An estimated 30 to 35 per cent of Canadians have been immunized against H1N1. (Darren Calabrese/Canadian Press)

There were far fewer swine flu deaths across the country in the Public Health Agency of Canada's most recent reporting period.

For the five days ended Tuesday, six H1N1 deaths were reported, in British Columbia, Alberta, Quebec, and Newfoundland and Labrador, the agency's latest figures show.

In comparison, there were 28 swine flu deaths between Nov. 26 and last Thursday.

The total number of deaths due to H1N1 in Canada since the influenza pandemic emerged in the spring is 363, the health agency said.

2nd wave differs

For the week ended Nov. 29, there were fewer cases, hospitalizations and deaths, but the intensity of flu activity was still moderate, Canada's chief public health officer, Dr. David Butler-Jones, told reporters on Wednesday.

Compared with the first wave of cases in the spring, so far in the second wave there have been 4½ times more hospitalized cases and 3½ times more deaths, Butler-Jones noted.

Regardless of whether a peak has been reached, people who are not vaccinated risk getting sick and spreading the virus to others, said Health Minister Leona Aglukkaq.

It's estimated that 30 to 35 per cent of Canadians have been immunized against H1N1, and that vaccination rates in provinces and territories range from 25 per cent to 67 per cent, Aglukkaq said.

Federal health officials had hoped that everyone who wanted to be immunized would receive the shot by the end of December.

Critics say more haven't been vaccinated because a lot of people wanted the vaccine early on when most family doctors weren't given much to administer.

"When you hear that people are waiting for three hours, you say, 'Forget it, you will get it another time, I will do it another time,' and then they say, 'Forget it, it's over,'" said Dr. Yoel Abells of the Forest Hill Family Health Centre in Toronto.

Vaccine supplies

Aglukkaq also announced the launch of a national TV advertising campaign on the importance of the H1N1 vaccine, which will run into early January.

"There are critics who say mass vaccinations should not continue, and Canadians who think we've reached a critical mass already of people vaccinated," Butler-Jones said. "I question that logic."

The current swine flu pandemic may mirror the 1957-58 pandemic that saw another peak of infections just before spring, he said.

As mass immunizations clinics for H1N1 wind down in some cities, the vaccine continues to be available at doctors' offices.

Since the vaccine has a shelf life of 18 months if stored correctly, unused vaccine could last well into next year's flu season, federal health officials said.

By the end of this week, nearly 24 million doses of the vaccine will have been shipped to provinces and territories. Canada ordered 50.4 million doses when it was thought adults might need two doses.

While many other developed countries have pledged vaccine to the World Health Organization for redistribution to developing countries, federal health officials have not yet said what they will do with excess vaccine.

"Vaccine will not be wasted," Butler-Jones said, noting discussions are ongoing about offering surplus supplies to poorer countries, including those in the Southern Hemisphere, where the flu season is the opposite of Canada's. "There's a tremendous demand around the world."

The timing of the use of the vaccine is key, said Dr. Michael Gardam, director of infectious disease prevention and control at the Ontario Agency for Health Protection and Promotion in Toronto.

"To do this to help other countries is a great thing, and Canada has a long tradition of doing that sort of thing," said Gardam. "But you want to give something which is relevant to the people you are giving it to, so if you are going to donate it, you want to donate it as quickly as possible."

Federal health officials plan to make a decision about what do with leftover vaccine in about two weeks. Options include selling some to countries such as the U.S., or donating the bulk to WHO to pass on to developing countries.

Cases in North Korea

Elsewhere, North Korea acknowledged an H1N1 outbreak for the first time. State media reported Wednesday on nine confirmed cases in northwestern Sinuiju along the Chinese border, and in Pyongyang, the capital.

The World Health Organization, which has an office in Pyongyang, said in a statement that no deaths due to swine flu had been recorded in North Korea, and added that "active surveillance" was underway to contain the spread of the virus.

At least 8,769 people worldwide have died from H1N1 since April, according to the WHO.

The death estimates are based on laboratory-confirmed deaths, which experts say are likely to be an underestimate of the total toll of the disease.

With files from The Associated Press