Public health officials are warning this could be a nasty flu season in Ontario for a couple of reasons.
The influenza type A strain making the rounds results in more severe illness and this year’s vaccine, which is developed months in advance isn’t as good a match if the flu strains it’s meant to fight have drifted or changed.
Ontario Public Health officials say the predominant flu strain this season is H3N2, a virus that results in more hospitalizations and deaths.
As of Dec. 6, there have been 342 confirmed flu cases in Ontario, a figure nearly double the 182 this time last year. Toronto has seen 113 cases, more than three times the 10-year seasonal average.
The flu shot, when it’s a good match, is usually about 60 per cent effective in preventing illness but this year it’s likely only about 40 per cent effective.
Even so, Dr. Bryna Warshawsky of Public Health Ontario says the vaccine is still the most important way of protecting yourself against the flu.
“If I said to you that you have a 40 per cent chance of winning a lottery, you’ll think that’s a fairly good odd and want to buy a lot of tickets.”
10 must-know things about the seasonal flu
1. Public Health Ontario says the seasonal flu is a disease that the public is likely to encounter each year between November and April.
2. There are two types of seasonal flu: (A and B); Type A has two subtypes: H1N1 and H3N2, while type B has two lineages called Yamagata and Victoria.
3. The seasonal flu vaccine contains one strain from each influenza A subtype and strains from one or both B lineages.
4. Each year, the virus affects 10 per cent of the population.
5. Symptoms of the seasonal flu, which usually begin one to four days after exposure, include fever, coughing, runny nose, muscle aches, fatigue and sore throat.
6. The flu virus spreads by droplets from those coughing and by contact of surfaces where the virus can survive for hours.
7. The flu has a short incubation period of one to three days and generally lasts two to seven days.
8. For some people, including those with chronic diseases of the heart and lung, pregnant women, the elderly or the very young, the flu can cause some serious complications such as pneumonia.
9. Each year in Canada about 12,200 people are hospitalized with the flu and about 3,500 die from it.
10. The National Advisory Committee on Immunization recommends that everyone gets the flu shot.
With files from The Canadian Press