The Canadian Press, October 1, 2007
CANADA'S BLOOD SUPPLY 'SAFE AS ANYWHERE,' SAYS AGENCY'S CEO
[Rachel's introduction: Both Canadian Blood Services and Hema-Quebec, its Quebec equivalent, use what's known as the precautionary principle when making decisions about blood safety issues. In essence, the precautionary principle means that when there are two or more possible courses of action, the choice should be the option that affords the greatest safety -- even in the face of small risk.]
TORONTO -- Canadians who need blood or blood products are safer as a consequence of measures taken in the aftermath of the tainted blood scandal, a tragedy which led to the revamping of the blood collection and transfusion system in this country, the head of the agency responsible for the blood service said Monday.
"The legacy of the tainted blood scandal has been very profound, in this country and even internationally," Dr. Graham Sher, CEO of Canadian Blood Services, said in an interview from Ottawa.
Sher wouldn't comment on an Ontario Superior Court ruling acquitting Dr. Roger Perrault, the former national medical director of the Canadian Red Cross, and three other doctors of criminal charges related to the scandal.
But he stressed that there are many more checks in place today to protect recipients of blood transfusions or blood products from bloodborne disease agents, known and unknown.
Still, there is no way to ensure that donated blood is risk-free. Sher insisted: "We've never claimed that it's risk free."
"Our job is to make that risk as low as possible and we've been extremely successful at that," he said.
"And then the physician must always counsel his or her patient before a transfusion in terms of what are the risks and what is the benefit. And you don't get a transfusion unless you absolutely need one."
Sher said both Canadian Blood Services and Hema-Quebec, its Quebec equivalent, follow the recommendations of the Krever Inquiry and use what's known as the precautionary principle when making decisions about blood safety issues.
In essence, the precautionary principle means that when there are two or more possible courses of action, the choice should be the option that affords the greatest safety -- even in the face of small risk.
When the blood services learned that the West Nile virus could be transmitted in blood they worked with the pharmaceutical industry to ensure rapid development and deployment of tests. This summer -- the worst ever for West Nile infections in this country -- Canadian Blood Services found and removed from the blood system 70 blood donations contaminated with the virus.
A second layer of tests has been put in place for HIV and hepatitis B and C, Sher added.
And when scientists at the Public Health Agency of Canada discovered that simian foamy virus can be transmitted through blood, the blood services added a question to their blood clinic screening questionnaire aimed at excluding would-be donors who work with or have contact with primates.
There is currently no test for simian foamy virus, a retrovirus from the same class of viruses as the human immunodeficiency virus (HIV). Common in some primates, the virus isn't believed to cause disease in humans. But diseases caused by retroviruses can take a long time to develop, and the blood services don't want to take chances, Sher said.
"That's a very good example of where we've applied the precautionary principle. In fact... we're the only two blood systems in the world - the two Canadian blood services -- that have a measure in place to ask donors about exposure to certain types of primates."
The agencies are currently studying the potential threat posed to the blood system by Chagas disease, caused by a parasite rarely found in Canada but more commonly found in Central and South America. The agency believes it may have a test in place for Chagas in 2008.
As another precaution, Canadian Blood Services filters white cells out of the blood donated to it. White blood cells are immune system soldiers and can harbour pathogens. They aren't needed for blood products, Sher said, and it is safer to remove them.
"It's one way of lowering the risk to the recipients," he said, noting the agency is one of few in the world that takes this added step.
Copyright 2007 The Canadian Press