Influenza (Flu) Season

Influenza, also called the flu, is an infection of the upper airway caused by an influenza virus. Every year there is a period of time when there are more outbreaks of the flu. This is called the flu season. Flu season generally occurs during the fall, winter and early spring.

Understanding the seasonal flu, including the health complications the flu can cause and who is at risk, can help prevent you and your family from becoming sick.

Getting sick with the flu can put you at risk of getting other infections. These include viral or bacterial pneumonia, which affects the lungs. The risk of complications can be life-threatening. People at higher risk of complications include

  • Senior 65 years and older
  • Very young children
  • People who have lung or heart diseases, certain chronic health conditions or weakened immune systems

In Canada, thousands of people are hospitalized and may die from the flu and its complications during years with widespread or epidemic influenza activity.

How can you prevent the flu?

The influenza vaccine is a safe and effective way to help prevent you and your family from getting sick. It can even save lives.

In addition to getting the flu vaccine, you can help stop the spread of the flu by:

  • Washing your hands regularly
  • Promptly disposing of used tissues in the waste basket or garbage
  • Coughing and sneezing into your shirt sleeve rather than your hands
  • Staying home when you are ill
  • Keeping your hands away from your face
  • Keeping common surface areas like doorknobs, light switches and keyboards, clean and disinfected
  • Eating healthy foods and staying physically active to keep your immune system strong

What is in the flu vaccine?

The 2018-19 seasonal trivalent and quadrivalent vaccines contain:

  • A/Michigan/45/2015 (H1N1)pdm09-like virus
  • A/Singapore/INFIMH-16-0019/2016 (H3N2)-like virus
  • B/Colorado/06/2017-like virus
  • B/Phuket/3073/2013-like virus (in quadrivalent vaccines only)

The A/Singapore and B/Colorado strains were not contained in the 2017/18 season vaccine.

There are several inactivated influenza vaccines and a live attenuated influenza vaccine available in B.C. The inactivated vaccines are made of killed influenza viruses and are given by injection. The live attenuated influenza vaccine is made from weakened influenza viruses and is given as a nasal spray.

Publicly-funded influenza vaccines available in B.C. for 2018/19:

  • Trivalent Inactivated Influenza Vaccines (TIIV or TIV)
    • Influvac® (Mylan Pharmaceuticals)
    • Fluviral® (GlaxoSmithKline)
  • Quadrivalent Inactivated Influenza Vaccines (QIIV or QIV)
    • Fluzone® Quadrivalent (Sanofi Pasteur Limited)
  • Quadrivalent Live Attenuated Influenza Vaccine (LAIV-Q)
    • Flumist® Quadrivalent (AstraZeneca Canada)

To learn more about this year’s seasonal influenza vaccine, visit ImmunizeBC - Influenza and BCCDC: 2018/19 Seasonal Influenza Vaccines.

Pharmacists Can Administer Vaccines in B.C.

Ask your community pharmacist if they can administer the vaccines to you. Pharmacists who are trained and certified by the College of Pharmacists of B.C.can administer immunization for subcutaneous, intradermal and intramuscular injections to those 5 years of age and older and intranasal route to those 2 years and older.

Important Vaccine Information

Vaccine Eligibility

To learn who is eligible to receive the flu vaccines for free, visit BCCDC: 2018/19 Seasonal Influenza Vaccines Eligibility.

Individuals with Neurologic or Neurodevelopment Conditions

Influenza immunization is particularly recommended for children and adults with neurologic and neurodevelopmental conditions.

People with egg allergies

People with egg allergies can be safely immunized with the live and inactivated influenza vaccines.

Flu Information for Specific Groups

Adults 65 Years of Age and Older

Fluzone High-Dose is a high dose trivalent inactivated influenza vaccine approved for use in Canada for adults 65 years of age and older. The high-dose vaccine is expected to be more effective than the standard vaccination. While the standard vaccine is free, Fluzone High-Dose is not publically funded in B.C. at this time. If interested, the vaccine is available at pharmacies throughout B.C.  for an extra cost. For more information on Fluzone High-Dose Influenza Vaccine visit BCCDC: Fluzone® High-Dose Influenza Question and Answer Document Updated - August 2018.

Children and adolescents 2 to 17 years of age

NACI recommends using a quadrivalent formulation of influenza vaccine for children and adolescents 2 to 17 years of age. If a quadrivalent vaccine is not available, use trivalent inactivated influenza vaccine (TIV). For children who have not had a bad reaction to the vaccine, any of the following vaccines can be used:

  • Quadrivalent live attenuated influenza vaccine (LAIV)
  • Quadrivalent inactivated influenza vaccine (QIV)
  • Trivalent inactivated influenza vaccine (TIV)

Live Attenuated Influenza Vaccine (the nasal spray vaccine): Parents may have heard different reports about the live attenuated influenza vaccine. Canada's National Advisory Committee on Immunization has reviewed the most recent research on the effectiveness of this vaccine. They continue to recommend this vaccine as a safe and effective option for children 2 to 17 years of age. For more information see: HealthLinkBC File Number:12e Live Attenuated Influenza (Flu) Vaccine

For Health Care Workers and other Providers in Facilities and Community Settings

B.C. has an Influenza Prevention Policy to protect people at high risk from influenza. People at high risk include

  • Health care workers
  • Regular visitors
  • Emergency response workers
  • People who have contact with residents of continuing care or long-term care facilities or residences
  • People who provide home care for persons in high-risk groups
  • Students of related health care services

Health care workers, visitors, contractors and volunteers are required to be immunized against influenza or wear a mask when they are in patient care areas during the influenza season. This section provides information and resources about the influenza prevention policy for health care workers. The links and following information are for your general information. Please speak to your supervisor if you are a health care worker about how this program applies to your facility or role.

NACI recommends that health care workers get TIV or QIV instead of LAIV for two reasons. The most important reason is that TIV is more effective according to comparative studies in persons 18 to 59 years of age. The second reason is that LAIV recipients should avoid close contact with persons with severe immune compromising conditions for at least two weeks after vaccination. Examples include bone marrow transplant recipients requiring isolation. While the risk is low, there is a theoretical risk of transmitting a vaccine virus and causing infection.

Influenza Policies and programs

People in direct contact with poultry infected with Avian Influenza H5N1 (Bird Flu)

Avian Influenza (H5N1), also known as the "bird flu", commonly causes sickness in birds. People are rarely infected. It is different from the seasonal flu and there is low risk of human to human transmission. NACI recommends immunization against seasonal influenza for people in direct contact with poultry infected with an avian influenza during culling operations. The Public Health Agency of Canada and BCCDC have more information about H5N1 for the general public. For more information see: Public Health Agency of Canada: Avian Influenza (H5N1): Global Update

Featured Topics

Influenza (Flu)

To learn about the flu, how to prevent it, what the symptoms are, what the home treatments are and more, click on the link below.

Influenza (Flu) Vaccinations

Influenza vaccines are a safe and effective way to help people stay healthy, prevent illness and even save lives. To learn about the inactivated influenza vaccine, the live attenuated influenza vaccine, myths and facts about influenza immunization and the benefits of getting the vaccine, click on the links below.

Pneumococcal Vaccinations

Pneumococcal infection is caused by a germ or bacteria. It can cause serious and life-threatening infections. These infections include

  • Meningitis, an infection of the lining that covers the brain
  • Septicemia, an infection of the blood

To learn more about the vaccines that can help protect against pneumococcal infection, click on the links below.

Washing Your Hands

Hand washing is one of the best ways to keep yourself and others healthy. Regularly washing your hands can help stop the spread of germs that cause the flu. To learn more, click on the link below.

Useful Websites

BC Centre for Disease Control

BCCDC provides health promotion and prevention services, and diagnostic and treatment services to reduce communicable and chronic disease, preventable injury and environmental health risks. BCCDC also provides analytical and policy support to government and health authorities.


ImmunizeBC works to reduce the number of infections by vaccine-preventable diseases in B.C. ImmunizeBC provides information on immunizations to individuals, families and health care providers. They also provide tools to make it easier for B.C. families to get immunized. For information on where you can locate flu clinics across the province or to learn more about the flu and the flu vaccine, click on the links below.

Government of Canada

Get answers to many questions about the seasonal flu, including causes, symptoms, risks, treatment and prevention.


Last Reviewed October 4, 2018

Information in the Influenza Health Feature is adapted from Health Canada - National Advisory Committee on Immunization, accessed September 27, 2018, the BCCDC: Vaccines in BC, accessed September 27, 2018 and ImmunizeBC - Influenza, accessed September 27, 2018.

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

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