June – Keeping Measles At Bay

Written by Communications, June 12, 2019

Measles has made a comeback in Ontario. As of May 23, there have been 11 laboratory confirmed cases, all of them related to travel outside of the country, where measles outbreaks are occurring. Why are we so concerned about this disease? The World Health Organization estimates that in 2017, 110,000 children died from measles, most of them under the age of five years. The virus is highly contagious, spreading through the air. It can cause blindness, hearing loss, pneumonia, severe diarrhea and dehydration, and swelling of the brain called encephalitis that can be fatal.

We don’t see measles-related deaths in Canada anymore because we have a very effective vaccine, now given in two doses, one at 12 months of age and the other just before starting school, between the ages of four and six years. Two doses are considered to be between 95 to 100% effective in preventing the disease.

Here in Peterborough, we have been measles-free since 2008. Recently we have had a number of Peterborough residents exposed to measles elsewhere in the province – so far, none have become ill. Peterborough Public Health does contact each person with a known exposure as part of our follow-up. If you grew up in Ontario and were born before 1970, you are probably immune as the disease was circulating widely then. And fortunately, most of our school-aged children are protected. According to our records, 88% of Peterborough’s students have two doses on file. And 98% of students are up to date, according to age, as there are four, five and six year olds who may not have had their second dose yet. These numbers are reassuring.

Ontario requires all students to be fully immunized in order to attend school and public health is charged with enforcing this legislation. Until Ontario has a fully functioning immunization registry which will allow doctors and nurses to enter data directly each time they administer a vaccine, parents need to call us with the immunization history, or enter it directly online by visiting www.peterboroughpublichealth.ca and clicking on “Update Your Child’s Record” to find a link to the portal.

Anti-vaccination messaging available on social media and the internet is raising concerns that some parents may be choosing not to immunize their children based on an unfounded or exaggerated fear that may not be supported by what the evidence actually shows. As part of our provincial vaccine safety surveillance, Public Health Ontario reports annually on the millions of doses of vaccines administered every year. In 2017, of the 8.5 million doses of publicly funded vaccines administered in Ontario, there were only 696 adverse events reported. Most were mild. Serious adverse events were very rare, occurring at a rate of 3 per million doses.  Vaccines are safe, yet here in Peterborough, almost 3% of parents are choosing not to immunize their children.

To counter the harm of misinformation, the University of Toronto recently announced the creation of a Centre for Vaccine Preventable Diseases, to be led by Dr. Natasha Crowcroft, chief science officer at Public Health Ontario. As the first academic centre in Canada to focus on building the public’s confidence in immunization, Dr. Crowcroft has shared her hope that more parents will understand the value and role of immunizations in boosting immune systems and protecting their children better. She worries that vaccine hesitancy of parents is a growing threat to the public’s safety. Only a road trip away, in New York City, a measles outbreak rages on, with 550 confirmed cases as of May 29. Officials have had to resort to issuing fines of $1000 to parents of unvaccinated children in order to bring the outbreak under control.

Each dollar spent on the measles-mumps-rubella vaccine saves $16 in averted health care costs because children will not get sick or die. I can still recall what measles looks like because I have seen it – thirty years ago, in my own daughter. But in my lifetime as a physician, we have almost made measles history, thanks to immunization. We now have vaccines that prevent cancer, like those against HPV and Hepatitis B. Let’s hope as many inroads against vaccine hesitancy can made as we’ve been able to make against the diseases themselves.