TORONTO — A choir of voices is calling for Canada to speed up the start
of its pandemic flu vaccination program. Interestingly, though, some of the
country's leading public health and infectious diseases experts aren't singing
the same tune.
A number of them say the benefits that might be gained from releasing pandemic
vaccine under emergency use provisions may not be worth the risk of sowing
distrust of the vaccine among members of the public.
"This is a real tightrope walk," says Dr. Michael Gardam, director of infectious
diseases prevention and control at the Ontario Agency for Health Protection and
Promotion.
"Because given it's a new virus vaccine, given it's an adjuvant we haven't used
before, given the disease is relatively mild, I want to feel confident that when
we roll out the vaccine that the checks and balances are in place and that we've
got decent safety data and decent efficacy data before it goes out."
"And that is why in my mind... I have come down on the side of 'Let's by all
means get this out and let's offer this to people. And let's make sure we've
crossed our T's and dotted our I's before we do it."'
Dr. Donald Low, a leading figure in Canada's response to the 2003 SARS crisis,
shares that view. He points to the high degree of public awareness of the 1976
swine flu affair.
That event, which casts a long shadow over the response to this pandemic, saw
more than 40 million Americans vaccinated against a pandemic that never
materialize. For reasons that still aren't understood, the vaccine seemed to
trigger 500 cases of the paralytic condition Guillain-Barre syndrome and about
25 deaths.
Experts expect this vaccine to be as safe as seasonal flu vaccine. But they know
that if problems were to arise, particularly in a vaccine the public perceived
to have been sped through licensure, that would have enormous consequences - and
not just for future flu shot campaigns. The burgeoning anti-vaccination movement
has swine flu vaccine in the cross-hairs.
"I think that you want to make sure that you're doing this right. And to rush
things and take short cuts and make a mistake, the damage would last for a long,
long time," says Low, chief of microbiology at Toronto's Mount Sinai Hospital.
"They have to really be cautious," he says of the federal government. "You can't
sort of just rush it without a lot of thought."
Low notes Canada has alternatives in its pandemic flu arsenal - millions of
stockpiled treatment courses of Tamiflu and Relenza, another antiviral drug.
"You've got something to fall back on here. It's not like you don't have
anything."
Despite internationally acknowledged foresight, years of planning and tons of
hard work on the part of officials of both Health Canada (the regulatory arm)
and the Public Health Agency of Canada, this country seems poised to start
vaccinating against the swine flu virus weeks after the Americans, the Chinese
and some European countries.
China has already started to immunize. Australia will begin on Sept. 30. In the
U.S., officials said Friday they will send out 3.4 million doses of vaccine to
states at the beginning of October; by mid next month, 20 million doses a week
will be in the distribution pipeline.
As things stand, the first Canadians will be vaccinated in mid-November. Dr.
David Butler-Jones, head of the Public Health Agency of Canada, has said that
date could conceivably be pushed up a little, if the risks from the virus seemed
to be outweighing the benefits of giving the vaccine full approval.
With flu activity in the United States already gaining steam, many experts south
of the border have warned even the U.S. effort might be too late to have a real
impact on the second wave of the pandemic in that country.
The immune system needs at least eight to 10 days to work up protective levels
of antibodies after novel H1N1 vaccine is given. And a wave of flu activity in a
given community lasts about seven weeks, but peaks about Week 4.
Though influenza is mercurial and defies prediction, if the U.S. is gripped by
widespread flu activity a couple of weeks from now it's hard to imagine at least
parts of Canada won't be as well.
Canadians authorities are under pressure to speed up release of the vaccine. In
the House of Commons on Friday, opposition MPs hammered the government for
moving too slowly. And the Canadian Medical Association Journal has called for
expedited access to vaccine for people at high risk of complications or death
from the flu, such as pregnant women.
The journal's editor, Dr. Paul Hebert, is an intensive care doctor who has
treated gravely ill swine flu patients. He admits that experience is influencing
his position on further fast-tracking the pandemic vaccine.
But experts from other parts of the medical community look at things differently
as they try to find the sweet spot between speed, vaccine safety and public
acceptance.
"The people who are charged with making a decision about whether there's going
to be emergency release or not will have to make a judgment call about whether
the potential risks of an interim authorization order, the emergency release,
are worth it given where the pandemic is in different parts of the country when
it happens," says Dr. Allison McGeer, an influenza expert and head of infection
control at Mount Sinai Hospital.
Generally speaking public health and infectious diseases experts are keen
proponents of flu shots. But they also know that this virus isn't mowing people
down left, right and centre. If it were, there'd be no discussion of crossing
T's and dotting I's.
"At the moment we're agonizing about a situation in which in fact the risks are
not enormous," McGeer says. "This is a good pandemic as pandemics go."
A public health researcher who has done a lot of work on the anti-vaccination
movement says that's probably factoring heavily into the federal decision
making.
"We don't know how bad this thing's going to be and it may not be very bad at
all," says Dr. Kumanan Wilson of the Ottawa Hospital Research Institute.
"And do you want to aggressively accelerate the safety assessment of the vaccine
to get it out in time for something that may not be a big deal? So I think what
they're doing is they're doing a 'wait and see,' he says of federal officials.
"And if it does look like something more significant than perhaps what we might
otherwise have anticipated is going to happen, they could accelerate that.""
"What they don't want do, I think, is push this vaccine aggressively, release it
too early, have adverse events and find out that there really wasn't that big a
deal. Because that will undermine all subsequent campaigns."
-Follow Canadian Press Medical Writer Helen Branswell's flu updates on Twitter
at CP-Branswell
Source : The Canadian Press
