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We are about half way through wintery weather conditions, which also means we are about half way through that pesky flu season.

With flu levels peaking this week, numbers are expecting to start declining and eventually dwindling off.

“We are actually seeing high levels of influenza activity right now, there is not much indication levels are starting to drop so we really are at the peak of influenza activity right now,” explains Interior Health Senior Medical Health Officer Dr. Andrew Larder. “I am hoping over the next week or so we will start to see the levels drop but they will stay elevated probably until the end of February.”

He says Interior Health is able to track the flu's movement and peak by the number of doctor visits for respiratory illness, along with the recent outbreaks at residential care facilities in the Okanagan.

“H3N2 tends to produce more severe outbreaks because it tends to cause more severe illness in older people and we are certainly seeing lots of that activity. I think we have around 15 or 16 outbreaks right now going on across the health authority,” says Larder who adds it has been an especially rough season for many residents.

“In terms of residential care facility outbreaks, we have actually had more outbreaks this year than we had the last time this strain of virus, H3N2, was circulating. So this actually is a more severe season that way.”

A big issue this year has been that this particular strain of flu, H3N2, has thwarted scientist's predictions and changed enough to nearly nullify the flu vaccine.

“There is certainly some evidence that because of the changes in the genetic makeup of the H3N2 that is circulating, the protection by this year's vaccine is really quite limited."

Larder says the flu shot is made with a virus that is as close a match as possible to the virus genetically that will circulate in the coming season. The vaccine production begins in February, so it is made months and months before the flu season, and therefore their genetic matchup doesn't always work perfectly.

“In that period between February and when the flu season starts, the virus that is circulating, the wild virus, can actually undergo changes in its genetic makeup and that is exactly what has happened,” says Larder. “So because it is slightly different genetically, the antibodies that are produced by the vaccine don't affect the virus as well as they should do.”

Which is good reason, he says, to get the vaccine every year as flu strains change constantly.

Although flu cases are expected to decline over the next few weeks, Larder recommends Okanagan residents still consider getting the flu shot, if they haven't already.

“It is still worth getting the shot because even a little bit of protection is better than none against H3N2, and you have to remember the vaccine actually provides protection against two other strains of influenza (A & B) as well.

While Influenza A is peaking right now, Larder warns that Influenza B tends to peak in February so there is still time to get the vaccine to protect yourself.