# 4013
The Public Health Agency of Canada produces a weekly influenza summary called FluWatch, which is very similar to the US FluView report from the CDC. In it you will find maps, charts, and summaries of the previous week’s influenza surveillance.
As in the United States, Canada is in the midst of a serious outbreak of influenza, more befitting of what might be expected in January or February than early November.
A few excerpts from this week’s report (ending Nov 7th), but follow the FluWatch link to read it in its entirety.
Summary of FluWatch Findings for the
Week ending November 7, 2009
- Nationally, there was a considerable increase in the influenza activity level reported this week with a proportion of positive influenza tests of more than 38%, the national ILI consultation rate of almost 100 per 1,000 patient visits, 25 regions reporting widespread activity and over 750 influenza outbreaks reported. This increased activity occurred in almost all provinces and territories.
- The Pandemic (H1N1) 2009 strain accounted for nearly 100% (99.8%) of the positive influenza A subtyped specimens.
- The intensity of Pandemic (H1N1) 2009 in the population was high with 1,324 hospitalizations and 35 deaths reported this week. Hospitalized cases were reported in all provinces and territories that sent the weekly data2 except MB and NU while the deaths were from all P/T except NB, PE, NT and NU. From August 30 to November 7, 2009, a total of 2,295 hospitalized cases including 317 cases admitted to an intensive care unit (ICU) (13.8%) as well as 59 deaths had been reported. Numbers of new deaths were four times higher than last week.
- So far, the proportion of severe cases (ICU admissions and deaths) among all hospitalized cases was lower than in the period up to August 29, 2009.
- The activity levels reported during the previous weeks were even higher than the peak period of the first wave (e.g. the three first weeks of June, 2009).
Overall Influenza Summary - Week 44 (November 1 to November 7, 2009)
Nationally, there was a considerable increase in the influenza activity level reported this week with a proportion of positive influenza tests of more than 38%, the national ILI consultation rate of almost 100 per 1,000 patient visits, 25 regions reporting widespread activity and over 750 influenza outbreaks reported. This increased activity occurred in almost all provinces and territories.
Twenty-five regions reported widespread activity in BC, AB, SK, ON, QC, PE, NS & NL and fifteen regions in MB, ON, QC, NB & NL reported localized activity, while thirteen regions reported sporadic activity in MB, ON, QC, NB, NS, NL, YK, NT & NU and one region in NU reported no activity. The 755 influenza outbreaks reported this week were all in schools except 22 in hospitals and residential institutions (BC, AB, ON, QC, NB & NL) and 10 in an unspecified location (AB, MB, ON & PE). The schools outbreaks were in NS (173), BC (157), SK (150), AB (148), PE (47), NB (45), NL (2) and MB (1). Note that this is the first year that all the provinces and territories are reporting on influenza outbreaks in schools (greater than 10% absenteeism on any day most likely due to ILI) which is increasing considerably the total number of outbreaks reported compared to the previous years.
Canadian situation
Antigenic Characterization
Since September 1, 2009, NML has antigenically characterized 70 Pandemic (H1N1) 2009 viruses and two seasonal influenza viruses (one influenza A/H1N1 and one B virus) that were received from Canadian laboratories. All 70 Pandemic influenza A (H1N1) viruses characterized were antigenically related to A/California/7/2009, which is the pandemic reference virus selected by WHO as Pandemic (H1N1) 2009 vaccine. The one seasonal influenza A/H1N1 virus characterized was related to A/Brisbane/59/07, which is the influenza A/H1N1 component recommended for the 2009-10 influenza vaccine. The one influenza B virus characterized was antigenically related to B/Brisbane/60/08, which is the recommended influenza B component for the 2009-10 influenza vaccine.
Antiviral Resistance
NML: Pandemic (H1N1) 2009 viruses tested so far have been sensitive to zanamivir (70 samples) but resistant to amantadine (62 samples). Of the 69 Pandemic (H1N1) 2009 viruses tested, 67 were sensitive to oseltamivir and two viruses were resistant to oseltamivir with the H275Y mutation. The two resistant cases were associated with oseltamivir treatment.
Provinces: Three cases of oseltamivir resistant Pandemic (H1N1) 2009 were reported to date in Canada from the province of Quebec on July 21, 2009, from Alberta on September 15, 2009 and from Ontario on October 13, 2009.
