A nurse stores prepared syringes of H1N1 flu vaccine in a fridge at a Toronto clinic. (Darren Calabrese/Canadian Press)

All people in Ontario will be offered the H1N1 vaccine as of Thursday, the province's health minister said Wednesday.

"Today's announcement will apply to all health units across Ontario, even though a number of health units began to immunize members of the general population earlier because they had the capacity and vaccine supply to do it," Deb Matthews told a news conference in Toronto.

The decision was made because Ontario is now confident it has enough vaccine and people to roll it out.

It's the largest immunization campaign held in the province, with 2.5 million people vaccinated in three weeks.

Until now, Ontario was reserving vaccine for members of priority groups such as health-care workers, pregnant women, children and people with underlying medical conditions.

This week, at least 17 health units in the province began offering the swine flu vaccine to the general public. Mass immunization clinics in the Toronto area opened to all on Wednesday.

Matthews thanked people for their patience and noted that not everyone will be able to get the shots at the same time.

Flu activity still high

But it is not too late to be immunized, said Dr. Vikek Goel of the Ontario Public Health Agency.

Flu activity is still high in many areas of the province — more than double what public health officials have seen in past flu seasons, said Arlene King, Ontario's chief medical officer of health.

Since April, there have been 76 lab-confirmed deaths linked to H1N1 in Ontario. The province has 213 confirmed cases in hospital, with 82 in intensive care, King said.

It's expected the virus will continue to circulate for at least the duration of this flu season, she said.

Vaccine interest wanes

Also on Wednesday, Manitoba's government announced it will offer H1N1 vaccinations to all residents, effective immediately.

At a flu shot clinic in downtown Toronto, lineups took about one hour to 80 minutes on Wednesday.

In St. Catharines, Ont., Dr. Robin Williams, the region's medical officer of health, is keeping a nervous eye on clinic lineups in her area.

"We have just seen a decreased appetite for vaccination," said Williams. "We're no longer on the front of the news. I think people are losing their energy and interest in it."

Public health officials aim to vaccinate 50 to 70 per cent of the population to stop the spread of the virus.

"We serve the three-fold purpose of protecting ourselves, those close to us and our communities by being immunized," said King. "So I think it's not only an individual intervention but it's also very much a societal intervention and contribution as well."

Nunavut has immunized about 60 per cent of its population, Dr. David Butler-Jones, Canada's chief medical officer of health, told the parliamentary health committee on Wednesday.