Superbugs A Growing Threat in Canadian Hospitals

Armen Hareyan's picture

Canadian Hospitals and Superbugs

A new study of antibiotic-resistant bacteria in Canadian hospitals shows that powerful bacteria such as methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE), are more prevalent than previously believed. The Canadian National Intensive Care Unit (CAN-ICU) study is led by the combined efforts of the University of Manitoba, the Winnipeg Health Sciences Centre, and the National Microbiology Laboratory, in Winnipeg.

Diligence in infection control is essential, say the study's authors, along with new treatment options, such as new broad-spectrum hospital antibiotics. According to the Community and Hospital Infection Control Association, 8,500 Canadians die each year due to complications arising from infections acquired in hospital.

"The stark reality in this country today is that MRSA and other drug-resistant bacteria are posing a serious threat to our ICUs," says primary investigator, Dr. George Zhanel, Professor, Department of Medical Microbiology, Faculty of Medicine, at the University of Manitoba. "People infected with these superbugs are more likely to have longer hospital stays and require multiple drug treatments to fight them off and even then, it's often too little, too late."

Data from the CAN-ICU study has revealed that among S. aureus bacteria, which is a major cause of hospital-acquired wound and skin infections, on average one in five (20%) and as high as one-half (50 per cent) were resistant to the antibiotic methicillin. This is higher than previous estimates, which suggested MRSA had a prevalence of between 5 and 15 per cent. Researchers also found a 6.8 per cent prevalence of VRE and a 4.7 per cent prevalence of antibiotic-resistant E. coli.

According to Dr. Zhanel, a multi-pronged approach to infection control is required to help reduce antibiotic resistance in Canada. Stringent measures must be adhered to, such as appropriate prescribing practices and strict compliance among patients for less complicated infections, diligent infection control practices, and the responsible use of conventional and new broad-spectrum agents in hospital settings for more complicated infections caused by resistant bacteria.


The latest evidence suggests that prompt use of antibiotics that are effective against a wide variety of superbugs may reduce the seriousness of the disease, decrease the number of deaths and associated healthcare costs. The advantage of broad-spectrum antibiotics is that they can be used before the specific bacteria is identified, reducing delays in treatment while waiting for lab test results when time is of the utmost importance for the patient.

Community-Acquired MRSA also on the rise

Another disturbing trend reflected in the CAN-ICU study is the appearance of community-acquired MRSA (CA-MRSA) in Canada. Most antibiotic-resistant infections are acquired in hospitals, but recently CA-MRSA has been seen among athletes, soldiers, and I.V. drug users with treatment-resistant skin infections and pneumonia. CAN-ICU identified at least seven cases of CA-MRSA, which is primarily found in I.V. drug users and First Nations people being treated in Canadian ICUs.

"In Canada, sporadic cases of CA-MRSA have started to appear over the last decade. They tend to involve different strains and different antibiotic resistance profiles than hospital-acquired MRSA infections," says Dr. Tony Mazzulli, Medical Microbiologist and Infectious Diseases Specialist, and Professor, Department of Laboratory Medicine and Pathobiology, University of Toronto. "CAN-ICU is showing us that we need to focus our attention on a multi-pronged approach to reducing antimicrobial resistance within our hospitals, so that we are better prepared to fight off organisms that are finding a new battle ground in the community."

"Our research in the CAN-ICU study is telling us that we need a new, more aggressive approach to treating these superbugs; hit them early, hit them right and hit them hard, then de-escalate," says Dr. Zhanel. "New treatment options, including broad-spectrum antibiotics, will play an important role in dealing with superbugs."

To date, investigators in the CAN-ICU study have examined a total of 4,180 specimens from patients in 19 ICUs across Canada and have found higher than expected levels of antibiotic resistance in a range of virulent bacteria analyzed. The surveillance study provides an accurate view of resistant bacteria in ICUs across the country, as well as characterizing the profiles of these resistant strains. This information will be crucial as hospitals across Canada attempt to combat this resistance through aggressive infection control measures.