the elderly.

The Road Ahead

The updated watchlist is a response to the increasing prevalence of antimicrobial resistance, a global health threat that has prompted calls for more frequent evaluations. Dr. Wright noted the need for updates every three to five years, stressing that microbes can evolve rapidly. The urgency of this situation is exacerbated by the diminishing interest from pharmaceutical companies in developing new antibiotics, primarily due to economic factors.

Wright’s lab has made strides in identifying potential new treatments, isolating a protein from a soil bacterium that has shown efficacy against many of the pathogens on the list in laboratory settings. However, turning this discovery into a viable drug will require substantial investment and time.

Both Wright and Amaratunga stressed the importance of preventive measures, including responsible antibiotic use, improved surveillance, and early detection of infections. With nearly 68 percent of invasive pneumococcal disease cases in Canada being caused by vaccine-preventable strains, the significance of vaccinations cannot be overstated.

As Canada faces these evolving health threats, the updated list serves as a critical tool for public health planning and intervention, aiming to mitigate the impact of these formidable pathogens on the population.