This year’s strain of influenza A is a virulent form of H3N2 – more severe than last year’s – and comparable in severity to the 2014-15 flu season.
I’ve done seven ER shifts since just before Christmas, and in every one I diagnosed influenza. In years gone by, I would have made the diagnosis based on signs and symptoms. These days, we can make a precise diagnosis by taking a swab where the back of the nose where it joins the throat or pharynx. Just about every swab I’ve ordered during the past two weeks has tested positive for the flu. That tracks with reports from health officials that there was a big uptick in cases over the holidays. I’ve seen patients of all ages, but seniors have been affected disproportionately – some requiring admission to hospital.
According to the latest figures from Flu Watch Canada, there have been nearly 2000 cases confirmed in the lab, but likely many more Canadians have or have had the flu. There are widespread outbreaks in parts of BC, Alberta and Saskatchewan – with lots of localized outbreaks in those provinces and Ontario.
BC’s Interior Health Authority said last week that as many as fifteen deaths may be linked to an outbreak affecting seventeen care facilities in the region. Calgary is dealing with close to forty outbreaks with over a thousand confirmed cases and more than 300 hospitalised. Across Alberta, there have been more than a dozen flu-related deaths. As of last week, there were 115 cases of H3N2 in Ottawa – making it one of Ontario’s hardest hit cities. And they’re just starting to see cases of flu in New Brunswick
Experts believe that this year’s flu shot is a close genetic match against H3N2 – which means it should be much more effective. One expert told me the current flu shot at least 50 per cent effective.
Keep in mind though that 20 percent of the most vulnerable seniors don’t get the shot. Combine that with a 50 percent effectiveness rate, and the bottom line is that we’re going to see frail seniors with severe respiratory distress who have to be admitted to hospital – with some ending up in the ICU on a ventilator.
Unfortunately, when it comes to getting the flu shot, Canadians are getting mixed messages. Public health officials and commercials tell you to get the shot. But the vaccine is far from 100 per cent effective. Last years, flu shot had less than 10 per cent effectiveness against H3N2 – the worst in a decade. One expert speculated that an annual flu shot might leave you vulnerable to a bad strain down the road.
A friend of mine brought her kids to the pediatrician for a check up and asked whether they should get the shot. He was downright blasé about it.
The solution is a universal flu vaccine that is given once and protects against the flu for ten years or more. Researchers are getting closer, but we’re not there yet. New high dose preparations of influenza vaccines have recently become available. By giving greater immunity to frail seniors, they can help reduce the death rate in vulnerable people. Meanwhile, this year’s flu shot is effective enough for me to recommend that you get it – to protect you – and especially people at risk.
Brian Goldman is an ER physician in Toronto and host of White Coat Black Art. Catch his weekly house doctor columns on afternoon shows across Canada.