Flu vaccine sequel

TORONTO - Flu activity is picking up in some parts of Canada, but the predominant strain in this country is H3N2 instead of the pandemic H1N1 virus that dominated the health-care scene a year ago.

Dr. Irene Armstrong of Toronto Public Health says influenza appears to be hitting hard earlier this season in Toronto, compared to other regular non-pandemic flu years. The number of lab-confirmed cases so far is 515, she said, compared to an average of about 81 cases per year at this point from 2004-05 to 2008-09. Five deaths have been recorded.

"We know our hospitals are busy," Armstrong said in an interview Tuesday. "We're seeing outbreaks in long-term care homes, and especially over the last couple of weeks."

Outbreaks have been reported at long-term care facilities in Winnipeg and other centres as well, with would-be visitors warned to stay away if they're coughing and experiencing other flu symptoms.

Dr. Ken Scott of the Public Health Agency of Canada said flu is fairly widespread in one region of Manitoba and there's localized activity in other parts of Manitoba, Alberta, Quebec and Nova Scotia.

"We didn't have some reporting from some of the jurisdictions over the holiday season, but in the week just prior to that there was a fair bit of activity in the Windsor to Montreal corridor," noted Scott, senior medical adviser for Infectious Diseases and Prevention Control.

Statistics compiled by the national agency as of Tuesday show 4,112 samples tested, with 927 showing up positive for flu. These don't necessarily include the most up-to-date numbers from the provinces and territories. Furthermore, Armstrong explained these would only be the "tip of the iceberg" and most cases are never lab-confirmed.

Scott said the predominant strain in Canada and the United States is H3N2 influenza A, while H1N1 is "not a big player in Canada this year," representing less than 10 per cent of isolates.

By comparison, Great Britain's flu activity is almost all the H1N1 pandemic strain, he said. Scott surmised it could be because their H1N1 vaccine uptake last year was about eight per cent, much less than the 45 per cent in Canada.

He said the good news is that the flu shot this year can protect against both.

But there are concerns in the health community that fewer people are opting for a flu shot this year.

For example, Armstrong said 230,000 people were vaccinated with pandemic H1N1 vaccine at the city's public clinics last flu season from Oct. 26 to Jan. 31.

This flu season, fewer than 26,000 people have received shots at the Toronto clinics, which is even down about 20 per cent from a regular seasonal flu year, she said.

"There's certainly been a lot of speculation about people reflecting on their experience last year with the pandemic H1N1 influenza," she said, referring to widespread public education campaigns and media attention to flu shots a year ago.

"We had a mild pandemic ... So I think it's sort of fallen off people's radar."

Scott said H3N2 has a predilection for the young and the old, pregnant women and people who have underlying medical conditions.

Flu seasons with H3N2 tend to cause more illnesses than the seasonal H1N1 (non-pandemic) virus, he noted, adding that weather could also be a factor in how the flu season goes.

Scott said flu kills between 2,000 and 8,000 Canadians every year, and he recommended that everybody get a flu shot.

Armstrong agreed, and both public health officials said the messages of the pandemic flu campaigns can help now, too.

"If you're sick with flu symptoms, you should stay home from work or stay home from school," Armstrong advised.

"You don't want to go out and risk infecting friends or co-workers or other people out in the community, so it's best to stay home and rest, really, and treat your symptoms."

Symptoms include fever, headache, muscle aches, extreme tiredness and cough.