Despite a mild flu season in the southern hemisphere, experts can't predict exactly what flu season will be like in the northern hemisphere -- including Canada.
The uncertainty should propel people to get vaccinated against the most common form of influenza in the world, infecting hundreds of millions of people each year, experts say.
"We are always very careful to let people know we don't know what's going to happen," Dr. Keiji Fukuda, head of the World Health Organization's Global Influenza Programme, told reporters Thursday.
"However, vaccination is by far the best means to protect yourself given that uncertainty."
Each year, the influenza vaccine is modified to include three strains that experts think will circulate that year.
Last year's flu vaccine was only about 44 per cent effective in North America because it only matched one of three strains that circulated.
This year's vaccine has three new strains and closely matches the vaccine that was available for winter season in the southern hemisphere. Fukuda told reporters the vaccine was a good match in the southern hemisphere and seems to have been effective.
It is rare for all three strains to change, which fuelled speculation that this year's season will be particularly harsh.
"We can never predict, this is what's the unfortunate part," Public Health Agency of Canada spokesperson Jacinthe Perras told CTV.ca. "Everything is done on the best scientific data, but beyond that we can never speculate."
Influenza is an infection in the airways that can cause fever, sneezing and runny nose, dry cough, fatigue and muscle aches.
It affects between 10 per cent and 25 per cent of Canadians each year, according to PHAC. Flu season generally runs between November and April.
The flu spreads easily around schools, businesses, nursing homes, hospitals and even cities as people cough and spread droplets of the virus into the air.
Most people recover from the flu within seven to 10 days.
However, 500,000 people worldwide die from the flu, Fukuda said.
Those who are most susceptible to becoming very sick or being hospitalized are those with weakened immune systems, the elderly and the very young.
"So the key message here, and the single most important thing that I'm going to say here, is that influenza vaccines can protect you, they can protect individuals and they can protect the people around you, including the people that you care most about," Fukuda said.
Experts say it's best to get vaccinated before flu season begins, which is why October is Influenza Immunization Awareness Month.
The National Advisory Committee on Influenza recommends that "priority be given to immunization of those persons at high risk of influenza-related complications, those capable of transmitting influenza to individuals at high risk of complications and those who provide essential community services. However, influenza is encouraged for all Canadians."
The average cost for the vaccine is about $20, although it is free in some provinces, according to the Canadian Coalition for Immunization Awareness & Promotion.
