TORONTO - In the race to get pandemic vaccine into Canadian arms, public health and vaccine regulatory authorities in this country find themselves the reluctant filling in a rock-and-a-hard-place sandwich, knowledgeable observers say.

Doctors who've seen how desperately sick some swine flu patients become are pressing authorities to further fast-track vaccine approval. But a large portion of the public appears reluctant to take the vaccine, a situation that could worsen if fast-tracking deepens suspicions about the product's safety.

Individuals and organizations concerned about global equity are urging countries with vaccine contracts to stretch supplies by using boosting compounds called adjuvants so developing countries can also get some serum. But the decision to use an adjuvant is being blamed - unfairly, federal officials say - for the fact Canada may not start vaccinating until a month after the U.S. and Britain.

Dr. Ross Upshur, director of the University of Toronto's Joint Centre for Bioethics, sums up the dilemma that federal authorities managing the pandemic vaccine file face.

"They're going to get enough vaccine for everybody to have it; nobody's going to want it, and any sequence that they can come up with of who gets it first isn't going to satisfy anybody because somebody has to go second for a vaccine that they don't want to get," Upshur says.

"They can't win," agrees Dr. Marie-Paule Kieny, head of the World Health Organization's vaccine research initiative.

The WHO had asked countries with first access to pandemic shots to employ vaccine sparing approaches, such as the use of adjuvants, so that there will be more to go around. Without frugal use in wealthy countries, the vast majority of nations will have limited access, at best, to vaccine against the novel H1N1 virus.

Kieny, who is based in Geneva, has watched the Canadian debate unfold from afar.

"They have thought it would be better to have with adjuvant and they could well be right," she says. Kieny notes that with an adjuvant, the vaccine should protect against not only the current viruses, but those that are expected to start to circulate as the virus evolves or "drifts" as that process is called in flu science.

"If the strain drifts - which we don't know, but may well be the case - then with adjuvant would be preferable," she says. "I think it was a sensible decision to make."

In the United States where the 1976 swine flu incident is looming large over the response to this perplexing pandemic, authorities have opted for caution. In 1976, a feared pandemic with a swine flu virus didn't materialize. But elevated rates of the sometimes fatal Guillain-Barre syndrome emerged among the more than 40 million vaccinees.

U.S. authorities have made it clear they will only use adjuvanted vaccine if their supplies won't meet American needs. They will not use the boosting compounds to stretch supplies for the developing world.

That position has also drawn fire, including by the head of the Gates Foundation's global health program.

In a commentary published in the New England Journal of Medicine, Dr. Tachi Yamada said it would be inexcusable for people in poorer countries to die because richer countries use up most of the limited vaccine supplies. And he specifically pointed to the reluctance to use adjuvanted vaccines, currently licensed in parts of Europe but not in North America.

"Under a global health crisis where millions could die we have to really think hard whether we play by the rules we establish for normal times, or we think much more aggressively and take greater risks," he said in an interview last month.

But people in this country who fear Canada's supplies will arrive too late to prevent a possible surge in severe cases in the early fall contend the inclusion of an adjuvant is dragging out the approval process.

In an editorial published last week, the Canadian Medical Association Journal called on the federal government to offer unadjuvanted vaccine to people at high risk of having life-threatening bouts of flu, and to make it available sooner.

Editor-in-chief Dr. Paul Hebert, who signed the editorial, is an intensive care physician in Ottawa. He admits his experience treating gravely ill swine flu patients is framing his position on the issue.

But conflicting views even within the journal illustrate the dilemma federal officials face.

Earlier in the summer Dr. Amir Attaran, the journal's associate editor for editorials, co-authored an editorial arguing that pandemic vaccine must be shared equitably globally.

Attaran, who is taking a break from the editorial team until the end of the year, says if he'd been there he would have argued against the call to use unadjuvanted vaccine.

"We're in this domain where there can be disagreements among well-intentioned, knowledgeable people sharing the same goal, and yet it is not possible to say who is right or wrong," he says.

Federal officials, who have faced a barrage of questions about why Canada's program would start later than those of other countries, have tried for days to shake the perception that adjuvant is the enemy of speed.

"Whether it's adjuvanted or unadjuvanted, it doesn't matter. It did not delay the process at all," insists Dr. David Bulter-Jones, the country's chief public health officer.

He says there are ways to bring the program forward, but they involve doing less study of the safety and effectiveness of the vaccine.

Those compromises might be warranted if flu activity starts earlier than the typical seasonal pattern, where the worst of the illness comes after Christmas, or if the proportion of severe cases starts to mount, Butler-Jones says.

But they might come at a cost in terms of public acceptance of the vaccine. The vaccine skeptics have the pandemic flu shots firmly in their sights.

"There's definitely anxiety and concern," says Jennifer Keelan, a public health researcher at the University of Toronto who studies trends in vaccine acceptance and monitors the Internet's heated discourse on vaccines.

"People keep talking about the rapid deployment of this vaccine.... 'Why are we hastening when it's not 100 per cent clear what the actual risks are from this infection?"'

The U.S. vaccine resistance group the National Vaccine Information Center, for instance, says it's now obvious swine flu is no more serious than garden variety flu and it argues "fast-tracked" and "experimental" swine flu vaccines will end up being riskier for children than catching the virus.

Keelan, who says American and Canadian attitudes on pandemic vaccine seem closely aligned, notes a recent public consultation process undertaken by the U.S. Centers for Disease Control found participants were concerned about the use of the preservative thimerosol, the possible use of adjuvants and the adequacy of testing.

By the end of one day-long discussion, 49 per cent of the participants favoured a "moderate effort" approach to vaccine roll out and 30 per cent preferred a "go slow" approach.

Only 21 per cent supported going "full throttle" on pandemic vacccine.

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