Dr. Brenda Coleman has a simple answer when asked who needs a flu vaccine: “Everyone.” Dr. Coleman is a clinical scientist at Mount Sinai Hospital in Toronto and says that because the flu can be transmitted before we realize we have it, it’s important to get the vaccine.

According to the Public Health Agency of Canada, there were over 55,000 confirmed influenza cases in the 2017-2018 fall/winter season. “Some ignore the vaccine because they believe that if they get the flu, they’ll only be sick for a few days and will bounce back just fine,” says Dr. Coleman. “That isn’t the case for everyone.”

The flu season this year was particularly harsh, leading to greater calls for the elderly and other high-risk populations to get vaccinated. In the most extreme circumstances, complications from the flu can lead to hospitalization or death.

Vaccine improvements on the horizon

When it comes to understanding why the flu season was so bad, the answer often lies in the process of cultivating the vaccine through egg adaptation. Until recently, the best place to cultivate influenza viruses used in vaccines was in chicken eggs, notes Dr. Allison McGeer, a Medical Director of Infection Control at Mount Sinai Hospital.

“But chicken eggs are not human,” says Dr. McGeer. “So when you introduce human viruses, they recognize that the environment is different.” This means that though the virus has the structure needed for the vaccine, it can adapt to its new surroundings which can reduce efficacy. Fortunately, new vaccines currently available in the US, have been developed without egg adaptation to overcome this issue and hopefully, improve the efficacy of vaccination.

Enhanced vaccines, including adjuvanted vaccines, which offer enhanced protection through boosting antibody production, have become available in Canada in recent years. In Australia and the U.K., they’re the recommended vaccine for people aged 65 and over, as they offer extra protection for weaker immune systems against virus mutations.

To stay safe this flu season, ask your doctor and/or pharmacist if you’re a candidate for the enhanced flu vaccine. Adults  with elderly parents should be especially vocal in advocating for their parents to receive the most effective vaccinations available. “Whether you’ve got the vaccine in past years or it’s your first time, get your flu shot,” Dr. Coleman says. “Some protection is better than none.”