Surveillance Activities during Pandemic Phases Anne-Luise Winter APHEO-COMOH Workshop Toronto February 1, 2007

2 Objectives of Pandemic surveillance To detect early the entry of the Pandemic strain in Ontario To rapidly determine circulating strains in Ontario To provide data on circulating influenza strains To monitor activity and patterns of distribution of ILI To estimate the impact of the Pandemic To describe affected population/s, mode/s of transmission, risk factors To detect unusual events To track occurrence, severity, and progression by WHO/PHAC phase

3 Interpandemic Phases No new influenza virus subtypes detected in humans  A circulating animal influenza virus subtype poses a substantial risk of human disease Surveillance: Routine influenza surveillance Communication of phase progression

4 Pandemic alert phases Human infection/s with a new subtype. Rare  limited  larger cluster/s of human to human spread Surveillance Layered progression of activities Detection of the novel strain, heightened surveillance for detection of any unusual cases/clusters (e.g. FRI/SRI surveillance) done through strain characterization of ~ 10% of all isolates plus atypical cases, their close contacts with ILI and unusual outbreaks Continue with heightened surveillance until no longer sustainable  aggregate reporting Ongoing review of case definition Ongoing evaluation of epidemiology of novel strain

5 Interpandemic (seasonal) surveillance components

6 Pandemic Increased and sustained transmission in general population Surveillance: Utilization of pandemic reporting tools, various data collection systems (portal for aggregate data + secure platform for case level data) Case-level information collected on a small proportion of cases Assessment centres/hospitals/LTCHs for aggregate and case level data Monitor uptake, efficacy, adverse events associated with vaccines and antivirals Ongoing evaluation of epidemiology, to direct priorities to high-risk group/s Diagnosis by clinical, not lab, criteria Prioritization of laboratory testing

7 Postpandemic Period Recovery/Resolution Surveillance: Estimate burden of disease Evaluate surveillance systems Eventual resumption of interpandemic activities, scaling down pandemic surveillance as appropriate

8 Questions? Anne-Luise Winter: (416)