1 million H1N1 cases averted in Ontario

Ontario’s H1N1 vaccination program averted nearly one million cases and as many as 50 deaths, a newly published cost-analysis of the program suggests.

TORONTO — Ontario’s H1N1 vaccination program averted nearly one million cases and as many as 50 deaths, a newly published cost-analysis of the program suggests.

The finding is surprising, given that the province — and the country — started putting vaccine into arms just about the time the fall wave of the pandemic peaked.

One of the authors of the study said she expected to see that the mass vaccination effort wouldn’t have had much of an impact on the second wave, because of how long it took to make the vaccine and get it to delivery sites.

“I was surprised, but you know I shouldn’t have been. Because we know over and over again that vaccination programs are effective and cost effective,” said Dr. Allison McGeer, an influenza expert at Toronto’s Mount Sinai Hospital.

“The truth of the matter is that we had a week to make a difference when the vaccine was first out. And after the first week of the vaccine campaign, nothing we did made very much difference,” she continued.

The study, which was published in the journal Vaccine, was made public Monday — the same day Statistics Canada released the first official national estimates of how many Canadians were vaccinated against H1N1 last fall and early winter.

The findings, drawn from the 2010 Canadian Community Health Survey, suggest that 41 per cent of Canadians over age 12 got an H1N1 vaccine shot.

The total national figure is likely somewhat higher. For one thing, the report did not include people living in the northern territories, where earlier this year uptake was estimated to be over 60 per cent in Nunavut and Northwest Territories and about 53 per cent in Yukon.

As well, the figure doesn’t include children under 12. The vaccine was recommended for children six months and older.

The Statistics Canada study suggested Ontario had the lowest rate of vaccination, coming in at about 32 per cent of the population over age 12. Newfoundland and Labrador was highest, at 69 per cent. Most provinces were above 40 per cent.

Even with the relatively low uptake, the Ontario program was cost effective, according to the Vaccine study, which was led by Beate Sander.

Sander, who is now a health economist with the Ontario Agency of Health Protection and Promotion, did the work as part of her doctorate at the University of Toronto, before she joined the Ontario agency.

She and her colleagues used a disease transmission model to predict what would have happened if no intervention had been used to prevent the spread and impact of the flu.

They then compared those rates to the actual reported number of hospitalizations, emergency department visits and deaths.

“At $180 million, it was a costly program, but it was also highly cost effective,” she said.

Sander and her co-authors said Ontario could have seen an additional 420 hospitalizations, 28,000 visits to hospital emergency departments and 100,000 visits to doctors’ offices if it hadn’t offered the flu shot program.

She noted that if the vaccine had arrived any later the program wouldn’t have been as cost-effective as it was. Conversely, the program might have been more cost effective if Ontario had managed to vaccinate more people.

A report on the province’s pandemic response released last month by Dr. Arlene King, Ontario’s chief medical officer of health, put the disappointing vaccination rates down to the fact that there was never a match between public demand and availability. When the public wanted shots, there were either none or too few available. When vaccine was plentiful, the threat had subsided and the public was no longer interested.

But that would have been the case in other provinces too and they managed to get more residents vaccinated. McGeer said public health officials need to learn what worked, so they can adjust plans for the next time mass vaccination is required.

One of the programs that would be important to study would be Newfoundland’s, she suggested.

“Very clearly they were head and shoulders above everybody in vaccine delivery and there are clearly some lessons for all of the rest of us in how they managed to do that.”

In general, Atlantic Canadian vaccination efforts were quite successful. Prince Edward Island and New Brunswick vaccinated 62 per cent of their residents; Nova Scotia reached the 58 per cent mark. Quebec also vaccinated 58 per cent of its population.

In the West, Saskatchewan tallied 46 per cent, with Alberta and Manitoba vaccinating 37 per cent of their residents, and British Columbia at 36 per cent.