Her daughter, Annalyn, was born almost three months before her expected due date and Annalyn's weakened immune system leaves her vulnerable.

"I think my worry, going home, would be that there's lots of different bugs and different things out in the community and for Annalyn to catch one of those things," says Booy.

It's children like Annalyn that have Julie Bettinger stressing the importance of "herd immunity" when it comes to communicable diseases.

"Vaccines protect not only you, the individual, but everyone around you: your family, your friends, kids at your children's school. If you care about your community, you should be vaccinated," says Bettinger, an associate professor of pediatrics for UBC and BC Children's Hospital Vaccine Evaluation Center.

There are many people who simply can't be vaccinated and depend on those around them to stop the spread of communicable diseases. Children typically aren't vaccinated for things like measles, mumps, rubella or chickenpox until they're at least one year old.

"It's the younger children, under three months of age, who get the worst disease. And also children who have cancer and who've had transplants and are on medications, meaning they can't get some vaccines," says Dr. Manish Sadarangani, a pediatric infectious diseases physician and Director of BC Children's Hospital's Vaccine Evaluation Center. 

Protect the vulnerable

Shannon Westerlund's son, Andrew, was diagnosed with a heart condition when he was 12. He received a heart transplant and, 18 months later, was diagnosed with cancer. Protecting him from illness is always a worry.

"The common cold can cause an issue for him," says Westerlund. "He gets sick for two weeks with just a regular cold so when it comes to things like mumps, measles and chicken pox, those are literally life-threatening for him."

Sadarangani has seen children with compromised immune systems catch preventable diseases like chickenpox.

"In these cases, it's really sad because it's not just the case of a few itchy spots on their skin," he says. "The virus spread to their lungs, to their liver, and to their brain and made them very, very sick. One child unfortunately died from chicken pox."

Help prevent serious disease

Sadarangani says some people mistakenly take communicable or infectious diseases lightly. Measles is highly contagious and at least 95 per cent of the population needs to be immunized to develop herd immunity.

"Measles can be a really nasty infection. Most people view it as just another one of these infections that can cause a fever, a rash, and a bit of a cough and a cold. But, it's actually much more severe than that," he says. "It's very frequent for children to get secondary complications on top of the actual measles virus infection. The commonest are ear infections and pneumonia. You can also get bad gut infections and, in some cases, it can cause complications in the brain."

Immunization is very effective at preventing measles infection. Two doses of the measles, mumps and rubella (MMR) vaccine is 99 per cent effective in protecting you and your family. The MMR vaccine is considered safe, even for people who have severe egg allergies.

He knows there are parents and caregivers of children who have questions and can be hesitant about getting their children vaccinated.

"I think their reasons are complex and different from one family to another," he says. "They should seek out answers to their questions from reliable sources of information, which is usually their health care provider or the public health immunizers."

Vaccine safety

Bettinger stresses that vaccines are safe.

"Our vaccines are continuously monitored to ensure that they are safe," she says. "And study after study shows that they are safe. Not only that, but even after we start using a vaccine, we keep monitoring it to make sure that they stay safe."

Booy, who is heading home with her daughter, Annalyn, is hoping her community understands the importance of stamping out communicable diseases.

"I would strongly encourage parents to immunize their kids, not just for their own kid, to avoid getting sick or potentially being hospitalized, but for kids like Annalyn."

How to get vaccinated

It is important to ensure your own, and your family's vaccinations are fully up to date. Families can find a convenient vaccination clinic location close to home on the Immunize BC website: https://immunizebc.ca/finder

BC Children's Family Immunization Clinic provides all publicly-funded immunizations at no cost to patients at BC Children's and BC Women's and their friends and family visiting the hospital. For information, visit: http://www.bcchildrens.ca/our-services/clinics/family-immunization

B.C.'s measles immunization catch-up program

Following a measles outbreak in Vancouver in early 2019, the Ministry of Health launched a measles immunization catch-up program in spring 2019 to encourage parents of school-aged children to immunize their children. This launch was followed by an announcement of mandatory reporting of vaccinations at B.C. schools, beginning in fall 2019. Families can find more information here: https://www.healthlinkbc.ca/vaccination-status-reporting.

Dr. David Scheifele, who recently retired as director of the Vaccine Evaluation Center at BC Children’s Hospital, explains why parents should fear measles and not the vaccine in a recent article in The Conversation.