By Kathleen Couillard

Vanessa Crevier Bélanger’s daughter, Rosaly-Ann, was born last January. “I’m not really in favour of vaccination, but my husband is,” says Vanessa. Rosaly-Ann was given her scheduled vaccines at 2 months of age, but her mom is hesitant about the next ones.

There are different types of vaccine hesitancy. “Some parents will let their child get one vaccine but refuse another,” says Laurence Monnais, a historian who specializes in the history of health and medicine. “Others may delay their child’s vaccination schedule.” There are also parents who say they’re vaccine-hesitant, but let their child get vaccinated anyway.

It’s therefore important to distinguish between vaccine hesitancy and the anti-vaccine movement, which rejects all vaccines and often aims to convince other people to refuse vaccines as well. “Anti-vaxxers make up a very small minority of people,” Monnais states. “In fact, they make up less than 2 percent of the population.”

According to Monnais, vaccine hesitancy is nothing new. “There are examples of vaccine hesitancy in newspapers from the 1960s to the 1980s. Parents would bring up their concerns in letters to the editor,” she says.

Are there more reluctant parents than before?

Although there’s a lot of talk about parents being reluctant to vaccinate their children, there are fewer of them than before. “In 2019, 23 percent of parents said they were hesitant, compared to 30 percent in 2016,” says Marilou Kiely, a scientific advisor at the Institut national de santé publique du Québec (INSPQ).

Even though some parents are hesitant, that doesn’t seem to affect the percentage of children who get vaccinated over the years, a statistic known as vaccination coverage. “The latest study, which was conducted in 2019, even shows an increase in vaccination coverage for all vaccines in the regular immunization program,” Kiely states. In addition, only 1 percent of children haven’t received a single vaccine, and this percentage has remained steady over the years.

Studies show that parents who have a negative opinion of vaccines or who’ve been hesitant to vaccinate their child in the past are more likely to refuse certain vaccines or delay vaccination. According to experts, in order to prevent their fears from evolving into a blatant refusal to vaccinate their children, we need to understand why parents become hesitant in the first place. This is important because vaccination rates must remain high to ensure the population continues to be well protected. For example, in the case of measles, experts estimate that 95 percent of children need to be vaccinated to prevent outbreaks.

In addition, the COVID-19 pandemic may have compounded parents’ vaccine hesitancy. Marie-Ève Brouillette, a perinatal nurse, has noticed that parents have been asking more questions lately. “Routine vaccines have become a hot topic all of a sudden,” she says. “This has triggered a period of reflection.”

Causes of vaccine hesitancy

According to Dr. Arnaud Gagneur, a physician and researcher at the Université de Sherbrooke, the vast amount of information circulating about vaccines may explain some of the hesitancy among parents. There’s also a lot of false and contradictory information out there. “Many parents know very little about diseases and vaccines, so they’re in the dark about a few things,” he says. Going through a pandemic only makes things worse. “It leads to anxiety and even more hesitancy,” Dr. Gagneur adds. He believes that if the COVID-19 vaccination campaign is successful and allows us to resume our normal lives, people’s confidence in vaccines could improve.

In addition, some people are afraid of things they don’t understand, Dr. Gagneur notes. Like Vanessa Crevier Bélanger, many parents have a lot of questions about vaccines. “What are they, exactly? How are they made? Even when these things are explained to us, the answers aren’t always clear,” she laments. In the past, there was more information about vaccinating children,” Monnais points out. “There were advertisements, and people knew about vaccines and how important they are for the collective.”

Finally, some people think that we have too many vaccines and question whether they’re all truly necessary. For example, they wonder why they need to vaccinate their children against gastroenteritis or chickenpox, since these diseases don’t seem dangerous to them. “Certain diseases have been trivialized,” states Dr. Gagneur.

Experts believe that vaccines may in fact be victims of their own success. Vaccines are so effective that the diseases they serve to prevent are now uncommon. “For instance, we don’t remember the severe complications associated with measles,” says Dr. Gagneur. “But if a vaccine was developed, it’s because the risks associated with catching the disease are significant.”

Listen, don’t judge

“Vaccine-hesitant parents frequently tell me they feel judged, which just makes them more unsure,” says Dr. Gagneur. Brouillette has noticed the same thing. “A lot of parents tell me they lied to their health care provider because they feared being judged,” she notes. “That’s a bit dangerous because they may turn to other sources of information, which aren’t always reliable.”

But Vanessa doesn’t want anyone to try to convince her. She wants someone to take the time to explain things to her. “I want to make informed choices,” she says. “This is my child. If I decide to vaccinate my daughter, I want to know what the consequences will be.” Monnais maintains that as far as she’s concerned, vaccine hesitancy is legitimate. “When you’re a parent, it’s essential to question things to make sure you’re taking the best possible care of your child,” she says.

For this reason, Dr. Gagneur has developed a program that gives all parents the option to have an open and non-judgmental discussion about vaccination with an immunization counsellor at the hospital, after delivery. This program, also known as EMMIE, aims to help parents make a decision. “Our immunization counsellors are available to answer their questions and give them the information they need,” Dr. Gagneur explains.

Parents who are reluctant to have their child vaccinated are often hesitant because they have questions about the safety, necessity, and effectiveness of vaccines. We asked experts to address some common concerns.

Why do vaccines contain chemicals? Are they dangerous?

“Generally speaking, the chemicals in vaccines are necessary preservatives,” says Marie-Ève Brouillette, a perinatal nurse. Other ingredients, called adjuvants, are used to make vaccines more effective. Adjuvants cause inflammation, which serves to activate our immune system. Studies have shown that if there is no adjuvant, the body’s immune response isn’t as strong, says Dr. Arnaud Gagneur, a physician and researcher at the Université de Sherbrooke.

“The ingredients list on its own can be scary,” says Brouillette, “but you have to consider the quantities.” Certain vaccine ingredients are present in much lower concentrations than what’s found in household cleaning products, or even in food. For example, many people are concerned about the aluminum in vaccines. And yet, many foods contain trace amounts of aluminum, including fruits, vegetables, flour, cereal, nuts, dairy products, infant formula, and honey.

How do vaccines work?

Vaccines activate the immune system so the body can defend itself against certain viruses and bacteria. The immune system reacts to molecules called antigens that are found on the surface of viruses and bacteria. When your body encounters an antigen for the first time, explains Dr. Gagneur, it starts to produce antibodies that help fight the disease. This way, if a person encounters the same virus or bacteria again later in life, their antibodies will prevent them from getting sick. “The principle of vaccination is to inject only the antigens, not the parts that could cause the disease,” says Dr. Gagneur. This is sufficient to allow the body to defend itself.

Messenger RNA vaccines, however, such as the COVID-19 vaccines developed by Pfizer and Moderna, are slightly different. Instead of containing antigens, they hold the recipe that allows the body to manufacture its own antigens to trigger an immune response.

While most vaccines contain only parts of inactive bacteria or viruses, there are a few exceptions. Some contain live, weakened bacteria or viruses that have been treated in a laboratory to prevent them from causing disease. This is true of the measles and chickenpox vaccines, for example. Because these vaccines are live, they occasionally cause mild symptoms. For example, a child may get a few spots of chickenpox after receiving the vaccine. However, they won’t be contagious, and they’ll be protected from serious chickenpox complications.

Why vaccinate children against COVID-19 when they’re largely unaffected by the disease?

Children aged 5 and older can’t get the COVID-19 vaccine yet, but this could change by the end of 2021.

According to experts, to achieve herd immunity (i.e., for everyone to be protected against COVID-19), at least 80 percent of the population must be vaccinated. It’s difficult to meet that threshold without vaccinating children, who represent 20 percent of the population.

Even if children don’t develop severe symptoms, they can still transmit the virus. The more the virus is transmitted, the more likely it is to make “mistakes” when replicating itself. These mistakes are the reason why variants arise. Ultimately, the sooner we vaccinate as many people as possible, including children, the fewer new variants we will see.

In addition, kids who contract COVID-19 can, in some cases, develop long COVID or multisystem inflammatory syndrome (link in French).

Why do people need to be vaccinated against diseases that have almost disappeared?

“When we no longer feel threatened by a certain disease, that’s an indication that we’ve done our job with vaccines because large outbreaks have stopped occurring,” says Brouillette. “That said, these diseases are still a threat. That’s why we have to keep vaccinating.” Many diseases that have disappeared in Quebec are still common elsewhere in the world. “The recent measles outbreaks, for example, happened because people who hadn’t been vaccinated caught the disease while travelling,” says Marilou Kiely, a scientific advisor at the INSPQ.

We can only stop vaccinating against a disease once it has been completely eradicated from the planet. This is the case of the virus responsible for smallpox, for instance.

Is a 2-month-old baby too young to receive a vaccine?

“This question is understandable since parents typically think of their baby as being very fragile,” says Brouillette. “However, it’s precisely because babies are fragile that they need to be vaccinated. We have to protect them from diseases that could cause serious harm.”

A baby’s immune system is functional, but not fully mature. It isn’t capable of recognizing certain bacteria, says Dr. Gagneur. “That’s why infants under 2 months are vulnerable to a number of serious infections, like meningitis,” he says. Fortunately, there are vaccines that allow a baby’s immune system to react properly to these bacteria. Delaying vaccination therefore puts babies at greater risk.

Why do I need to have my child vaccinated if most people have already received the vaccine?

The more people are vaccinated, the less likely the disease is to spread. This reduces the risk of infection. “When you vaccinate your child, you’re not just protecting them, you’re also protecting other people’s kids,” adds historian Laurence Monnais, who specializes in the history of health and medicine. “When they’re protected, we’re protected too.” Furthermore, having your child vaccinated helps protect more vulnerable segments of the population who either can’t get vaccinated or are likely not to respond as well to vaccines.

Why isn’t the vaccination schedule more spaced out?

“Parents can choose whether or not to vaccinate their child and whether to follow the applicable vaccination schedule,” says Brouillette. “But this can have an effect on the level of protection their child will benefit from.”

As Kiely notes, the vaccination schedule was designed in accordance with the risk associated with certain diseases and the strength of a child’s immune system: “Early doses are effective in preventing complications. However, to ensure adequate protection, several doses are required before the age of 2. Delaying vaccination makes a child more vulnerable. That’s why it’s best to follow the schedule, which was developed by experts.”

Source:Naître et grandir magazine, September–October 2021 Research and copywriting: Kathleen Couillard Scientific review: Ève Dubé, medical anthropologist at the INSPQ; and Dr. Caroline Quach, pediatrician and microbiologist/infectious disease specialist at CHU Sainte-Justine and full professor at the Université de Montréal

Photos (in order): GettyImages/Geber86, GettyImages/Rawpixel, GettyImages/Solstock, and GettyImages/Fluxfactory