The H1N1 pandemic that struck Canada and much of the rest of the world in 2009 seems increasingly like a distant memory.  Now, a new strain of flu has begun to hit parts of Canada with a vengeance.  Yet here's the thing.  Parts of Canada are in the grip of a type of seasonal flu that for some is every bit as serious as H1N1.

I worked quite a few shifts in the ER over the holiday period.  Every shift, I saw as many as 8-10 patients and sometimes more with symptoms of the flu.  In early December, we were doing nasal swabs of every patient with flu like symptoms.  But, when more than 50% of the swabs started coming back positive for H3N2, it became pointless to do them since numbers like that mean that virtually every patient coming to the ER with flu-like symptoms has the flu.  Virtually every senior who I thought had pneumonia in fact had the flu.  Many of them had to be admitted to hospital.  They were that sick.  And that's just the thing.  In 2009, I worked during H1N1 and in the past few weeks, I worked during a major outbreak of H3N2 seasonal flu.  I haven't seen much of a difference in severity.  The only difference I've seen is that with H1N1, the majority of those who got very sick were young, whereas with H3N2, the majority getting really sick has been seniors.

This new strain called H3N2 is a seasonal strain of flu rather than a pandemic strain.  The distinction is more than semantics.  Seasonal flus are similar enough to recent strains of flu over the past few years that a large proportion of the population that got the flu over the past 2 or 3 years will have partial immunity to this one.  A pandemic strain is so different from recent flu strains that virtually no one has complete or even partial immunity to it.

Toronto Public Health says influenza appears to be hitting hard earlier than usual this season in Toronto, compared to other regular non-pandemic flu years. As of last week there were more than 500 laboratory-confirmed cases of H3N2, compared to an average of about 81 cases per year. Five deaths have been recorded in the Greater Toronto Area, and 1000 cases in all of Ontario.  There's a fair amount of flu activity in the corridor from Windsor, Ontario to Montreal.  Outbreaks have been reported at long-term care facilities in Winnipeg, with visitors warned to stay away if they're coughing and experiencing other flu symptoms.  According to The Public Health Agency of Canada's most recent figures, more flu has been spreading in southern Ontario, parts of southern Quebec and in southern Manitoba in the past couple of weeks.

A number of studies have indicated that fewer Canadians have gotten this year's flu shot.  For instance, Toronto public health officials say 20 percent fewer people received this year's flu shot compared to the years 2008 and 2009.  Vaccination rates are down in other parts of Canada too.  This is a carryover from H1N1, in which a total of 11 million Canadians or 41% of the eligible population got the vaccine.  As of now, only 25% of Ontarians have gotten the shot, so we're down below the poor showing during H1N1.  This is enlightened speculation, but public health officials fear that the H3N2 is more widespread and more severe simply because fewer Canadians have gotten the flu shot.

So, why aren't more Canadians getting the flu shot?  Some might believe that the H1N1 vaccine protects against H3N2.  It doesn't.  The only way to receive specific immune protection against H3N2 is to get this year's seasonal flu shot.

The other possible reason may be more telling.  I believe that vaccination rates during H1N1 - while not high - were higher than they are now because Canadians were led to believe that H1N1 was going to be one serious virus.  For most people, it wasn't.  So, when it came time for people to consider getting this year's seasonal flu shot, many just shrugged.

I was certainly not a proponent of the fear mongering we witnessed during H1N1.  But that doesn't mean I'm against vaccines.  The single most important thing Canadians should do is getting a flu shot.  It's not 100% effective, but is proven to help prevent the flu or at the very least make the flu they do get milder.  People suspected having the flu should see their doctor.  Typical symptoms include fever, malaise, sore throat, dry cough, and severe muscular aches and pains.  The drug Tamiflu helps reduce the duration and the severity of the flu if started within 48 hours of the first symptoms.  Wash your hands thoroughly or use hand sanitizer frequently if you get the flu or are in close contact with someone with the flu.