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Inactivated influenza (flu) vaccine

Last Updated: September 25, 2023
HealthLinkBC File Number: 12d
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What is the inactivated influenza vaccine?

The inactivated influenza vaccine is made of killed influenza viruses or parts of the viruses. It protects against infection from influenza viruses and is given by injection. The vaccine does not protect against other viruses that cause colds or gastroenteritis (vomiting and diarrhea). Several different influenza vaccines are available in B.C., including a live attenuated influenza vaccine made from weakened influenza viruses that is given as a nasal spray. For more information, see HealthLinkBC File #12e Live Attenuated Influenza (Flu) Vaccine. All of the vaccines are approved by Health Canada.

In B.C., influenza vaccines are usually available beginning in October. For your best protection, get immunized as soon as possible. You can find information on booking an appointment to get immunized on the Government of British Columbia’s website at

Who should get the vaccine?

The influenza vaccine is available at no charge and recommended for everyone 6 months of age and older. The vaccine is especially recommended for people who are at high risk of serious illness from influenza and those able to spread influenza to those at high risk.

People at high risk of serious illness from influenza, include:

  • Children 6 months to less than 5 years of age
  • Pregnant people at any stage of pregnancy
  • Seniors 65 years and older
  • Residents of any age living in residential care, assisted living or other group facilities
  • Children and teenagers required to take Aspirin® or ASA for long periods of time due to a medical condition
  • Children and adults with certain medical conditions, including:
    • Heart or lung disorders that require regular medical care, such as asthma, chronic obstructive pulmonary disease or cystic fibrosis
    • Kidney disease, chronic liver disease such as hepatitis, diabetes, cancer, anemia or weakened immune system
    • Those with health conditions causing difficulty breathing, swallowing or a risk of choking on food or fluids, such as people with severe brain damage, spinal cord injury, seizures or neuromuscular disorders
  • Children and adults who are very obese

Indigenous Peoples may be at increased risk of serious illness from influenza due to health inequities resulting from colonialism.

People able to spread influenza to those at high risk of serious illness from influenza including:

  • Household contacts (including children) of people at high risk
  • Household contacts, caregivers and daycare staff of children under 5 years of age
  • Doctors, nurses and others working in health care settings, including long-term care facilities, who have contact with patients
  • Visitors to health care facilities and other patient care locations
  • Inmates of provincial correctional institutions
  • Those who provide care or service to people at high risk in potential outbreak settings such as cruise ships

Other groups who the vaccine is specifically recommended for include:

  • People who provide essential community services, including police officers, firefighters, ambulance attendants, and corrections workers
  • People working with live poultry

How is the vaccine given?

The vaccine is given by injection, usually as 1 dose. Children under 9 years of age who have never had an influenza vaccine need 2 doses given 4 weeks apart. The second dose improves their level of protection.

What are the benefits of getting the vaccine?

The vaccine is the best way to protect against influenza, a serious and sometimes fatal infection. When you get immunized, you help protect others as well by reducing the spread of the influenza virus.

What are the possible reactions after the vaccine?

Common reactions to the vaccine include soreness, redness and swelling where the vaccine was given. Other symptoms, that may last 1 to 2 days, can include:

  • Fever
  • Headache
  • Muscle or joint soreness
  • Fatigue
  • Nausea
  • Vomiting
  • Diarrhea
  • Chills

Babies and young children may be irritable, sleepy and have a decreased appetite. Fewer than 1 in 20 people may have oculo-respiratory syndrome (ORS). Symptoms of ORS include red eyes, a cough and/or sore throat and/or hoarseness.

You cannot get influenza from the inactivated influenza vaccine because it does not contain live influenza virus.

Acetaminophen (e.g. Tylenol®) or ibuprofen* (e.g. Advil®) can be given for fever or soreness. ASA (e.g. Aspirin®) should not be given to anyone under 18 years of age due to the risk of Reye Syndrome.
*Ibuprofen should not be given to children under 6 months of age without first speaking to your health care provider.

For more information on Reye Syndrome, see HealthLinkBC File #84 Reye Syndrome.

It is important to stay in the clinic for 15 minutes after getting any vaccine. There is an extremely rare possibility of a life-threatening allergic reaction called anaphylaxis. This happens in less than 1 in a million people who get the vaccine. Symptoms may include hives, difficulty breathing, or swelling of the throat, tongue or lips. If this reaction occurs, your health care provider is prepared to treat it. Emergency treatment includes administration of epinephrine (adrenaline) and transfer by ambulance to the nearest emergency department. If symptoms develop after you leave the clinic, call 9-1-1 or the local emergency number.

Guillain-Barré Syndrome (GBS) is a rare condition that can result in weakness and paralysis of the body’s muscles. It most commonly occurs after infections. In rare cases GBS can also occur after some vaccines. GBS may be associated with influenza vaccine in about 1 per million recipients.

Always report serious or unexpected reactions to your health care provider.

After getting the influenza vaccine, you might be contacted to participate in a study monitoring the safety of the vaccine. To learn more about the study please visit

Who should not get the vaccine?

Speak with your health care provider if you:

  • Had a life-threatening reaction to a previous dose of influenza vaccine or any part of the vaccine (people with egg allergies can be safely immunized)
  • Had severe oculo-respiratory syndrome after a previous dose of influenza vaccine
  • Developed GBS within 8 weeks of getting any influenza vaccine without another cause being identified

Children less than 6 months of age should not get the vaccine because it is not known to be effective at this age.

There is no need to delay getting immunized because of a cold or other mild illness. However, if you have concerns speak with your health care provider.

What is influenza?

Influenza is an infection of the respiratory system caused by the influenza virus. A person with influenza is at risk of other infections, including viral or bacterial pneumonia which is an infection of the lungs.

Influenza spreads easily from person-to-person through coughing, sneezing or having face-to-face contact. The virus can also spread when you touch tiny droplets from a cough or sneeze on another person or object, and then touch your eyes, mouth or nose before washing your hands.

What is the influenza prevention policy?

B.C. has an Influenza Prevention Policy to protect high risk people from influenza. Health care workers are required to be immunized against influenza or wear a mask when they are in patient care areas during the influenza season. Students, volunteers and visitors to health care facilities and other patient care locations are also expected to wear a mask if they did not get an influenza vaccine.

Mature minor consent

It is recommended that parents or guardians and their children discuss consent for immunization. Children under the age of 19, who are able to understand the benefits and possible reactions for each vaccine and the risk of not getting immunized, can legally consent to or refuse immunizations. For more information on mature minor consent, see HealthLinkBC File #119 The Infants Act, Mature Minor Consent and Immunization.

For more information

For more information, see the following HeathLinkBC Files:

For more information on immunizations, visit ImmunizeBC at