Two million doses of the swine flu vaccine have been shipped to the provinces and territories, the federal government announced Monday, with more expected to be ready in the coming days.

The vaccine is in full production by its maker, GlaxoSmithKline, and clinical trials are well underway, Health Minister Leona Aglukkaq told an Ottawa news conference.

"As the vaccine rolls off the production line, it is being shipped to locations across the country," Aglukkaq said. "Of course it will be released once it has completed the approval process, and that process is well underway."

Aglukkaq and Dr. David Butler-Jones, Canada's chief public health officer, would not confirm reports that the government will approve the vaccine within the next few days.

If so, that would mean some Canadians could potentially be vaccinated by the end of the week.

"Given we're within a very short period to the time that we've always talked about being ready before the beginning of November, I think it's important that we get the assurance from the regulator about the confidence in the safety and effectiveness of the vaccine," Butler-Jones said.

Health officials have ordered 50.4 million doses of the H1N1 vaccine, which contains an adjuvant additive, a compound that will make it more effective. Another 1.8 million doses of the vaccine without the adjuvant are also on the way.

This means all Canadians can have access to the vaccine, unlike in the United States, which has only about 40 million doses for a population of 300 million.

There has been some concern about the vaccine containing the adjuvant, because Canada has never approved an adjuvant-containing flu vaccine before.

Butler-Jones described the adjuvant as a natural product of fish oil, water and vitamin E, and said it will allow the vaccine to offer protection even if the H1N1 virus mutates.

While pregnant women have been encouraged to receive the vaccine that does not contain the adjuvant, Butler-Jones said, the vaccine with adjuvant is still safe for expectant mothers.

"The risks to pregnant women from contracting H1N1 are much, much higher than any theoretical risk posed by adjuvanted vaccine," he said.

The vaccine without the adjuvant must be manufactured and packaged, and therefore shipped, separately. Butler-Jones could not say when the non-adjuvanted vaccine will be ready.

H1N1 now dominant flu virus

Earlier Monday, one health expert said time is of the essence when it comes to rolling out the swine flu vaccine, as H1N1 has squeezed out the seasonal flu as the dominant virus this year.

According to Dr. Michael Gardam, of the Ontario Agency for Health Protection and Promotion, 97 per cent of flu isolates are the H1N1 strain, meaning "there really isn't any seasonal flu right now."

Therefore, the swine flu vaccine must be rolled out as quickly as possible, Gardam says, so public health officials can stay ahead of the virus.

"Time is a factor just because we are seeing a fair amount of flu activity already in British Columbia, and we're certainly expecting to see a lot more of this happening in the rest of Canada in the coming weeks," Gardam said Monday in an interview with CTV News Channel.

"So we do want to get this moved out quickly. But the reality is that this is a flu shot, similar to any other flu shot that we've given, so it really comes down to the actual logistics of setting up the flu shot clinics and getting it into people's arms."

Gardam said Canadians have no reason to worry about receiving a vaccine that will have been developed, tested and approved within only a few months.

Many of the components of the vaccine are similar to those found in the seasonal vaccine, he said. And adjuvant vaccines are common in Europe.

"So there's nothing unduly suspicious or odd about this," Gardam said. "I think people should just get out there and get vaccinated, not so much because you're worried about being hospitalized from the flu, because the reality is that most people, if they are otherwise healthy, won't get hospitalized. This is more just about preventing you from being sick and on your back for several days."

Risks still unknown

Concerns have been raised about the new swine flu vaccine 30 years after a vaccine for a different strain of swine flu was given to millions of people across the United States.

That vaccine, administered in 1976, was linked in a small number of cases to a rare neurological condition called Guillain-Barre syndrome, which can lead to reversible, though sometimes fatal, paralysis.

Scientists did not conclusively prove the link, and according to infectious disease specialist Dr. Neil Rau, Canadians will learn in just a few weeks if fears about contracting the syndrome are warranted.

"We're going to probably be able to piggyback on the experience in the U.S. and Europe as they keep administering this vaccine and monitoring for this rare side effect," Rau told CTV News Channel on Monday afternoon. "So if two or three weeks have gone by and we don't see it, we'll know that at least two or three million people received the vaccine and we're not seeing it and I think we'll be able to breathe easier."