Flu Fighters: How Canada influences the development of the annual flu shot

Winter is just around the corner, and with it, is the dreaded annual flu season. Most Canadians know how important it is to get the flu shot to help protect from getting sick, but have you ever found yourself wondering how the yearly influenza vaccine is developed? You might be surprised to learn about the amount of work that goes into that small immune-boosting, lifesaving vial.

Flu researchers at the Public Health Agency of Canada (PHAC) are always on the lookout for different strains of influenza virus so they can understand how it spreads throughout Canada and around the world.

Figuring out the flu strains

“Selecting the vaccine is an international effort,” said Dr. Nathalie Bastien, Research Scientist at the PHAC’s National Microbiology Laboratory (NML). “There are 112 national influenza centres around the world and all of us are busy doing lab surveillance all year long. This work helps to monitor the characteristics of the current flu viruses that are circulating so that we can prepare for the next flu season.”

It all starts at the local level where doctor’s offices, clinics, and hospitals will send samples to provincial laboratories, who then send them on to the NML.

“Researchers at every stage have a different responsibility when it comes to flu surveillance,” says Dr. Bastien. “Regional and provincial labs manage frontline diagnostics and the NML conducts further analysis of the strains to detect changes in influenza viruses.”

“We also produce quality assurance materials for the provinces so that they are prepared to detect emerging strains around the world in case they arrive in Canada.”

Each national influenza centre sends a selection of the most prevalent flu strains in its country to the nearest World Health Organization (WHO) collaborating centre for influenza. Once a year, all these centres meet to analyze their collective data to determine how to make the most effective vaccine for the next season. After that, development of the next annual flu shot begins.

How you can help track the flu

While NML flu researchers are busy in the lab, PHAC epidemiologists are using state-of-the-art tools to track the spread of influenza across the country and around the world. They track when and where influenza and influenza-like-illnesses are happening and determine the groups of people who are most affected by them. The results of these surveillance activities can be found in their weekly FluWatch report.

The FluWatch program consists of a network of labs, hospitals, doctors’ offices and provincial/territorial ministries of health. PHAC epidemiologists also rely on data reported by the public to figure out where the flu is spreading and to look for signals of high or unusual flu activity.

Canadians from across the country can sign up to become Fluwatchers. By taking just 15 seconds to answer questions each week during the flu season, Fluwatchers help our epidemiologists track the virus in Canada.

“Data from our Fluwatchers is so important because it paints a picture of how the flu is affecting people in different regions of the country,” said Claire Sevenhuysen, an Epidemiologist with FluWatch.

Getting your annual flu shot is the most effective way to protect yourself against the flu and flu-related complications. The more people get vaccinated against the flu, the lower the chance of catching the flu and spreading it in the community. “Getting vaccinated protects you and those around you who may be too young or unable to receive the flu shot,” said Ms. Sevenhuysen. “Even if you are healthy, having the flu makes you feel like you got hit by a truck. The annual flu shot can reduce your chance of getting the flu and may reduce the severity of symptoms even if you still get the flu, so it’s worth it!”