Influenza Surveillance In Saskatchewan Ken Brandt Manager, Virology Section Provincial Laboratory Regina, Saskatchewan

Purpose The early detection of Influenza A and B in the province The early detection of novel influenza strains in the province

Saskatchewan has had an influenza surveillance program for over thirty years Now part of Flu Watch – the Federal/Provincial influenza surveillance program

Saskatchewan’s program is unique - the Flu Watch program is run out of the Provincial Laboratory instead of being run by the provincial epidemiologist - we recruit our own surveillance physicians not NARES

Currently have 13 sentinel physicians that geographically cover all areas of the province They report influenza-like illness (ILI) on a weekly basis Requested to send 2 NPS specimens each week on patients they see with ILI

ILI definition for 2004 – 2005 Acute onset of respiratory illness with fever and cough and with one or more of the following – sore throat, arthralgia, myalgia, or prostration which could be due to influenza virus. In children under 5, gastrointestinal symptoms may also be present. In patients under 5 or 65 and older, fever may not be prominent.

Problems with ILI - sentinel physicians may not see any patients with ILI on their recording day - symptoms seen may not match ILI definition or the symptoms shown may be due to other viruses

For example: - 68 year old male presents with cough and nasal congestion - 15 year old male with fever, cough, sore throat and flu-like symptoms - 10 year old male with fever, cough, sore throat and nausea/vomiting Which one has influenza?

- 68 year old male presents with cough and nasal congestion = Influenza A - 15 year old male with fever, cough, sore throat and flu-like symptoms = Parainfluenza year old male with fever, cough, sore throat and nausea/vomiting = Adenovirus

Laboratory confirmed cases of influenza from the clinical specimens submitted to us are the main source of data that we use in Saskatchewan for Flu Watch - advantage over ILI is that you know exactly what you are dealing with

The number of clinical specimens received on a daily basis from all areas of the province provide a more accurate picture of respiratory virus activity in the province than weekly ILI data Direct correlation with the number of incoming specimens and influenza positives

Therefore, in reality, we do not just have 13 surveillance physicians but every physician submitting a specimen becomes a surveillance physician Because we routinely screen for influenza on all respiratory specimens no matter what month we are providing year round surveillance

Respiratory specimen protocol: - Direct DFA using Chemicon’s Simulfluor Respiratory screen – detects the presence of 7 respiratory viruses including Influenza A, Influenza B, Parainfluenza 1,2 and 3, RSV and Adenovirus - Tissue culture isolation (PMK, MDCK, HP2) - Molecular testing

HAI is done on all tissue culture positive Influenza A isolates to determine strain – i.e. H1N1 or H3N2 Critical - if the isolate is not H1N1 or H3N2 it is sent to our molecular lab for further testing as it may be a novel or pandemic strain

Additional data used to determine influenza activity in the province: - reports of school and work site absenteeism - confirmed outbreaks in hospitals, LTC facilities

In conclusion: - In Saskatchewan, influenza surveillance or Flu Watch is laboratory based - The main source of data for influenza activity is lab confirmed positive influenza tests

- other sources of data include number of incoming respiratory specimens, ILI data from surveillance physicians, reports of school and work site absenteeism and outbreaks - strain identification is critical in providing timely information for pandemic planning