02/13/2015 10:14 EST | Updated 02/13/2015 10:59 EST

A Canadian Poll On Vaccines Finds 2 Of 5 Canadians Question The Science

Peter Dazeley via Getty Images
Girl (5-7) being given injection by doctor wiping arm with swab

A new national poll that mines attitudes toward vaccinations suggests support for these disease prevention tools remains relatively high in Canada.

But if you look beyond the over-arching numbers — nearly nine out of 10 people polled believe vaccination protects against disease — it contains figures that hint that support is less than optimal and potentially softening, said Dr. Kumanan Wilson, a researcher who has studied the phenomenon of vaccine rejection.

"If those numbers drop any lower, we're starting to get into worrisome range. And the trend doesn't seem to be in the right direction," said Wilson, a physician at the Ottawa Hospital.

The online poll was conducted by the Angus Reid Institute, a non-profit group that paid for the poll itself. It is based on the views of 1,509 Canadian adults who answered questions between Feb. 9 and 11.

The polling industry's professional body, the Marketing Research and Intelligence Association, says online surveys cannot be assigned a margin of error as they are not a random sample and therefore are not necessarily representative of the whole population.

The poll comes at a time when the debate over vaccination is heated, with measles outbreaks in Quebec and Ontario and a large outbreak in the United States that was sparked by exposures at California's Disneyland theme parks.

Adults 55 and older who took part in the survey were strongly pro-vaccine and tended also to support making vaccination mandatory for children to enter school. But younger adults seemed more ambivalent about these tools, which are widely credited as one of medicine's greatest advances.

Nine per cent of respondents in the 18-to-34 year old range described themselves as vaccine opponents and 26 per cent in that age group classified themselves as being on the fence. For respondents aged 35 to 54, those figures were five per cent and 16 per cent respectively.

Those numbers are concerning because it is people in those age groups who are likely to have children and who are deciding whether or not to vaccinate them. People 55 and older may be pro-vaccination, but those views aren't likely to translate into more vaccinated toddlers or elementary school students.

"That's a worrisome trend, that the younger people are less supportive than the older people," Wilson said.

Two out of five respondents agreed with the statement that "the science on vaccinations isn't quite clear." And eight per cent strongly agreed with the idea that there may be a risk of serious side-effects from vaccination.

Still, Shachi Kurl, the Angus Reid Institute's senior vice-president, saw the poll's numbers in a mainly positive light.

"What we find broadly overall is that Canadians are saying that vaccines are effective when it comes to preventing disease in individuals and in the community — nearly nine in 10 of them," she said.

In fact, 88 per cent of respondents agreed vaccines prevent disease for the individual and 86 per cent agreed they prevent disease in the population as a whole. Of the parents among the respondents, 83 per cent said they would definitely vaccinate their own children.

But those percentages hint at support that isn't sufficient to maintain herd immunity — enough protection in the community so that diseases like measles, mumps and chickenpox are unable to circulate.

"I think the 83 per cent would definitely vaccinate is a concerning number," Wilson said. "With the strength of science and the benefits of vaccination, you would hope that number would be much higher."

The numbers in the poll also capture the growing polarization of society on the issue of vaccinations. While 74 per cent of all respondents said it was irresponsible not the vaccinate children, only 56 per cent of respondents who were parents of school-aged kids believed children should be required to be vaccinated to start school.

The poll did not ask whether parents should be allowed to opt out for religious and philosophical reasons, which makes it hard to interpret how firm the support a mandatory vaccination policy actually is, Wilson noted. And he said going the mandatory route would only harden the views of vaccine opponents.

"If you make it mandatory, people will just opt out of the school system," he said, suggesting they would home school or cluster together and form their own daycares.

"You can't just make this thing go away. You have to figure out how to communicate with these people. I think that's the real message here."