Immunization : Your Best Protection


What is a vaccine?

A vaccine is a substance that primes the body’s immune system to make antibodies, T-cells and memory cells which are the body’s defense against infection. When you are vaccinated you actually build up your immune system, making you stronger and more resistant to disease as you grow.  Vaccines are the best way to protect you and your family against some very serious infections.  The National Advisory Committee on Immunization and the Canadian Pediatric Society strongly recommend routine immunization.

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What is vaccination?

Vaccination means having the vaccine − actually getting the injection.

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What is immunization?

Immunization means both receiving the vaccine and becoming immune to ward off a disease as a result of immunization.

Like eating well and exercise, getting immunized is a foundation for a healthy life.

Immunizations help save lives, prevent serious illnesses, and are recognized as one of the most effective public health interventions. Immunizations help the body make its own protection (or antibodies) against certain diseases. In Ontario, immunizations are given against rotavirus, diphtheria, pertussis (whooping cough), tetanus, polio, haemophilus influenzae type b (Hib), measles, mumps and rubella (German measles). Immunizations may also be given against hepatitis, influenza, chickenpox, meningococcal disease, pneumococcal disease and human papillomavirus. There are also a number of vaccines for other circumstances, for example, people traveling to a country with diseases that are not common in Canada, such as typhoid fever.

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Why is immunization important?

When children are immunized, their bodies make antibodies that fight specific infections. If they are not protected and come in contact with one of these infections, they may get very sick and potentially experience complications, or even die.

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How effective are vaccines?

Vaccines are very effective in preventing disease when given as recommended. However, no vaccine will work for 100 per cent of the children who receive it. Studies of disease outbreaks show that although some immunized children can develop the infection, the illness is often less severe.

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How safe are vaccines?

All vaccines have to be tested to make sure they are both safe and effective. The most common side effects are mild pain, swelling and redness where the injection was given.

Some infant vaccines may cause a low-grade fever (approximately 38°C) or fussiness for a day or two after the injection. Physicians may recommend acetaminophen to prevent fever and pain. Serious side effects from immunizations are rare. Please report any side effects or severe vaccine reactions to your health care provider or local public health unit. You should always discuss the benefits and risks of any vaccine with your health care provider.

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Is immunization required for attendance at school or day care in Ontario?

For children attending school in Ontario, a written immunization record or proof of immunization is required, by law, for diphtheria, tetanus, polio, measles, mumps and rubella unless there is a valid written exemption. Parents/guardians are required to provide this information to their local public health unit, and to update the information as necessary.

Children attending licensed childcare centres should be immunized according to their age and as recommended in the Publicly Funded Immunization Schedules for Ontario – August 2011. You may contact your local public health unit for more information.

You may decide because of medical, religious or philosophical reasons not to immunize your child. In this case, you will need to provide a valid written exemption to your local public health unit. If the disease appears in your child's school or childcare centre, your child may have to stay out of school/childcare until the disease is no longer present.

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Where to get immunized :

Call your doctor or nurse practitioner to make an appointment. If you don't have a physician, nurse practitioner or health card, call your local public health unit to find out where you or your child can get immunized.

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When to get immunized :

Recommended routine immunizations begin at two months of age to protect infants from illnesses that can be very serious for them. The following chart outlines the schedule for publicly funded vaccines in Ontario available for children beginning their routine immunization in early infancy.

Publicly Funded Routine Immunization Schedule for Children Beginning Immunization in Early Infancy

Download the Publicly Funded Immunization Schedules for Ontario (August 2011) [PDF]

Vaccines that protect against the following diseases are available free of charge, and are required for attendance at school (unless there is a valid written exemption) :


Vaccines against the following diseases are recommended but not required for attendance at school. These vaccines are available free of charge :


Vaccines against the following diseases are recommended for younger children. These vaccines are available free of charge :


Talk to your doctor or nurse practitioner for more information on these vaccines and the diseases they prevent.

It is important to keep an immunization record.

Get a yellow immunization card from your doctor, nurse practitioner or local public health unit to keep a record of the vaccines you and your child have received. An up-to-date immunization record will prevent unnecessary extra shots. Written immunization records are needed when :


It is the parent/guardian's responsibility to provide immunization records for all school children to the local public health unit. Don't forget to update the health unit when/if your child gets another shot.

Always remember :

Because of changes in the influenza (flu) strains, adults also need to receive the flu shot each year.

In addition, all adults 19 to 64 years of age, not immunized in adolescence, are now eligible to receive one lifetime dose of the tetanus, diphtheria and pertussis vaccine to replace a dose of the tetanus and diphtheria vaccine. Parents of newborns, infants and young children are considered a priority to receive the pertussis-containing vaccine.

Adults should continue to get the tetanus and diphtheria vaccine every 10 years throughout life, to be protected against these diseases.

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Thinking about getting pregnant?

Be sure you are protected against rubella before pregnancy to protect your future baby from serious problems during its development.

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For further information

For further information about immunization, or any other health topics, please contact your local public health unit or doctor/nurse practitioner.

Additional Immunization Links


Recommended Resources

To learn more about immunization, visit your local bookstores or library for the following books :

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For More Information

Call ServiceOntario, Infoline at 1-866-532-3161
In Toronto, 416-314-5518
TTY 1-800-387-5559
In Toronto, TTY 416-327-4282
Hours of operation : 8:30am - 5:00pm



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