Influenza assessment centres: a case study of pandemic preparedness to alleviate excess emergency department volume.

Objectives: Influenza assessment centres (IACs) were deployed to reduce emergency department (ED) volumes during the pH1N1 influenza outbreak in the Kingston, Frontenac, Lennox and Addington (KFL&A) public health region of Ontario, Canada, in the fall of 2009. We present a case study for the deployment of IACs to reduce ED visit volume during both periods of pandemic and seasonal communicable disease outbreak. Methods: An emergency department syndromic surveillance system was used to trigger the deployment of eight geographically distributed IACs and to time their staggered closure 3 weeks later. We compared actual and expected ED visit volumes in the KFL&A region to neighbouring regions where no IACs operated by time series regression analysis before, during, and after IAC operation. Results: The deployment of IACs was triggered with a rise in overall ED volume at the hospitals in the KFL&A region to a level 10% above the 6-month running average. The IACs assessed 2,284 patients during 3 weeks of operation. Thirtythree patients were admitted directly to the hospital from the IACs, bypassing the EDs. During the operation of the IACs, the hospitals in the KFL&A region experienced a modest decrease in daily visits when compared to the 3 previous weeks. Overall ED visit volume in the hospitals in the neighbouring regions increased 105% during the period of IAC operation. Conclusions: Operating stand-alone influenza IACs may reduce ED volumes during periods of increased demand, as observed during an anticipated pandemic situation.