Data Collection
The Ontario Agency for Health Protection and Promotion (OAHPP) Laboratory (Toronto) performed the majority of pHlNl testing in Ontario; 84% of pHlNl cases detected during the first wave (April 19, 2009 August 29, 2009) were tested at OAHPP and 69% in the second wave (August 30, 2009 January 31, 2010). All respiratory specimens submitted to OAHPP laboratories were tested. Specimens were initially tested using a combination of endpoint reverse transcriptase (RT) polymerase chain reaction (PCR) for the influenza A virus matrix gene and sequencing. Specimens submitted after May 15, 2009 were tested using a more sensitive real time RT PCR for the pHlNl (H and N genes) developed at the Toronto laboratory. The Luminex Respiratory Virus Panel multiplex assay and viral culture were used to test approximately 6% of specimens [6].