National picture of children’s vaccination rates hard to get

[PHOTO COURTESY: CBC News]

Kids across the country are back to school after the holiday break but hundreds in Ottawa are still at home. That’s because the city is enforcing provincial restrictions requiring Ontario public school to be up-to-date on their vaccine schedule, and has suspended those who are not and don’t have valid exemptions.

About 5,000 suspension letters were sent for children in public schools in Ottawa on Dec. 15 because of their out-of-date vaccination records. Fifty thousand students had incomplete vaccination records in the city as recently as October. And when school started this week, about 1,800 students were suspended as a result.

The suspensions are lifted when a student provides either a valid exemption or proof of current vaccinations. As of Monday, 82 per cent of those students had provided the proof required to return to classes.

But documentation of vaccinations varies across the country, making it hard to get a good national picture of immunization rates for children.

“Those are not well tracked,” Dr. Gerald Evans, an infectious disease expert at Queen’s University, tells Yahoo Canada News.

The routine vaccination schedule varies between Canada’s 13 provinces and territories, as do the requirements for vaccination to attend public school. Only Ontario and New Brunswick legislate that children must be up to date on vaccines in order to attend public school. In all other provinces and the three territories, the regulations and policies around vaccine reporting and vaccine tracking — as well as legislation related to disease outbreaks —varies.

What that means is that it’s hard to get a true picture of vaccination rates for children across the country. The data Canada supplies to the World Health Organization puts the country’s vaccination rate for measles at 95 per cent, for example, but a recent C.D. Howe report found that only 66 per cent of children in Nova Scotia are fully immunized against the disease. And a 2013 report by UNICEF put Canada’s rate for measles and other contagious diseases as 84 per cent — well below the 95-per-cent national target and near the bottom of a list of 30 developed nations.

The provincial overview

The differences in those numbers illustrate how hard it is to say exactly what provincial vaccination rates look like. And beyond that, even if we knew how many Canadian children weren’t fully immunized, most provinces can’t legally compel parents to get them up to date.

In Ontario, the Immunization of School Pupils Act requires that in order to attend school, students in Ontario have proof of immunization against tetanus, diphtheria, polio, mumps, measles, rubella, meningococcal disease, pertussis and varicella.

Parents and guardians in Ontario who don’t want their children immunized are able to file an exemption for religious, philosophical or medical reasons. Children with exemptions are required to stay home from school in the case of an outbreak of a vaccine-preventable disease.

And like Ontario, New Brunswick mandates that children be up to date on their vaccinations in order to attend school. Manitoba once had a vaccine requirement for measles for children attending public school, but vaccinations are now voluntary according to the provincial government.

The other provinces and the territories have varying legal and policy positions around vaccinations for schoolchildren. For example, Alberta has no legislation mandating that proof of vaccination be provided in order for children to attend public school. However, Alberta’s Public Health Act requires that children who are not immune to measles (haven’t been vaccinated) stay home from school during an outbreak.

And even in those provinces that mandate vaccinations for schoolchildren, enforcement varies considerably. Only Ottawa and Toronto have enforced suspensions for students who haven’t provided vaccination records after multiple warnings, for example.

“From a Canadian Medical Association point of view, we certainly encourage provinces and territories to require proof that children have received their vaccinations when they register for school,” Dr. Cindy Forbes, a family physician and Canadian Medical Association president, tells Yahoo Canada News.

But the decision falls to the individual jurisdictions because health care is under provincial administration in Canada. This also means that what we know about vaccination rates varies considerably across the country.

“Most provinces don’t have vaccine registries that would be current or up to date,” Dr. Forbes says. And there is no national vaccine registry.

Setting up a national registry would provide a countrywide picture of vaccination rates, making it easier for public health agencies to promote vaccinations as necessary. It would also be of use in case of an outbreak, Dr. Forbes says, because it would make it easier to see which parts of the nation could be particularly at risk.

“That would give us an idea of if it’s a huge problem or a medium problem or a small problem,” Dr. Evans says.

But setting up those registries involves a host of logistical issues. For example, in some provinces mechanisms are involved in vaccinating children, Dr. Forbes says. Children may receive their earliest vaccines through their family physician, and later ones through the public health system once in school. Vaccine records are not necessarily automatically passed on from one’s doctor to the school district, or from province to province when a family moves.

“It actually highlights the issue of having provincial, and possibly even national vaccine registries,” Dr. Forbes says.

Getting an exemption

Public opinion across the country seems to fall firmly in favour of routine childhood vaccinations. Two-thirds of Canadians believe that children should be required to be up-to-date on vaccinations in order to attend daycare, according to an Angus Reid survey done last year.

But the same survey highlighted generational and regional differences that show the philosophical divide that exists in some communities, and these divides make it more difficult to enact a national strategy on vaccine communication, Joshua Greenberg, a Carleton professor and expert in public health communication, tells Yahoo Canada News.

Those differences in regional attitudes around things like parental choice make it difficult to devise a national vaccine-promotion strategy, Greenberg says.

The Angus Reid survey pointed to some of those differences. Older Canadians with grown children are much more likely to support mandatory vaccination than those with young children, at 71 per cent versus 56 per cent. Parents in Ontario and Alberta are more strongly in favour of mandatory vaccination for schoolchildren versus voluntary (71 per cent versus 18 per cent), while those in Quebec are nearly evenly split (45 per cent versus 43 per cent).

And while 88 per cent of Canadians agree that vaccination is effective for disease prevention, and 86 per cent say it benefits the wider community, younger people are again more likely to be skeptical of the pros of vaccination than their older counterparts. Forty-four per cent of Canadians aged 18-34 said the science on vaccinations isn’t clear, versus 34 per cent of those older than 55.

Along with regional and generational differences in attitudes about vaccinations, actual vaccination rates appear to vary nationally as well. Newfoundland and Labrador has the highest vaccination rates in the country at 95 per cent, according to the C.D. Howe Institute report released in March 2015. The same report found that vaccination rates for children across Canada vary from 70 per cent to 95 per cent, but that most provinces fell below national targets.

The rates can also vary considerably from city to city, or even from school to school within one municipality. In Toronto, for example, 2012 Toronto Public Health data showed that rates for MMR (measles, mumps and rubella) vaccinations were just 43.75 per cent at Alpha Alternative School in Toronto, and several other schools had rates below national targets.

But all over the country, there have been declines in overall vaccination rates.

“We know that the rates are falling,” Dr. Forbes says. “All of the Canadian provinces are below national targets for vaccine coverage for preventable childhood diseases.”

The actual number of people who are strongly opposed to any vaccines is actually quite small, Greenberg says. Some estimates put it at about 2 per cent. But there is a larger group that is skeptical or unsure of vaccines and therefore put off getting them, spread them out or miss doses, and this also has public health consequences.

Why herd immunity matters

Those drops in vaccination rates may seem small, and the large majority of students are vaccinated in nearly every school in the country. But maintaining high rates of vaccination is important for ensuring herd immunity.

Because contagious diseases spread person to person, it is difficult for them to spread far when nearly everyone in a population is immune to them because they have been vaccinated. This protects those in the group who are not immune for reasons like age, a vaccine allergy or a compromised immune system that prevents them from receiving vaccination. This is what experts refer to when they discuss herd immunity.

However, as the number of people in a population with immunity drops, it becomes easier for a contagious disease to spread. Vaccination rates for herd immunity vary by disease. For a highly contagious disease like measles, for example, a vaccination rate of 90 to 95 per cent is required.

That’s why outbreaks of diseases like measles and pertussis (whooping cough) across the country in recent years worried health experts who were concerned about dropping vaccination rates.

Whooping cough cases jumped to 4,540 in 2012, according to the Public Health Agency of Canada, up from 695 the previous year. And national measles cases numbered 752 in 2011 because of an outbreak.

But the reasons for missed vaccines vary considerably, from outright objection to vaccination to hesitancy about it or logistical issues.

“Sometimes immunizations just get overlooked, for other reasons,” Dr. Forbes says.

Some parents may never vaccinate their children, against any illness; others may have forgotten a shot or two unintentionally, or delayed the required vaccinations because of worries about the number of shots.

“That’s why mandatory reporting can be a really helpful measure,” Dr. Forbes says, “because it allows us to take stock and stop.”

Mandatory reporting in the various provinces and territories can help catch most of those who have missed vaccines for reasons that aren’t due to objections to the shots, she says, and provides an opportunity to communicate with the rest about the importance of getting up to date.