Back to School: Important Immunizations

It’s back to school time – but before kids return to the classroom, it’s important to ensure they’re up-to-date on vaccines to keep them, and others, safe and healthy.

The World Health Organization and United Nations Children’s Fund (UNICEF) recently sounded the alarm, announcing that more than 25 million children worldwide have fallen behind on routine, life-saving vaccines – the largest sustained decline in approximately 30 years.

“While a pandemic hangover was expected last year as a result of COVID-19 disruptions and lockdowns, what we are seeing now is a continued decline,” said Catherine Russell, UNICEF Executive Director. “COVID-19 is not an excuse. We need immunization catch-ups for the missing millions or we will inevitably witness more outbreaks, more sick children and greater pressure on already strained health systems.” 

Vaccination rates in decline across Canada

In Canada, vaccination rates have declined by several percentage points in some provinces. In Alberta, coverage dropped from 84.5 percent in 2020 to 77.7 percent in 2021 for the MMR vaccine, which immunizes against measles, mumps and rubella.  

In Saskatchewan, 76.4 percent of two year olds were immunized against pertussis in June 2021, compared to 73.4 percent in June of 2022.

A similar situation is occurring in Ontario. When comparing the 2019-20 school year against the 2020-21 school year, immunization rates dropped for hepatitis B (25 percent to 16.8 percent), HPV (5.2 percent to 0.8 percent), and meningococcal conjugate (67.2 percent to 17.3 percent).

In New Brunswick, childhood immunizations were beginning to decline prior to the pandemic – 76.8 percent of children met immunization requirements on five mandatory vaccines (meningococcal conjugate, MMR, varicella, DTap and IPV) in 2018-2019, compared to 72.8 percent in 2019-2020. 

The importance of vaccinating children

Vaccines are safe and can prevent serious infectious diseases that at one time killed or seriously harmed children and adults. They work by using weakened or killed viruses or bacteria to trigger your child’s natural immune response to provide long-term protection against a disease, without the risk of getting the disease. Though many of these infectious diseases have been wiped out or nearly eradicated in Canada, they still exist in other parts of the world, and have been re-emerging in Canada periodically in recent years due in part to vaccine hesitancy and a growing complacency about the risks associated with preventable diseases. 

These diseases are life-threatening and can spread quickly among children and adolescents at school who are not or cannot be vaccinated due to certain medical conditions. It’s critical to ensure children are up to date on necessary vaccines. 

What vaccinations do children need?

Parents should ensure school-aged children are current on the following vaccines:


Diphtheria is a serious infection caused by strains of bacteria called Corynebacterium diphtheriae. The bacteria make a toxin that can make it difficult to breathe, and can lead to heart failure, paralysis, and even death.


Measles is a highly contagious, acute respiratory virus caused by a morbillivirus. It causes cold and flu-like symptoms including fever, cough, runny nose and sore throat, and a skin rash made up of slightly raised, small red spots. Measles can lead to a number of health complications, including diarrhea, ear infections, pneumonia, encephalitis and death.

Meningococcal disease 

Meningococcal disease is caused by bacteria called Neisseria meningitidis. It can lead to meningitis (bacteria infecting the lining of the brain and spinal cord) and septicemia (bacteria infecting the bloodstream), which are both very serious infections that can be deadly within hours.


Mumps is a contagious disease caused by a paramyxovirus. It impacts the salivary glands near the ears that can make it painful to chew or swallow. Though rare, complications from mumps can cause inflammation and swelling in the brain, nervous system and pancreas, and can lead to hearing loss and heart problems.

Pertussis (whooping cough)

Pertussis is a contagious infection of the lungs and airways caused by the bordetella pertussis bacteria. It causes thick mucus to accumulate in the airways that causes uncontrollable coughing and makes it difficult to breathe.


Polio is a disabling, life-threatening disease caused by the poliovirus. The virus infects the throat and intestines, causing flu-like symptoms and can spread to the brain and spine, causing nerve injury that leads to paralysis, difficulty breathing, and death.


Rubella is caused by the rubella virus. Symptoms are similar to measles, though they are caused by different viruses. Rubella causes a mild fever, headache, red, itchy eyes, enlarged lymph nodes at the base of the skull, and a fine, pink rash that begins on the face and spreads quickly to the torso, arms and legs.


Tetanus is an infection caused by bacteria called Clostridium tetani. When the bacteria invade your body, they produce a toxin that causes painful muscle contractions. Infections can cause a person’s neck and jaw muscles to lock (lockjaw), making it hard to open the mouth or swallow. Without treatment, tetanus can be fatal.

Varicella (chickenpox)

Varicella (chickenpox) is an infectious disease caused by the varicella-zoster virus. It causes an itchy, blister-like rash that first appears on the chest, back, and face, but can spread over the entire body. Chickenpox can be especially serious in babies and those with weakened immune systems.  

A detailed schedule of required vaccines for infants and children in all provinces and territories is available here.  

What’s behind vaccine hesitancy?

Though the majority of Canadian parents do choose to fully vaccinate their children, some are unsure or hesitant. A 2016 study found that most vaccine-hesitant parents are in the middle of the spectrum and underimmunze their children instead of not immunizing them at all. Reasoning behind vaccine hesitancy included lack of confidence (in effectiveness, safety, the system, or policymakers), complacency (perceived low risk of acquiring vaccine-preventable diseases and/or indifference about disease effects), and lack of convenience (accessibility, including time, place, language, and cultural contexts). 

Below are answers to common questions about routine childhood vaccines. 

Q: Can my child still get a disease even after being vaccinated?

Vaccines are one of the most effective weapons we have against disease. About 95 percent to 99 percent of children develop immunity after vaccination, which further improves with boosters. If your child does get sick, vaccinated children tend to get milder symptoms. 

Q: Why are these vaccines important if many of these diseases are no longer here?

Vaccines are the reason these diseases have been eliminated. Your child might never need the protection offered by vaccines, but you don’t want them lacking the protection in the event of an outbreak, which still occurs in Canada for diseases such as measles, mumps, and whooping cough. It’s also vital if you ever plan to do any international travel with your children, or if they are ever in contact with international travellers. 

Q: Are vaccines safe?

Yes. The safety of each vaccine is carefully checked and monitored on an ongoing basis. If a serious side effect is found, the vaccine is pulled from the market. The risks posed by these preventable diseases far outweigh any risk posed by vaccines.

Q: Can my child get a disease from the vaccine itself?

No. The majority of vaccines use inactivated or killed viruses or bacteria, making it impossible to get the disease. Live vaccines (chickenpox and MMR) contain viruses that are weakened and occasionally cause a mild case of disease (e.g., a few spots of what look like chickenpox or measles). This is not harmful and actually means that the vaccine is working.

Q: Are the ingredients in vaccines toxic?

Some ingredients in vaccines might be toxic, but only at much higher doses. Many substances, including water, can be toxic at high enough doses, and many healthy foods also contain toxic chemicals in small doses. For example, pears contain small amounts of formaldehyde. The ingredients in vaccines are there to keep them from getting contaminated by bacteria and to make them work better.

Q: Do vaccines cause autism?

No. Study after study has shown that vaccines do not cause autism. This misinformation comes from a small study in 1998 that suggested a link between vaccinations and autism spectrum disorder, however the study was reviewed further and retracted. The author’s medical license was also revoked due to falsified information.

Q. Does my child need vaccines if their classmates are all immunized?

The chance of catching a disease is low if everyone else is fully immunized, however they are exposed to children and people other than classmates. Each child who isn’t immunized gives these highly contagious, preventable diseases a chance to spread.

Q: Isn’t natural immunity better than vaccination? 

Although natural immunity might give better immunity than vaccines, the risks are much higher. With natural infections, a child might develop serious, sometimes life-threatening complications including permanent brain damage, deafness, blindness, and death. If your child is exposed to a disease after being vaccinated, their immune system is equipped to fight it off.

If your child has fallen behind on critical vaccines, talk to our doctors today about getting caught up.