Skip to content

Pediatricians fear possible slide in vaccines may compromise herd immunity


TORONTO — Pediatricians are urging parents to maintain their children's vaccination schedule amid the COVID-19 scare, cautioning that even a slight dip in inoculation rates could jeopardize herd immunity for a host of other ailments.

Many children and young people are almost certainly behind on their shots as infection fears push some families to avoid medical facilities, says Dr. Shaun Morris, staff physician in infectious diseases at Toronto's SickKids Hospital.

At the same time, opportunities to inoculate have dwindled as family clinics scale down hours, switch to virtual care or shutter their offices completely. Meanwhile, school-based immunization clinics have been postponed indefinitely.

In provinces that require proof of vaccination to attend daycare and school, the closures remove one of the most powerful motivators parents have to keep their kids up-to-date, says a spokeswoman for the Canadian Paediatric Society.

Dr. Joan Robinson wonders if daycare and school closures could disrupt vaccine adherence even more than the vaccine hesitancy of families who question their safety.

"The most common reason Canadian children are not immunized is simply because the parents never got around to it," says Robinson, also a pediatric infectious diseases specialist in Edmonton.

"And that's not necessarily being critical of the parent. Many people have a very hectic kind of life — they maybe don't have a car, they're living in a not-great situation, so taking their 18-month-old for immunizations is pretty low down on the priority list."

It's only been about a month since most Canadians adopted strict physical distancing measures so Morris says we haven't yet seen whether vaccination rates will change significantly. But he's wary of the possibility, noting rates dipped in West Africa during the Ebola crisis, resulting in a spike of measles cases there.

"Myself as well as my research colleagues are in the process right now of thinking of how we can study this exact question to try to quantify it, to try to understand what reasons may be behind a decrease in immunization, and also importantly (what happens) downstream if it's related to an increase in vaccine-preventable diseases," says Morris.

Most physicians who have paused their work are referring patients to another doctor or pediatrician if needed, he says, but pandemics in general give rise to a whole host of factors that can derail routine care.

Ontario's school closures, for instance, have delayed school-based immunizations delivered by local public health units "until further notice," according to an email Tuesday from a health ministry spokeswoman.

Under normal circumstances, spring clinics would be underway right now to deliver the meningococcal conjugate, human papillomavirus (HPV) and hepatitis B vaccines to Grade 7 kids. Kids aged 14 to 16 are also required to get the three-in-one tetanus, diphtheria and pertussis (Tdap) vaccine under the province's Immunization of School Pupils Act.

The ministry said the closures themselves "help protect students until school-based immunizations resume" but there was no indication on when that might be. 

Like Ontario, New Brunswick requires proof of up-to-date vaccinations for kids at daycare and school unless they are exempted for medical reasons or parental objection, while British Columbia requires parents to provide immunization records for enrolled students.

Broadly speaking, Robinson says there's more leeway for older children to push their immunization schedule, so it's safe for tweens and teens to delay their shots until classes resume. She adds that public health would likely make accommodations if the closures extend for a long time.

It's a different story for the primary series of vaccines given to infants at two-, four-, six- and 12-months-old — those should "absolutely not" be delayed, says Robinson.

Nonetheless, Dr. David White, a family physician in Toronto, is aware of some parents who have postponed those early shots.

"The parents are in charge. You can't force them to come in," says White.

"If they're putting it off, we want to make sure that they have some idea of when they are going to come in. Because sometimes it's a perception issue, which we try and address."

White says there is very low COVID-19 infection risk to families seeking a vaccine at his office, which has converted most visits to virtual ones.

The door to his clinic is locked, forcing visitors to enter one at a time. The waiting room chairs have been removed to reduce the number of surfaces to clean. Where possible, visitors are encouraged to wait in their car until notified by phone to enter, and then they head directly to a closed-door examining room.

In addition, he asks that only one parent accompany their child, that adults and older children wear a mask and that everyone wash their hands upon arrival.

"Personally I think it's safer coming to our office than going shopping," says White.

Robinson stresses the importance of infant vaccines that prevent bacterial meningitis, which is more common and more serious in young children than in older children.

"It gets super-important to not delay those immunizations, no matter what," says Robinson, who works at Stollery Children's Hospital.

Even the 18-month-old shot, which is meant to boost immunity to vaccines the child already has, should be given on time if possible, she advises.

"I wouldn't be horrified if people wanted to put it off for a month or two. However, I think we need to realize that this pandemic situation could go on for a long, long period of time."

The preschool immunization should ideally be given at age four but can be delayed until age 6, "if parents really want to," she adds.

"If it was my child I would get it right on time because I don't want them to be getting whooping cough, which is one of the most important things it prevents."

Vaccinating children does more than protect the child — it can also protect adults who can be infected by children, adds Morris.

He points to a vaccine given to babies at two-, four- and 12-months that protects them against streptococcus pneumoniae, which is the bacteria that causes pneumonia, bloodstream infections and brain infections.

"There's an indirect benefit to adults by immunizing children," he says.

This report by The Canadian Press was first published April 22, 2020.

Cassandra Szklarski, The Canadian Press

Looking for Ontario News? viewed on a mobile phone

Check out Village Report - the news that matters most to Canada, updated throughout the day.  Or, subscribe to Village Report's free daily newsletter: a compilation of the news you need to know, sent to your inbox at 6AM.