Measles may be first of ‘scourges of society’ to return: Brock prof
Adam MacNeil, associate professor of immunology, stresses the need for child vaccinations
As cases of measles increase across Canada, a Brock University immunologist fears it may not be the last vaccine-preventable pathogen to re-emerge if vaccination rates do not improve.
Adam MacNeil, associate professor of immunology, said any vaccine-preventable pathogen that has been “essentially eradicated” in Canada could come back if the use of vaccines that prevent them decreases enough.
“The only pathogen that humanity has successfully eradicated so far is smallpox. All of the others in Canada are considered vaccinepreventable diseases,” he said.
“We do a pretty good job of managing them with our established vaccine programs, but even within the measles, mumps and rubella (MMR) vaccine, we have seen in the past outbreaks of mumps when vaccine rates lapse. Rubella is something that has been detected in Canada in recent years.”
MacNeil said decreased vaccine rates leading to the increase in measles may be the result of missed medical appointments to get children caught up on the vaccinations they need, a feeling of complacency after once common infections have been all but eliminated decades ago, or opposition to vaccines that arose during the COVID pandemic.
Considering the severity many of those pathogens pose, MacNeil said “it’s not a joke.”
After vaccines that have become available during the past several decades have almost eliminated cases of many once common diseases, he said “we forget some of these scourges of society.”
“When you don’t have the circumstances in your community where you see your neighbour or your coworker or loved one actually infected by some of these things that are vaccine-preventable — and that’s why you don’t see them infected — we start to lose our collective memory of why it’s so important that we establish this community barrier to help keep everyone safe,” he said.
Public Health Agency of Canada (PHAC) reported last week 40 measles cases in Canada so far this year, including seven patients who were hospitalized due to the infection. Most of those cases were among unvaccinated children, and although some patients were exposed to measles while travelling internationally, others contracted the disease in Canada.
Measles infects more than 90 per cent of people exposed to the pathogen who have not been vaccinated against it or previously infected, and “can lead to rare but severe complications, including deafness and brain injury caused by inflammation of the brain, and can even be fatal,” PHAC said in a media release.
No recent measles cases have been reported in Niagara.
Some communities have recently struggled in the wake of the pandemic to get children up to date with mandatory vaccines required by the Immunization of School Pupils Act — such as in Waterloo, where 2,969 elementary students were suspended last week when their vaccination records were not updated.
Niagara Region Public Health has fared better than other jurisdictions.
Niagara’s vaccine-preventable disease team sent reminder notices last fall to the guardians of 12,856 students who were non-compliant with required vaccines, followed by suspension orders sent to 8,555 students in January.
But after clinics were held in many schools and public health offices across the region, as well as support provided to families needing to update their records, the number of students who were suspended on the March 19 deadline to be immunized was reduced to 1,284. By the end of that day, the number was reduced to 768 and by the end of the week it was down to 385 students, public health reported.
“As of today, we continue to work with around 150 students and families to help them achieve compliance,” Niagara Region Public Health said in an email.
While Niagara currently has a 95.13 per cent student vaccination compliance rate, it also includes students who have filed legal exemptions to receiving vaccinations.
While Niagara is close to the 95 per cent vaccination rate needed to prevent measles from spreading throughout the community, MacNeil said it won’t entirely eliminate the risk of transmission.
“Even in a large population that’s at 95 per cent, you could easily have a school that might be at half of that (vaccination rate),” MacNeil said, adding the disease could easily spread within that setting.
He said most adults have protection from the virus, after being vaccinated as children or developing immunity through past exposure. School environments with lapsed vaccination rates where measles have been spreading “are directly correlated with the attitudes of parents,” he added.
“Our current situation with vaccine hesitancy makes these things possible,” MacNeil said.