VACCINE RESOURCE COMMITTEE

of the Edmonton Zone Medical Staff Association

View Full List of Vaccine Questions Here

Influenza Vaccine Question #2:

If someone never has influenza symptoms, why should they get the vaccine?

If someone has been lucky enough to never had a symptomatic influenza infection, this has no bearing on their risk of getting sick from influenza infection in the future. As someone ages, their risk profile for severe influenza infection may also increase due to age and comorbidities.  

Nearly 30% of people carrying the influenza virus have no symptoms. Getting the vaccine helps to protect close contacts; one should be vaccinated against influenza if they have a close contact who is at high risk of getting very sick from influenza, such as family members and caregivers.

Influenza can injure the body, making it vulnerable to developing new major illnesses. A study involving 26,000 people, published in the medical journal NEJM Evidence in July 2024, found that in the week following influenza infection, the inflammation caused by the virus destabilized plaques of atherosclerosis, causing clots to form. As a result, people were six times more likely to have heart attacks in the first week after getting influenza than these same people had been in the year before they got influenza and in the year after they recovered from it. Many of those people had not previously been diagnosed with heart disease.

Sources:

John Hopkins Medicine: 11 flu myths debunked
Alberta Health Services: Influenza (Flu) Vaccine
Harvard Health Publishing: Why do I need a flu or COVID vaccine?