The researchers found that the universal vaccine program prevented about 61 per cent of flu cases each season.
For a few weeks last autumn, fear of pandemic influenza stalked the land. Death seemed to lurk around every corner. A sneeze in public could draw a reproachful glance, and every handshake sent the anxious fumbling for their hand sanitizer. Gradually, the panic subsided, to be replaced by confusion over all the fuss made by governments and public-health agencies
But the end of the H1N1 influenza pandemic is now in sight. Fear of H1N1 has now receded to the point that the World Health Organization is expecting to declare the pandemic over in the next week or so.
Dr. Margaret Chan, director general of the World Health Organization, said the panel of experts that advises the WHO is feeling increasingly confident H1N1, which has killed more than 18,000 people around the world, has taken on the characteristics of a typical seasonal flu.
"All in all, people feel that the overall picture looks like we are ready to declare post-pandemic globally very soon," Dr. Chan said.
Every pandemic eventually becomes a seasonal flu strain. This fall, when flu season arrives again, H1N1 will still be one of the major variants floating around, but the population has shown sufficient resistance to it that there have been very few new deaths or flu activity in Canada since February, according to Dr. Perry Kendall, British Columbia's provincial health officer.
As the end approaches for H1N1, many will wonder whether the panic was justified. Immunization programs in Canada had disappointing results, as a little more than 40 per cent of the population was immunized, compared to targets that approached 70 per cent. More than 400 Canadians died as a result of contracting H1N1 and about one in three Canadians were infected by the virus.
Dr. Kendall was one of the officials responsible for planning the response. He happened to be in Mexico when the outbreak began there in the spring of 2009, and flew home to high-level meetings to create the public health plan. Though the H1N1 virus was not as deadly as the 1918 Spanish flu, he said, there was no way of knowing that a year ago.
"You can't know in advance what the experience is going to be, particularly in vulnerable populations. That's like having a future-scope. There are some very scary influenza viruses out there," Dr. Kendall said, citing avian influenza, which kills 60 per cent of the people it infects.
"We were planning with [avian flu]and 1918 in mind, and that meant you had to develop a vaccine as quickly as possible. The lesson learned from this is that unless we get some radical new technologies we're not going to get an influenza vaccine within the first six months. That means for the first wave of the virus, there's going to be no vaccine to protect people."
It was just as the vaccine was ready to be made available in late October last year that a number of otherwise healthy young people in Ontario died, which sent a wave of fear through the population and brought huge crowds to the first vaccination clinics.
"That really triggered alarm bells," Dr. Kendall said. "Statistically it was bound to happen, but when it happens in a large community like Metro Toronto, people get very worried, understandably."
There was debate about who should be vaccinated first, front-line health care workers or those with health conditions that made them vulnerable. And there was outrage over queue-jumping, particularly allegations that professional sports teams received preferential treatment. But by Christmas the fear seemed to have subsided, Dr. Kendall said. At that point there was plenty of vaccine, but no one wanted it. Many felt that too much fear had been generated over a virus that didn't prove anywhere near as deadly as feared.
"We planned for the worst-case scenario," Dr. Chan said. "If there's something we can do better...I think we would advise people in pandemic preparedness planning in future [that]we should look at the best case scenario, the intermediate case scenario and the worst case scenario.
"That would provide us flexibility to move up and down the scale."
The pandemic's end will be declared as it takes its second tour of winter in the Southern Hemisphere. So far there has been evidence the intensity of outbreaks has been reduced and the virus is no longer as dominant as it once was.
With a report from The Canadian Press
Joe Friesen