Toronto public health officials say they are worried parents are delaying vaccinating their children against illnesses such as polio, measles and whooping cough because of unfounded concerns about links to autism.
In a new report, they say this "vaccine hesitancy" led to an outbreak of measles among five unvaccinated children at the same Toronto day nursery in February 2013.
Public health data shows Toronto's rate of mandatory school vaccinations was 90 per cent for 2011/2012. But there are still pockets of unvaccinated children in the city.
Barbara Yaffe, associate medical officer of health and director of communicable disease control for Toronto Public Health, says the success of vaccination programs means the effects of these diseases are often far from people's minds. But in today's globalized world, the risk is still very real.
"In the 40s and 50s people were worried because they saw people paralyzed and in lung machines. They were happy to get vaccines for themselves and their children. But as these diseases are starting to become rare, people are starting to think less about the diseases and more about the vaccines."
Dr. Yaffe said parents are particularly concerned about links between vaccines and autism but she says the evidence does not support this. The most common side effect of the measles vaccine is "a sore arm," she said.
She reported that in February 2013, there was an outbreak of measles in Toronto. It started with two siblings whose parents had decided to delay getting the vaccine because they were worried about potential links to autism. Three more unvaccinated kids in the same nursery also came down with measles.
All of the infected children have now recovered, but Dr. Yaffe said it could have been worse.
"People think measles is no big deal, but one in 15 measles cases have serious complications," she said. They can include pneumonia, brain swelling and death.
The report says it's critical Canadians continue to get their immunizations as even a small drop in vaccination rates could lead to resurgence in diseases.
"In the UK, there's quite a serious outbreak. The vaccination rate dropped by about 10 per cent and a lot of the kids in that cohort missed out on their vaccination," said Dr. Yaffe.
The Guardian is reporting that there are now over 1,000 cases of measles in Swansea, Wales, with 50,000 people across the area unvaccinated and unprotected. A 25-year-old man who had measles has died, but it's unclear whether measles was the cause of death.
Dr. Yaffe attributed the drop in UK vaccinations to one 1998 article printed in a medical journal that linked autism to the measles, mumps and rubella vaccine. She said the article was later retracted and the doctor who wrote it lost his licence. It's the only article she's aware of that links autism to the vaccine but she said the "misinformation has remained on the internet."
According to one study mentioned in the report, in 2011, 63 per cent of Canadian parents used internet searches such as Google to find information on vaccine safety. Only 54 per cent went to a doctor with their questions. The study found that parents with annual incomes greater than $120,000 were more likely to use Google searches for information than those with lower incomes.
The report was passed by the Board of Health on Monday. It also contains recommendations to the Ontario government to streamline systems for immunization records and improve communication with the public.
Another report released recently by Unicef said only 84 per cent of Canadian children received the appropriate dose of the measles, polio and diphtheria, whooping cough and tetanus vaccine. At the time, Canadian public health officials expressed doubt about the data, saying if the rate was really so low there would be more outbreaks.