Daily Archives: October 27, 2019

Influenza (The Flu) is a severe and potentially deadly viral upper respiratory tract infection. Influenza A and B are the two main strains of this virus that cause seasonal outbreaks. Both strains are extremely contagious with Influenza A typically causing the majority of outbreaks.

Microbiologists further classify each strain into subtypes based on surface proteins. For example, Influenza A subtypes that have caused widespread human disease over the past century are: H1, H2, H3, N1, N2.

Last year marked the 100-year anniversary of the Spanish Flu (H1N1) Pandemic of 1918 which claimed 50 million lives world wide. The Asian Flu (H2N2) Pandemic of 1957 claimed 1.1 million lives while 1968 pandemic (H3N2) was similarly responsible for another million deaths. Most recent pandemic still fresh on many people’s minds was the H1N1 pandemic of 2009. It claimed the lives of half a million people and was particularly severe in children and young adults.

Antigenic Drift: Influenza virus is constantly mutating (changing) its surface protein thereby fooling the body’s natural defences (antibodies). This ‘antigenic drift’ is the reason why each year microbiologists and epidemiologists design a new vaccine which will protect against the predominant circulating strain of the Flu.

Twice a year, the World Health Organization (WHO) organizes a consultation with laboratory researchers from around the world to determine the composition of the vaccine. The production of the vaccine takes at least 6 months and on occasions by the time the vaccine comes off the production line, the virus has mutated making the vaccine less effective than initially anticipated.

As you can appreciate, Flu vaccine production is costly and represents the pinnacle of scientific achievement and cooperation. Unfortunately, majority of Ontarians do not appreciate just how fortunate we are to be the recipient of this potentially life saving vaccines since the price tag is ‘free’. A vaccine that saves the life a 5-year old child or prevents the spread of the flu to a loved one receiving chemo therapy is priceless. It is time we all appreciate this fact and do the least we can do by getting a simple ‘jab’ yearly.

In the next blog I will answer frequently raised questions about the flu vaccine and go over the logistics of getting your shot this year.

Until then, keep it healthy!
Dr. Matin