Superbugs, powerful drug-resistant bacteria, are more common than thought, a survey of 20 hospitals across Canada shows.

Wednesday's report by the Canadian National Intensive Care Unit is part of an ongoing surveillance of the infections.

The study's authors said the results show the importance of:

• Diligent infection control.
• Appropriate prescribing by doctors.
• Patients following instructions, such as taking the full course of antibiotics to help prevent resistance.
• Responsible use of antibiotics in hospitals for more complicated infections caused by resistant bacteria.
• New treatment options.

Complications from the infections such as methicillin-resistant Staphylococcus aureus (MRSA) kill 8,500 Canadians each year, according to the Community and Hospital Infection Control Association.

"The stark reality in this country today is that MRSA and other drug-resistant bacteria are posing a serious threat to our ICUs," said Dr. George Zhanel, the study's lead investigator and a professor in medical microbiology 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."

Staph bacteria are commonly found on the skin and in the noses of healthy people, but they can cause infection when entering the body through a cut or during surgery.

In a cross-Canada study of hospital-acquired cases of staph infection, an average of 20 per cent of the bacteria were resistant to the antibiotic methicillin. The highest incidence of resistance recorded at a hospital in the country was 50 per cent. 

Previous estimates indicated up to 15 per cent of staph bacteria were resistant to the drug.

Researchers were disturbed to discover a small number of cases of MRSA acquired in the community, as opposed to in hospital. Examples found have included resistant cases of skin infections or pneumonia among athletes, soldiers, IV drug users and First Nations people — some of whom ultimately needed to be treated in intensive care.

The seven community-acquired cases tended to be different from the hospital-acquired strains and were resistant to different types of antibiotics, said Dr. Tony Mazzulli, a medical microbiologist and infectious disease specialist at the University of Toronto.

The study was sponsored by the drug company Wyeth, which is developing a new antibiotic.