As Canadians prepare for another flu season, infectious disease experts are sticking with recommending widespread vaccination despite a study suggesting its benefits may have been overstated.

Every year, flu experts make an educated guess about which flu strains end up being the most common before deciding which ones to include in the vaccine the following year.

For 2007, flu experts chose the wrong ones, said Dr. Don Low, microbiologist in chief at Toronto's Mount Sinai Hospital.

"As a result, we had quite a robust year for influenza," Low said.

For this year's vaccine, scientists went back to the drawing board. In a rare move, they identified three new strains, instead of the usual one or two, and developed a new combination that they hope will work better, Low said.

Low and other infectious disease experts agree it is still important for everyone to get a flu shot.

Last month, Dr. Sumit Majumdar of the University of Alberta Hospital published a study that concluded the flu vaccine may not be as effective at protecting seniors from complications such as pneumonia as believed.

"There's a common slogan that says: "Every 200 jabs saves a life,'" Majumdar told CBC News. "And that's not true."

Majumdar's research suggested the vaccine reduced mortality by 19 per cent.

But the flu shot still saves lives, as well as reduces sickness and hospital admissions, Low noted.

If the general population is immunized, then less of the virus circulates, which means it is less likely that elderly people will be exposed, he added.

Majumdar said the key is that seniors should not rely on the flu vaccine alone.

He likened the protection of flu shots to using an umbrella when it's raining to avoid getting wet: the vaccine won't offer complete protection, but it's better than just putting a newspaper over your head or walking out without anything.

Majumdar also suggested that seniors:

• Avoid family members who are sick, such as sniffling grandchildren.
• Stay clear of visiting hospitals during flu season.
• Using tissues, instead of handkerchiefs, and throwing out each tissue after one use.
• Be vigilant about handwashing to prevent the virus from spreading onto surfaces like doorknobs.

For Jack Carter, 99, the flu shot is worth a little sore arm.

Carter, who grew up in Newfoundland and now lives in Halifax, remembers the flu pandemic that started in 1918, when millions died worldwide, and whole communities were wiped out.

"I think every person had the flu except my grandfather," recalled Carter, who has already had his flu shot this season. "My grandfather never got it."

There are more than 2000 flu-related deaths in Canada every year. Seniors, people with weak immune systems and some children are at highest risk.

Possible side-effects of getting vaccinated can include fever, muscle pain and weakness.