Canada:
Week 35 was officially the first week of the 2002-2003 respiratory viruses detection season and likewise the first week of the 2002-2003 influenza surveillance season in Canada (25 August 2002 to 23 August, 2003). Sentinel surveillance of influenza-like illness will resume during the first week in October and will continue year round thereafter. Influenza activity has remained at very low levels throughout the summer and into the fall. During the 2 week report period, Health Canada received 895 reports of laboratory tests for influenza. Less than one percent of tests (three of 895), were positive for influenza A. There were no detections of influenza B (see table below). Two of the three influenza A laboratory detections were associated with an outbreak of influenza-like illness (ILI) in a long-term care facility in Peel Region, Ontario. The outbreak began on 17 August 2002 (at the end of the 2001-2002 season). No additional reporting of ILI in staff, residents or in the general population has been reported since. Characterization of outbreak viruses is pending culture and referral due to low titres of the initial isolates. Detection of other respiratory viruses circulating in the Canadian population were also at low levels during the 2 week period, including: RSV (0.9% of tests positive), parainfluenza viruses (3.6% of tests positive) and adenovirus (2.4% of tests positive), see line graph.

International:
On 31 August 2002, The World Health Organization (WHO) posted the latest update on an outbreak of influenza in Madagascar, which began during the second week of July. The report summarized the findings of the international investigating team: An epidemic of influenza was attributed to influenza A/Panama/2007/97-like (H3N2) viruses that impacted the populations of the highlands region of Fianarantsoa Province. This is the same strain that was associated with influenza epidemics worldwide during 2001-2002. The observed increase in excess mortality compared to previous years appeared to be due to widespread transmission and not an especially virulent influenza strain. Additional details are available in the WHO's report.
WHO report: <http://www.who.int/disease-outbreak-news/n2002/august/30august2002.html>
Elsewhere, during week 35, WHO reported that outbreaks of influenza were continuing to be detected in Argentina and Brazil, affecting mostly children. Influenza activity continued to be sporadic in Hong Kong SAR of China with predominantly A(H3N2) virus being detected.
WHO FluNet surveillance: <http://www.who.int/globalatlas/default.asp>

Total number of influenza tests performed and number of positive tests by province/territory of testing laboratory, Canada, 2002-2003

Specimens from NT, YT, and NU are sent to reference laboratories in other provinces.

Note: Cumulative data include updates to previous weeks; due to reporting delays, the sum of weekly report totals does not add up to cumulative totals.

Abbreviations: Newfoundland/Labrador (NL), Prince Edward Island (PE), New Brunswick (NB), Nova Scotia (NS), Quebec (QC), Ontario (ON), Manitoba (MB), Saskatchewan (SK), Alberta (AB), British Columbia (BC), Yukon (YT), Northwest Territories (NT), Nunavut (NU)

Respiratory virus laboratory detections in Canada, by geographic regions, are available weekly on the following website:
<http://www.phac-aspc.gc.ca/bid-bmi/dsd-dsm/rvdi-divr/>

Influenza tests reported and percentage of tests positive, Canada, by report week, 2002-2003

Percent positive influenza tests, compared to other respiratory viruses by reporting week, Canada, 2002-2003

Influenza strain characterization, Canada, cumulative, 2002-2003 influenza season by the Respiratory Viruses Section at the National Microbiology Laboratory
[n=0]

No new identifications for 2002-2003 season

(surveillance period August 25, 2002 - August 23, 2003)

See FluWatch Report Weeks 33 and 34 for 2001-2002 season strains (n=571)

Components of the 2002-2003 Canadian vaccine: A/New Caledonia/20/99 (H1N1)-like virus, A/Panama/2007/99 (H3N2)-like virus and B/Hong Kong/330/2001-like virus.

Please note that the above graphs may change as late returns come in.

Definitions for the 2002-2003 season

[FluWatch]