Have you ever wondered why there is a flu 'season'

Shots aren't available until Monday but flu season is already underway.

Of the 54 cases of influenza confirmed in Alberta so far this fall — including 30 in Calgary — 17 have resulted in admission to hospital.

Have you ever wondered why there is a flu 'season'?

"There are a few things we think are causing a season to colds and flu," Dr. Raj Bhardwaj, an urgent care doctor and family physician told the Calgary Eyeopener.

"One is that we're inside more of the time, we're swapping spit more, we're leaving secretions and sharing them around more... the windows are closed and there's not as much draft."

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And just as we have an immune system to keep us healthy, viruses have ways of protecting themselves too.

"The flu has this protective coating around it, I like to think of it as a buttery coating or a little chocolate coating, and that coating, if it's too warm, will melt, then the flu virus inside actually degrades," said Bhardwaj.

"But when it's cold, instead of melting, it actually hardens, so then the virus can sit on surfaces and survive a lot longer."

Sneezes travel further in winter

The air being drier during winter also helps the viruses proliferate.

"When you sneeze or cough, those virus particles get thrown up in the air, if the air is moist, those little particles pick up moisture and they get heavy and land, so they don't disperse so far. And once it lands the little coat melts and you're good to go, in the summer. In the winter it's got a nice hard shell, you sneeze, it doesn't pick up as much moisture from the air so it floats around and goes way further. A sneeze in summer might only affect a few feet and a sneeze in the winter can go for metres and metres."

Giving shots earlier would put people at risk later in the year when immunity wears off.

"We know it takes one or two weeks to build immunity once you get a flu shot, but we also know that immunity doesn't last forever and the flu season lasts well into the spring," he said.

"So if you get your flu shot too early, then you're not going to be protected in the late flu season, which can be just as bad."

There's also the small matter of giving out millions of vaccines being a giant logistical nightmare.

"You've got to get all the flu vaccine dispersed and it's got to be refrigerated the entire time to make sure the flu vaccine is still good when we actually inject it into people," said Bhardwaj.

"And we have to get it into all the corners of the province and ready to go on the same day."

Not all flu shots created equal

Albertans should know which shot to get this year.

"For everyone between six months and 65 years of age, the first choice is a shot that covers four different strains of influenza and it's called Fluzone," said Bhardwaj.

"For folks greater than 65, there's a different one, called FLUAD, so it's the flu vaccine plus an adjuvant, which actually boosts the immune system's response to the flu vaccine."

There will be four clinics offering flu shots beginning at 11 a.m. Monday:

• Brentwood Village Mall (3630 Brentwood Rd. N.W.)
• Northgate (A154 495 36 St. N.E.)
• Richmond Road Diagnostic Centre (302 1820 Richmond Rd. S.W.)
• South Calgary Health Centre (31 Sunpark Plaza S.E.)

Shots will also be available free of charge from most family doctor's offices and most pharmacies, however children under nine years old will have to get it from an AHS clinic. 

With files from the Calgary Eyeopener