A new, more lethal strain of a common bacterium is responsible for the deaths of hundreds of hospital patients in Quebec during the past year, health officials said yesterday.
New data, obtained by the Radio-Canada TV network, showed that there were 7,000 infections involving Clostridium difficile from April of 2003 to April of 2004. More than 600 of those cases were fatal, the report said.
The death rate, 8.5 per cent, is markedly higher than in the past. C. difficile usually claims the life of less than 1.5 per cent of those infected.
The infection rate, which usually hovers around 6 per 1,000 hospital admissions, has also soared to more than 30 per 1,000 in some Quebec hospitals, the province's Health Minister, Philippe Couillard, told reporters in Quebec City.
"A new strain has established itself," Vivian Loo, director of infection prevention and control at the McGill University Health Centre in Montreal, said at a news conference.
Dr. Loo conducted a study from January to June of 2004 that showed there were 700 cases of C. difficile in 10 hospitals. She discovered 109 deaths that occurred due to C. difficile and another 108 in which the bacterium contributed to death.
She said her findings about the new strain have been confirmed by the U.S. Centers for Disease Control. A number of hospitals in the United States and Canada have been hit by C. difficile outbreaks, but none has been as persistent or lethal as the outbreak in hospitals in Montreal and Sherbrooke, Que.
C. difficile is a common bacterium that usually poses no threat to healthy people, but can be dangerous to hospital patients being treated with antibiotics. The drugs alter the balance of bacteria in the intestinal tract, allowing C. difficile to flourish. The illness makes the intestines leaky and gives patients severe diarrhea.
Mr. Couillard said the new strain of bacterium is a "serious threat" to patients in affected hospitals but tried to reassure the public that the worst of the outbreak has passed.
"I want to tell the population and all those working in hospitals that Quebec is doing everything it can to limit to a maximum and even reduce the extent of this scourge in our hospitals," Mr. Couillard said.
He said that since the data were collected, the rate of C. difficile had fallen in hospitals and more measures would be taken to limit its spread.
Charles Frenette, chief of microbiology at Charles LeMoyne Hospital in Greenfield Park, Que., said there are four well-established ways of fighting the spread of C. difficile: Isolate infected patients, thoroughly clean and disinfect rooms, promote hand-washing among hospital staff and prescribe antibiotics judiciously.
Richard Zoutman, a professor in the school of medicine at Queen's University in Kingston and an expert in infection control, said the persistence and severity of C. difficile in Quebec hospitals is extremely worrisome.
"Everybody in the infectious diseases community should stand up and take notice of what's happening in Quebec," he said in an interview.
Public health officials from across Canada will meet in Ottawa Thursday to discuss the increasingly worrisome problem of C. difficile.
André Picard
Rhéal Séguin