ANTI-VACCINE THREATCombatting the Measles Threat Means Examining the Reasons for Declining Vaccination Rates
Measles was supposedly eradicated in Canada more than a quarter century ago. But today, measles is surging. The cause of this resurgence is declining vaccination rates.
Measles was supposedly eradicated in Canada more than a quarter century ago. But today, measles is surging.
Public Health Ontario recently announced that there have been 173 cases in the province in the past two weeks and 350 cases since autumn 2024. Many cases have required hospitalization. Last year, a child died.
The cause of this resurgence is declining vaccination rates.
Measles is extremely infectious. One person with the measles is likely to infect nine out of 10 of their unvaccinated close contacts. To prevent its spread, we need 95 per cent of the population to be vaccinated.
Anti-Vaccine Sentiments
Our research examines why parents have hesitated or refused to vaccinate their children. Anti-vaccine sentiment is often linked to a now thoroughly discredited 1998 study that suggested a link between the MMR (measles, mumps and rubella) vaccine and autism.
But our research on the anti-vaccine movement in Canada from the 1970s to the early 2000s suggests that parents’ concerns about vaccines started much earlier than that study, and that parents worry about far more than autism.
To address anti-vaccine sentiment, we need to listen to parents’ concerns and make it easy for them to get their children vaccinated. We also need to persuade them of the benefits of vaccination, not just for their own children, but for their family members, friends and fellow citizens.
The anti-vaccine literature is not anti-science. It is filled with statistics and references to scientific studies, although the facts are often wrong. Parents who read this literature need more than the simple reassurance of experts that vaccines are safe and effective. They need to be shown evidence and have confidence that their concerns are being taken seriously.
One argument that appeared frequently in the anti-vaccine literature is that rates of infectious disease had fallen before the introduction of vaccines.
While mortality from infectious diseases declined well before vaccination, vaccines played a vital role in further diminishing the toll of infectious disease. Diphtheria is largely unknown today, but before the introduction of widespread vaccination in the years between the First and Second World Wars, it killed hundreds of Canadian children every year.
Another common argument was that vaccines are ineffective. This argument was often used with respect to the measles vaccine. Because some people are inadequately vaccinated (receiving only one shot for example, instead of two), and because the vaccine is not perfect, there will be some cases of measles even in vaccinated people. Fortunately, these people tend to have milder cases.
