Health officials say they expect to have enough swine flu vaccine to immunize all Canadians who want it by late fall, and a list of priority groups should be ready by September.

The company that's producing the vaccine for Canada, GlaxoSmithKline, should start clinical trials by October at the latest, Health Minister Leona Aglukkaq told a news conference on Wednesday afternoon.

She added that health care officials are working on a list of groups who ought to be vaccinated first.

"Decisions on priority access will reflect the principles of the Canadian pandemic preparedness plan," and will be based on "the best available" scientific evidence, Aglukkaq said.

The list of priority groups should be drawn up by September, officials said.

"For us it won't be whether they're immunized or not. It will be whether they're immunized or not today, when it comes to that time, or three weeks or four weeks later," said Dr. David Butler-Jones, head of the Public Health Agency of Canada.

The federal government signed a deal with GlaxoSmithKline in 2001, under whose terms the company is to produce enough vaccine for everyone in the country in the event of a pandemic threat.

Aglukkaq and Butler-Jones announced that new guidelines are to be released outlining how health care workers should protect themselves when dealing with flu patients as well.

"One of the goals here is to keep these facilities completely free of the influenza virus in the first place," Butler-Jones said.

U.S. vaccine-plan update

South of the border, the Centers for Disease Control and Prevention in Atlanta said it would focus its vaccination programs on five groups which face a greater risk of serious illness.

The groups include:

  • Pregnant women
  • People who live in homes with children under the age of six
  • Health workers and emergency personnel
  • People from six-months-old to 24-years-old
  • Non-elderly people with underlying health problems

While there has been concern about the vaccine's delivery, the CDC said its program should be up and running by the fall.

Still, CDC spokeswoman Dr. Anne Schuchat, who oversees the CDC's flu vaccination programs, said that setting an exact delivery date for the vaccine and knowing exactly how much will be available is difficult.

"As we've been telling you, with influenza vaccines -- whether they're seasonal or this new H1N1 vaccine -- production can be unpredictable," she said Wednesday afternoon.

"Right now we are on track, expecting vaccine doses in the fall. Exactly how many, exactly when, will be tough to pinpoint."

With files from The Canadian Press