Common questions about vaccines

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Are vaccines safe?

Yes. Vaccines are given to prevent certain diseases. They are held to the highest standards of safety and are among the safest things we put into our bodies.

All vaccines have possible side effects. Most side effects are mild, such as fever, or tenderness and swelling where the needle or injection is given, and have no long term effects. Occasionally there will be a more serious reaction to a vaccine, such as an allergic reaction, but long term effects are rare.

  • In Alberta, all reactions are reported to Alberta Health and Wellness shortly after the reaction occurs. This ensures that we are able to monitor reactions and react quickly to address any concerns that may arise.

If vaccines cause side effects, wouldn’t it be “safer” to just avoid them?

Unfortunately, choosing to avoid vaccines is not a risk-free choice – it is a choice to take a different and much more serious risk.

  • Stopping immunization can lead to disease rates going up.

In most instances the risks from getting the disease are much greater than the risk of reaction to a vaccine. For example, whooping cough (pertussis) still occurs in Alberta – stopping to breathe, seizures and pneumonia are a few of the complications that result from this infection.

How are vaccines made and licensed in Canada?

Vaccines for humans are regulated in Canada by the Biologics and Genetic Therapeutics Directorate (BGTD) of Health Canada. Like all medications, vaccines must undergo several stages of rigorous testing before they are approved for use.

BGTD supervises all aspects of vaccine production by the manufacturers. Before any vaccine is licensed and approved for use in Canada, the factory where it is manufactured must be inspected to ensure that all stages of production meet the requirements for safety, sterility and quality control.

  • Before release by the manufacturer, each batch of vaccine is tested for safety. Most safety tests are carried out by both the manufacturer and, independently, by BGTD.
  • Once vaccines are in use, Canada has several systems in place to ensure that they are carefully monitored for safety and that any problems are dealt with quickly.

What would happen if we stopped immunizing?

Experience from other countries shows that rates of disease increase when fewer people are immunized:

  • In Ireland when measles immunization rates dropped to around 76 per cent, measles soared to more than 1,200 cases in the year 2000, as compared with just 148 the previous year. Several children died in this outbreak due to complications from measles disease.
  • Between 1990 and 1995 due to a drop in immunization rates, over 100,000 cases of diphtheria with 1,200 deaths occurred in Russia and Ukraine. Previously, Russia had only a few cases of diphtheria each year and no deaths. Diphtheria toxoid came into routine use in the 1930s, but even today diphtheria remains a serious disease. About one person in 10 with diphtheria still dies in spite of medical treatment.
  • In Japan, pertussis vaccine coverage dropped from 90 per cent because of public concern over two infant deaths that followed DPT immunization. Prior to the drop in coverage there were 200 to 400 cases of pertussis each year in Japan. From 1976 to 1979, following the marked drop in vaccine coverage, there were 13,000 cases of pertussis with over 100 deaths. Similar situations occurred in the United Kingdom and Sweden when their immunization rates dropped or programs were stopped. Once Sweden restarted pertussis immunization programs, the number of reported cases fell once again.

Do vaccines weaken the immune system?

No. Vaccines strengthen the immune system to protect infants, children and adults from specific diseases. Infants and children are exposed to many kinds of germs every day, through eating, drinking and playing.

The vaccines recommended for children and adults use only a small portion of the immune system's capacity. Scientists estimate that the immune system can respond to about 10,000 different things at any one time. Immunization does not add much to the daily immune response even for a 2 month old infant. Vaccines given at two, four and six months of age use less than 0.01 per cent of an infant’s immune response.

  • Infants need to be protected with vaccines because they are more likely to get very sick from the diseases that vaccines can prevent, such as diphtheria, whooping cough and meningitis.

The recommended immunization schedule for infants in Alberta is carefully developed to ensure that they are protected safely from vaccine preventable diseases at appropriate ages.

Can giving a child several vaccines at the same time overload the immune system?

No. Vaccines used today are more highly purified than those in the past, so even though infants and children now receive more vaccines than in the past, the total number of vaccine substances and proteins they are exposed to now is much lower.

  • In Alberta, infants and children routinely receive immunizations against several diseases in one injection and usually receive several injections at each clinic visit.
  • Vaccines go through extensive testing to assess the effect of giving them at the same time.
  • Only vaccines that have been shown to be safe and effective when given together are administered at the same time.

Protecting against several diseases at one time keeps children safe by protecting them against more diseases sooner. As an added benefit, it also reduces children's discomfort by reducing the number of injections they receive, and it saves parents the time and expense of additional office visits.

Where do I go to get immunizations?

For information on where to get immunizations, call Health Link Alberta: