Calgary

Changing flu strain contributes to 40 Calgary outbreaks, 300 hospitalizations

A strain of influenza sweeping through Alberta this winter is a particularly serious one that can still sicken people who received a flu vaccination.

H3N2 a tricky strain that can change over the course of a flu season, expert says

Alberta Health Services has reported 1,036 confirmed cases of flu in Calgary. (CBC)

A strain of influenza sweeping through Alberta this winter is a particularly serious one that can still sicken people who received a flu vaccination.

Calgary has seen nearly 40 influenza outbreaks at hospitals and long-term care facilities since September. The bug that's hitting Albertans right now is Influenza A H3N2, according to Calgary's medical officer of health, Dr. Judy MacDonald.

"It's a more difficult one. It typically causes a little more severe illness, especially in the extremes of age," she said.     

It's also a tricky strain that can change over the course of a flu season, according to U of C infectious disease expert Glen Armstrong.

"That makes it a challenge to have a vaccine because you can generate a vaccine that is a perfect match for an H3N2 variant, and then as the flu season goes on that variant makes slight changes, which decreases the effectiveness of the vaccine as the flu season goes on," he said.

'You are still going to be better off'

Getting plenty of rest, washing your hands frequently, staying well hydrated and taking in some vitamin D outside, are all good ways to try and stay healthy during flu season, on top of getting the annual flu vaccine, he said.

"Even though you got your flu shot and maybe it isn't 100 per cent effective and you do get the flu, you are still going to be better off than if you weren't vaccinated in the first place. ... You aren't going to get as sick, and you are going to recover a lot more quickly," Armstrong said.

The Calgary zone has seen 1,036 lab-confirmed cases of influenza, according to AHS. More than 300 Calgarians have been hospitalized with lab-confirmed cases of influenza.

Armstrong says while it's hard to predict what will happen this winter, typically once cases of Influenza A start to drop off, Influenza B steps up to take its turn.

Of the 13 Albertans who have died with lab-confirmed influenza, five of them were from the Calgary area.

There were 55 influenza-related deaths reported in Alberta during last year's flu season.