"A key step forward is to track immunization status from birth," said Colin Busby, co-author of "A Shot in the Arm: How to Improve Vaccination Policy in Canada."
The research paper released Thursday by the C.D. Howe Institute was funded by the economic think-tank and reviewed by immunization researchers, Busby said in an interview.
It finds that coverage across the country ranges from 70 to 95 per cent of children, depending on the vaccine.
Vaccination rates of about 95 per cent or more are generally considered ideal for a population to develop so-called protective "herd immunity."
Only Newfoundland and Labrador topped 95 per cent for all shots studied, including measles, mumps, chicken pox, diphtheria, tetanus and whooping cough.
"Importantly, at least by their own estimates, almost all provinces appear to be below national targets for coverage," the study says.
New Brunswick had 69 per cent coverage for measles, mumps and rubella, just ahead of Nova Scotia at 66 per cent — the lowest rates among provinces.
Saskatchewan and P.E.I. had 79 per cent coverage and Quebec just under 84 per cent.
Ontario had almost 91 per cent compared to 85 per cent in Alberta, 86 per cent in B.C. and almost 87 per cent in Manitoba.
Busby stressed that varied provincial reporting methods and major tracking gaps for preschool children restrict information available to public health authorities.
"If an outbreak were to occur, there's a limitation on how much they can target their response to that," he said.
"You've got New Brunswick and Ontario that really only start entering the data when kids enter school. It's extremely problematic, and it's a very, very large hole in Canada's vaccination framework."
Busby said "anti-vaxxers," or those opposed to vaccinating children, make up a "tiny" part of the population. The study focuses more on the need for a co-ordinated approach to educating new parents while making immunization as easy and accessible as possible.
"We believe that well designed vaccination policies could reach national targets while still accommodating choice."
Nurse-led programs may work better than physician-led ones, especially in areas grappling with doctor shortages, the study concludes.
Newfoundland and Labrador has a nurse-led system where information on a child is entered into a database at birth and a follow-up appointment is scheduled soon after.
A public health nurse offers vaccine information and requires written consent, or refusal, before the first immunization phase begins.
New parents are busy and complacency can affect whether children get all their shots, said economist Nicholas Chesterley, co-author of the study.
"Diseases they may never have seen ... because they grew up post-immunization, can still be very dangerous for their children."
Linking provincial recording systems into a national database is a big task fraught with technological issues, Chesterley said.
A national registry proposed in 2003 called the Panorama System is a step in the right direction but is not expected to fully track adults or immunizations as they're administered, the study says.
"Like immunization itself, it's something that's easy to put off," Chesterley said. "But it would be nice to have these defences in place before we need them, rather than afterward."
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