FluWatch report: August 28 to September 10, 2016 (weeks 35-36)

Laboratory Confirmed Influenza Detections

In week 35-36, the percentage of tests positive for influenza remained at interseasonal levels, ranging from 0.2% in week 35 to 0.7% in week 36. For data on other respiratory virus detections, see the Respiratory Virus Detections in Canada Report on the Public Health Agency of Canada (PHAC) website.

Nationally in weeks 35-36, there were 13 positive influenza tests reported. The detections of influenza A and B were approximately equal in weeks 35 and 36. The majority of regions across Canada reported no influenza detections. For more detailed weekly and cumulative influenza data, see the text descriptions for figures 2 and 3 or the Respiratory Virus Detections in Canada Report.

To date this season, detailed information on age and type/subtype has been received for less than five cases.

Syndromic/Influenza-like Illness Surveillance

Healthcare Professionals Sentinel Syndromic Surveillance

In week 36, 0.98% of visits to healthcare professionals were due to ILI.

Influenza Outbreak Surveillance

In weeks 35-36, no new laboratory confirmed influenza outbreaks were reported.

Provincial/Territorial Influenza Hospitalizations and Deaths

Sentinel Hospital Influenza Surveillance

Pediatric Influenza Hospitalizations and Deaths

Surveillance of laboratory-confirmed influenza associated pediatric (≤16 years of age) hospitalizations from the IMPACT network has not yet begun for the 2016-17 season.

Influenza Strain Characterizations

The National Microbiology Laboratory (NML) has not yet reported any influenza strain characterizations for the 2016-17 season.

Antiviral Resistance

The NML has not yet reported antiviral resistance results for influenza viruses collected during the 2016-17 season.

Provincial and International Influenza Reports

• World Health Organization influenza update
• World Health Organization FluNet
• WHO Influenza at the human-animal interface
• Centers for Disease Control and Prevention seasonal influenza report
• European Centre for Disease Prevention and Control - epidemiological data
• South Africa Influenza surveillance report
• New Zealand Public Health Surveillance
• Australia Influenza Report
• Pan-American Health Organization Influenza Situation Report

• Alberta Health - Influenza Surveillance Report
• BC - Centre for Disease Control (BCCDC) - Influenza Surveillance
• New Brunswick - Influenza Surveillance Reports
• Newfoundland and Labrador - Surveillance and Disease Reports
• Nova Scotia - Flu Information
• Public Health Ontario - Ontario Respiratory Pathogen Bulletin
• Quebec - Système de surveillance de la grippe
• Manitoba - Epidemiology and Surveillance - Influenza Reports
• Saskatchewan - influenza Reports
• PEI - Influenza Summary

FluWatch definitions for the 2016-2017 season

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).

Influenza-like-illness (ILI): Acute onset of respiratory illness with fever and cough and with one or more of the following - sore throat, arthralgia, myalgia, or prostration which is likely due to influenza. In children under 5, gastrointestinal symptoms may also be present. In patients under 5 or 65 and older, fever may not be prominent.

ILI/Influenza outbreaks

Schools:

Greater than 10% absenteeism (or absenteeism that is higher (e.g. >5-10%) than expected level as determined by school or public health authority) which is likely due to ILI.
Note: it is recommended that ILI school outbreaks be laboratory confirmed at the beginning of influenza season as it may be the first indication of community transmission in an area.

Hospitals and residential institutions:

two or more cases of ILI within a seven-day period, including at least one laboratory confirmed case. Institutional outbreaks should be reported within 24 hours of identification. Residential institutions include but not limited to long-term care facilities (LTCF) and prisons.

Workplace:

Greater than 10% absenteeism on any day which is most likely due to ILI.

Other settings:

two or more cases of ILI within a seven-day period, including at least one laboratory confirmed case; i.e. closed communities.

Note that reporting of outbreaks of influenza/ILI from different types of facilities differs between jurisdictions.

Influenza/ILI activity level

1 = No activity: no laboratory-confirmed influenza detections in the reporting week, however, sporadically occurring ILI may be reported

2 = Sporadic: sporadically occurring ILI and lab confirmed influenza detection(s) with no outbreaks detected within the influenza surveillance region ^{Footnote †}

3 = Localized:

1. evidence of increased ILI^{Footnote *} and
2. lab confirmed influenza detection(s) together with
3. outbreaks in schools, hospitals, residential institutions and/or other types of facilities occurring in less than 50% of the influenza surveillance region^{Footnote †}

4 = Widespread:

1. evidence of increased ILI^{Footnote *} and
2. lab confirmed influenza detection(s) together with
3. outbreaks in schools, hospitals, residential institutions and/or other types of facilities occurring in greater than or equal to 50% of the influenza surveillance region^{Footnote †}

Note: ILI data may be reported through sentinel physicians, emergency room visits or health line telephone calls.