Flu Shot Linked with Stroke Prevention

An annual flu shot is recommended for everyone over 6 months of age with rare exceptions, and it is especially important for people, including older adults, who are at a higher risk for serious complications from the flu.  Adults with certain chronic health conditions such as asthma, heart disease and stroke, diabetes and chronic kidney disease are also at higher risk for serious illness, hospitalization or death as a result of the flu.  A new study out of Canada’s University of Calgary has also found a strong protective effect the flu vaccine provides in preventing stroke. 

The study, published in The Lancet Public Health, builds on the established scientific connection between influenza infection and stroke.  Upper respiratory tract infections have long been associated with stroke, leading researchers to study a decade of health records data to determine if the flu shot lowered the risk of stroke among Albertans. 

There is also an existing medical link between influenza and heart attack, making the study into the risk for stroke a logical next step for researchers.  Researchers found that not only was the risk lower for stroke in the six months following adult patients receiving their flu shot, there was a protective effect despite any underlying chronic health conditions.  Researcher and professor Dr. Michael D Hill told Global News the connection between stroke or heart attack and upper respiratory infections like influenza or strep could also apply to COVID-19. 

Specific bacteria or viruses that infect the lungs or bronchioles can also lead to plaque in the carotid artery.  Preventing upper respiratory infections can also help reduce the risk for ischemic stroke – a bonus protective factor of getting an annual flu shot.  While it’s considered ideal to get your flu shot by end of October, it’s not too late for flu vaccination for protection from serious illness over the remainder of the fall and winter.   Vaccination can also help lighten the burden for already stressed hospital systems. 

People aged 65 and older may be candidates for a high-dose flu vaccine to boost the immune system response and offer greater protection from infection and serious health complications.  Talk with your doctor to determine which flu vaccine is appropriate for your age and any underlying health conditions.