A Teen’s Guide to Vaccination
Organization: Public Health Agency of Canada
Date published: 2023-03-17
Getting vaccinated is an important way to keep ourselves safe and healthy from serious and life-threatening diseases. The best way to protect ourselves is by making sure we get all recommended vaccines on time.
Table of contents
- About vaccination
- Diseases prevented by routine vaccinations
- Vaccine safety
- Staying up to date with your vaccination
- What to expect at your vaccination appointment
- Where to find more information
What are vaccines?
Vaccines are tools that work with the body's natural defences (the immune system) to develop protection against diseases without the risks that come from getting the diseases.
What is the immune system?
The immune system is a complex network of cells, tissues and organs in our bodies that work together to help prevent diseases and keep us healthy.
Our immune system responds to things it considers unfamiliar or harmful, such as bacteria and viruses that can cause diseases. Through a series of steps called the immune response, our bodies produce antibodies and immune memory cells to fight the infection and provide protection against future infections (immunity).
Antibodies are proteins that attach to harmful bacteria or viruses and help to remove them from the body. If we encounter that specific virus or bacterium again, immune memory cells quickly produce more antibodies to help remove it from the body before we get really sick.
Did you know? Many bacteria are useful and can be naturally found in and on our body without making us sick, as long as they aren't in parts of the body where they don't belong. It's part of our immune system's job to determine which bacteria can make us sick and to develop an immune response if needed.
How does vaccination work?
Vaccination works by exposing our bodies to key parts of bacteria or viruses, called antigens, in a safe way so our immune system can develop an immune response. Later, if we are exposed to that same bacterium or virus, our immune system will be able to respond more quickly to:
- prevent us from getting the disease
- prevent us from getting seriously ill if we do get the disease
How are vaccines given?
Most vaccines are given by an injection (a needle) into the upper arm. Some vaccines can be given orally (by mouth) and there's a flu (influenza) vaccine that's sprayed into the nose.
Some vaccines offer life-long protection, while others require booster doses to continue providing protection.
Some vaccines protect against only one virus or bacterium, while combination vaccines protect against several at the same time. Combination vaccines are helpful as they mean fewer injections and fewer appointments, which can help reduce delays in getting vaccinated and building protection.
Why is vaccination important?
Vaccination is considered one of our most important public health tools. Over the past 50 years, vaccination has saved many lives in Canada and around the world. Some diseases that were once common in Canada are now rare because of vaccines. Vaccination can even completely stop a disease from occurring anywhere in the world. For example, there hasn't been a single case of naturally occurring smallpox in the entire world since 1977, thanks to vaccination.
Some vaccines can help to create community immunity (also known as herd immunity). This means that the more people who have been vaccinated against a disease, the less chance there is of the disease spreading in a community. This helps protect people who can't be vaccinated. It also helps protect those for whom the vaccine may not work as well, such as infants, older adults and people who are immunocompromised.
People who are immunocompromised have a weakened immune system due to a health condition or medications they take. They may not be able to receive certain vaccines, and the vaccines that they can receive may not work as well. These people are at higher risk of getting vaccine-preventable diseases and becoming very ill.
Getting vaccinated and staying up to date with your vaccines helps protect people who are immunocompromised from vaccine-preventable diseases.
Did you know? The more contagious a disease is, the more people need to be vaccinated to prevent it from spreading. For example, measles is one of the most contagious diseases: even a single case of measles can spread quickly when people aren't vaccinated. In a group of 100 people who have never had a measles infection, 95 of them need to be vaccinated to prevent measles from spreading. This is why vaccination rates have to stay high to prevent outbreaks.
To compare the number of cases of 6 vaccine-preventable diseases before and after vaccines were introduced in Canada, check out the Vaccines Work Poster.
Diseases prevented by routine vaccinations
Routine vaccinations are recommended on a schedule based on age. No matter where you live in Canada, all or almost all of these vaccines are provided for free by your province or territory.
These are some of the diseases that routine vaccinations can help protect you from. Some are given as combination vaccines:
- flu (influenza)
- hepatitis B
- HPV (human papillomavirus)
- whooping cough (pertussis)
The timing of vaccines may vary depending on your province or territory of residence. Some vaccines may be offered at school, while others are offered at your doctor's office or at a pharmacy. Talk to your parents or caregivers, a health care provider or your local public health department about which vaccinations you need and where you can get them.
Other vaccines may also be recommended in certain situations. For example:
- if you're travelling to an area where certain viruses or bacteria are common
- if you may have been exposed to certain viruses or bacteria, for example, due to exposure to an infected person or animal or a contaminated object
- during an outbreak of a disease
- if you have certain health conditions or risk factors
Are you travelling?
Some diseases that aren't common in Canada are common in other parts of the world. This means that when you travel to another country, you could be exposed to viruses and bacteria that we don't routinely vaccinate against in Canada.
It is recommended that you consult a qualified travel health provider or visit a travel health clinic at least 6 weeks before your trip. They might recommend other vaccinations based on where you are traveling to.
Visit travel vaccinations for helpful travel advice and information.
Yearly flu (influenza) vaccination
Influenza is a respiratory illness that can cause fever, cough, muscle aches, headaches, sore throat and tiredness. Some people only get mildly ill, while others can get very sick.
Everyone aged 6 months and older is recommended to get an influenza vaccine every fall. This is because protection from the influenza vaccine may not last from one year to the next and the strains in the vaccine can change from year to year. Influenza vaccines target the 3 or 4 influenza strains that are expected to cause illness in the upcoming influenza season (November to April).
By getting your influenza vaccine, you can protect yourself and others too, since you'll be less likely to spread influenza to them.
For more information, talk to your health care provider, local public health department or visit our web page on flu.
COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. It can cause no symptoms or mild to severe illness. You can help protect yourself from getting very sick with COVID-19 by getting vaccinated.
Visit COVID-19 vaccines to learn more.
Human papillomavirus (HPV) is a common sexually transmitted virus. There are many different types of HPV. Most HPV infections cause no symptoms and resolve on their own within a couple of years. Some HPV types can cause genital warts. Others can cause changes in the cells, which sometimes lead to cervical cancer or some cancers of the throat, mouth, penis, anus, vagina or vulva.
You can protect yourself and your sexual partner from the types of HPV that most commonly cause cancers and warts by getting the HPV vaccine. It's often offered at school clinics. Practicing safer sex, such as always using a condom, is also very important to help prevent sexually transmitted infections.
Did you know? Changes in the cells of the cervix from HPV infection can require treatments to prevent them from turning into cancer. These treatments can be uncomfortable and can sometimes cause complications in future pregnancies. Preventing HPV infection through vaccination prevents these changes in the cervix.
When a vaccine is being considered for approval, Health Canada reviews how well the vaccine works and its safety before making a decision.
Once a vaccine has been approved, Health Canada continues to monitor its safety and its effectiveness, in cooperation with provinces and territories, other countries and international agencies.
After being vaccinated, it's common to have side effects that may last for 1 to 3 days. Common side effects of vaccines can include pain, swelling and redness where the injection was given, mild fever, tiredness, and headaches.
Did you know? You may have mild side effects for a few days after vaccination because your body is working to develop an immune response against the disease.
Some people may be afraid to receive a vaccine. Some people feel faint during or after vaccination. For tips on reducing pain, preventing fainting and making vaccination a more positive experience, see the section What to expect at your vaccination appointment.
Very rarely, someone may have an allergic reaction to a vaccine. If you suspect you might be having a serious reaction after a vaccination, seek medical care right away. Serious side effects from vaccines should also be reported to the local public health department. Tell your health care provider about any serious reactions you've experienced before you receive future vaccinations.
Staying up to date with your vaccination
How do you know if you're due for a vaccine?
Vaccine schedules (also referred to as immunization schedules) set by provinces and territories are designed to provide protection before you're most at risk for vaccine-preventable diseases.
Everyone should maintain a personal vaccination record throughout their life. Keep it in a safe place and present it at every vaccination appointment so it can be updated. Ask your parents or caregivers about your personal vaccination record. Your health care provider or local public health department can also help you find it or give you one if you don't already have one.
Staying up to date on your vaccinations is important throughout your life, as different vaccines are recommended at different ages. In addition, schools, including colleges and universities, might require you to be up to date on your vaccines in order to attend.
You can find out if you've had recommended vaccines by comparing your personal vaccination record to the recommended vaccination schedule in your province or territory of residence, or by talking with a health care provider or your local public health department.
How can you get vaccinated?
To find out where to get vaccinated, you can ask your parents, caregivers, a health care provider or your local public health department. Some vaccines may be offered at your school, while others are offered at a health care provider's office or a pharmacy.
What if you missed a vaccine?
If you haven't gotten all recommended vaccines, you can still catch up. It's important to get back on schedule.
Your parents, caregivers, a health care provider or your local public health department can help you figure out:
- which vaccines you've already had
- which ones you still need
- when and where to get them
What to expect at your vaccination appointment
Before your appointment
- Plan ahead to make the vaccination experience a more positive one.
- Consider bringing something to keep your mind off the vaccination, such as an electronic device, music or video.
- Wear short sleeves or a loose-fitting top.
- Don't skip a meal before going to the appointment.
- If you have fears or anxiety about vaccination, reach out to your health care provider before the appointment to talk about options that might help you.
- If the vaccine is being offered at school and you would prefer to receive it at your health care provider's office or a community clinic, ask if that can be arranged.
- Bring your personal vaccination record with you to your appointment. If you don't have one, ask for one at your appointment.
During your appointment
Your health care provider may ask you a few health questions before you get vaccinated. This is a great time to ask any questions you have about vaccines.
If you tend to faint during medical procedures or have had a serious reaction after a previous vaccination, tell the person giving you the vaccine. If you have a fear of needles or any other concerns, discuss them with the health care provider.
For a more comfortable vaccination experience, try the following strategies:
- sit upright, or lie down if you prefer
- try to keep your arm as relaxed as possible
- try relaxation techniques such as deep belly breathing
- take deep breaths into your belly; breathe in through your nose and out through your mouth
- distract yourself with an electronic device, music or video
- if you feel dizzy or faint, tell the health care provider
- they will help you lie down on your back and bend your knees
Did you know? You can use the CARD system (Comfort, Ask, Relax, Distract) to find more strategies to help improve the vaccination experience. Learn more about the CARD system.
Before leaving the clinic
Remind your health care provider to record the vaccination in your personal vaccination record. If you don't have one, ask for one now.
Make an appointment for your next vaccination if that is needed.
You'll be asked to wait for at least 15 minutes after the vaccination to make sure you don't have an allergic reaction or feel faint.
Serious allergic reactions to vaccines are very rare. Signs of a serious allergic reaction may include:
- breathing problems (wheezing)
- swelling of the face, tongue or throat
- red rash on the skin (hives)
If you think you're having a serious allergic reaction while at the clinic or in school, alert a staff member right away. They will have medication on hand to manage allergic reactions.
After the vaccination
Minor side effects can occur after vaccination, including:
- pain, swelling and redness at the injection site
- mild fever
These reactions are normal and usually go away within a few days. You can take medication if needed for pain or fever. Check with your parent or caregiver or your health care provider if you need advice about which medication to use.
When to call a health care provider after vaccination
If you have symptoms that could be an allergic reaction, seek immediate medical attention. If you are in school, tell your teacher right away. If you are at home, tell your parent or caregiver right away. If you have other symptoms that are getting worse or not going away, or you're worried about something, contact your health care provider or seek medical attention.
Where to find more information
Your health care provider or local public health department can provide you with more information on vaccines.
Did you know? Misinformation is false or misleading information that is presented as fact. Disinformation is misinformation that is deliberately created and spread to deceive or mislead people. Misinformation and disinformation about vaccines are common. Be sure to get your information about vaccines from trusted and reputable sources.
Here are some websites you can trust for vaccine information:
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