The Current

This year's flu shot may be ineffective, but you should still get it, argues Dr. Brian Goldman

Australia confirmed 217,000 cases of H3N2 from June until August, and discovered the vaccine used was only 10 per cent effective.
It's turning into a particularly bad flu season around the world. In North America, what has so-far been considered a 'moderately severe' flu season is expected to get worse. (

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Has the flu got you?

This flu season is turning into a particularly nasty one as Canada, the U.S. and other parts of the world battle epidemic levels of the illness, overwhelming hospitals.

And what has so-far been considered a "moderately severe" flu season in North America, is expected to get worse. 

The particular strain of Influenza A, H3N2, is predominant right now, says Dr. Brian Goldman, an emergency room physician and host of CBC Radio's White Coat Black Art. 

"H3N2 tends to cause more serious flu. This strain has been responsible for more than 1,000 hospitalizations and at least 34 deaths in Canada," Goldman tells The Current's Anna Maria Tremonti.

While Canada has reported 11,000 cases of the flu, with that number rising, Goldman says last year Australia confirmed 217,000 cases of H3N2 from June until August — over double the previous record of 100,000 cases reported in 2015.

Dr. Goldman recommends getting an annual flu shot regardless of its effectiveness and says to get the vaccine early in the season because it takes two weeks for the immune system to develop antibodies against the flu viruses. (CBC Radio )

The vaccine used in Australia was only 10 per cent effective, says Goldman and it's still unclear if this will be the case in Canada.

"The CDC — Center for Disease Control in the United States — is still hopeful that it could be as much as 30, 40 per cent effective. But I wouldn't be surprised if it's that ineffective."

Why bother with the flu shot?

With a low efficacy rate, it's hard to sell the flu vaccine as a proactive measure against catching H232.

But Goldman argues there's a growing belief that even in seasons when a flu shot is relatively ineffective, getting the vaccine boosts something called cell-mediated immunity. 

"Now cell-mediated immunity won't keep you from getting the flu. But it probably will keep you from getting the most severe consequences of the flu," Goldman tells Tremonti.

A Canadian Medical Association Journal suggests repeated flu vaccinations in seniors can preventing severe and fatal influenza. (Bebeto Matthews/Associated Press)

This week, the Canadian Medical Association Journal published a study that suggests repeated flu shots in older adults reduces the severity of influenza.

"If seniors receive a flu shot annually, every year without fail, they are half as likely to require admission to hospital, half as likely to die, half as likely to suffer the consequences," Goldman explains. 

"The important thing about this is that cell-mediated immunity is the mechanism that researchers hope will end up in our ... having a permanent durable vaccine."

Goldman suggests focusing on never getting the flu may be the wrong goal to aim for in the long-term.

"Maybe the goal is to make sure that nobody has to die of the flu,  or as few as possible will die of the flu," he says, adding that's where the research on this is heading.

From Australia, to Europe, and across North America, this flu season has been a deadly one.

Australia's aggressive outbreak saw over 93,000 people fall ill last September alone.  

In France, nearly 12,000 people were hospitalised and 30 people died as a result of the flu over the holidays. 

In the U.K, the cities of London and Dorchester are considered the only two places with no reported cases. 

The city of Calgary is considered the epicentre of Alberta's flu outbreak with more hospitalizations and deaths than any other part of the province. The number of flu cases in Calgary, compared to the same time period last year, is 100 per cent higher, according to Dr. Eddy Lang.

Listen to the full segment at the top of this post — which includes an expert in infectious diseases, Dr. Amesh Adalja, on how vaccines are made and why vaccines are not more effective.

This segment was produced by The Current's Lara O'Brien and Samira Mohyeddin.