# 2123
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’s flu numbers this week are declining.
A few excerpts from this week’s report (ending Nov 21st), but follow the FluWatch link to read it in its entirety.
Summary of FluWatch Findings for the
Week ending November 28, 2009
- Nationally, the activity levels reported this week continued to decrease compared to the previous week.
- All FluWatch influenza indicators declined during week 47.
- The Pandemic (H1N1) 2009 strain accounted for nearly 100% of the positive influenza A subtyped specimens this week.
- The intensity of Pandemic (H1N1) 2009 in the population was moderately high with 804 hospitalizations, 139 ICU admissions and 56 deaths reported this week. Hospitalized cases occurred in all provinces and territories (P/T) that reported this week while the deaths were from all P/T except PE and 3 territories. From August 30 to November 28, 2009, a total of 6,314 hospitalized cases including 957 (15.2%) cases admitted to an intensive care unit (ICU) as well as 259 deaths had been reported.
- The proportion of severe cases (ICU admissions and deaths) among all hospitalized cases was lower in the second wave than in the first wave.
- A slight decline has been experienced in all provinces and territories as indicated in the continued decreasing number of reported hospitalized cases, ICU admissions and deaths reported this week.
Canadian situation
Antigenic Characterization
Since September 1, 2009, National Microbiology Laboratory (NML) has antigenically characterized 374 Pandemic (H1N1) 2009 viruses and five seasonal influenza viruses (two influenza A/H1N1, two H3N2, and one B virus) that were received from Canadian laboratories. Of the 374 pandemic influenza A (H1N1) viruses characterized, 372 (99.5%) were antigenically related to A/California/7/2009, which is the pandemic reference virus selected by WHO as the 2009 H1N1 vaccine. Two viruses (0.5%) tested showed reduced titer with antisera produced against A/California/7/09. Sequence analysis of the HA showed that the two viruses with reduced titer did not have the mutation at amino acid position 222 as reported by Norway. CDC also reported that of the 348 Pandemic (H1N1) 2009 viruses tested, one virus showed reduced titer with antisera produced against A/California/7/09.
Antiviral Resistance
NML: Pandemic (H1N1) 2009 viruses tested so far have been sensitive to zanamivir (351 samples) but resistant to amantadine (369 samples). Of the 361 Pandemic (H1N1) 2009 viruses tested, 358 were sensitive to oseltamivir and three viruses were resistant to oseltamivir with the H275Y mutation. The three resistant cases, 2 from Ontario and 1 from Quebec, 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.
