Alberta immunization rates lagging
Missed targets increase risk of outbreaks, experts warn
As diseases such as measles and mumps remain threats to public health, Alberta continues to fall short of hitting targets for childhood immunization coverage that have been in place since the last century.
According to government data for 2016, the actual numbers for immunization of two-year-olds who had received the full diphtheria, tetanus, pertussis, polio and Hib immunization was 77 per cent, while 87.9 per cent had received their measles, mumps and rubella shots.
However, the targets for coverage, based on national standards, are 97 per cent and 98 per cent respectively.
That level of immunization has been the goal since at least 1999, but actual vaccination rates have held steady near the most recent numbers over that time period.
With National Immunization Awareness Week now underway, Dr. Karen Grimsrud, chief medical officer of health for Alberta, said the ongoing gap is a cause for concern.
“For measles, mumps and rubella . . . we know at that level of immunization we’re going to get outbreaks once in a while,” Grimsrud said in a recent interview.
“You have to have a high enough immunization rate for something like measles in order to provide enough protection that even those who aren’t protected won’t necessarily get measles. If we had 98 per cent coverage, we wouldn’t get any sort of spread of measles. We might have a case coming into the country but it wouldn’t spread. But if you have 88 per cent coverage, you will get some secondary cases.”
Earlier this year, Alberta Health Services declared mumps outbreaks in the south and Edmonton zones.
Just two weeks ago, AHS warned that shoppers in a northwest Calgary drugstore had potentially been exposed to measles, which can be deadly.
Grimsrud declined to criticize past efforts to address the immunization issue, but expressed confidence that a new initiative will pay off for the province.
Last fall, the NDP government passed legislation that allows school records to be matched against Alberta Health’s vaccination data to allow school officials to access the files quickly in the case of a serious outbreak.
The law, which came into force in December, also means that parents whose children have not been immunized will be contacted by health officials, who will provide information on the benefits of immunization.
The government stopped short of following the lead of New Brunswick and Ontario, which require students to be vaccinated to attend school. The Edmonton Catholic school board last week called on the government to mandate vaccinations for students.
But Grimsrud thinks the new Alberta law — which encourages “informed decision-making” — will have a greater effect than a heavy-handed mandatory system that still allows for exceptions.
“It’s something we haven’t tried before,” she said.
“My thinking is we will see a substantial increase in our childhood or school-age immunization rates as a result of that, because it’s a pretty big step forward.”
In 2016, the number of children aged seven who had received their second dose of the measles, mumps and rubella immunization stood at 80 per cent.
Liberal Leader David Swann, who in 2015 proposed mandatory immunization for students, said Friday that the government’s initiative should be given a chance over the next few years to see whether it affects rates before considering mandatory vaccinations.
Swann, a physician, said there are a couple of factors depressing immunization numbers.
The anti-vaccination movement, often propelled by celebrities, that makes unsubstantiated claims about dangers of vaccines, is a serious concern, he said.
“The good news is (the rate) hasn’t gone down,” said Swann.
“But … it’s disappointing we can’t get it up to where it should be.”
Swann said access is also an issue that affects immunization levels.
The government’s database shows the highest level of immunization among AHS’s five zones for diphtheria, tetanus, pertussis, polio and Hib immunization was 81.9 per cent in the Calgary zone, while the south zone was the lowest at 68.2 per cent. The two zones were also the highest and lowest for measles, mumps and rubella coverage, at 89.9 per cent in Calgary and 82.1 per cent in the south.
Ian Culbert, executive director of the Canadian Public Health Association, said meeting immunization targets is a problem across Canada.
Beyond issues over access and opposition to vaccinations, immunization rates have slipped due to the sheer success of immunization in reducing disease, leading parents to believe shots aren’t necessary for themselves or their children, he said.