Challenges for the laboratory before and during an influenza pandemic.

Laboratory tests that reliably confirm infection with a novel influenza strain are a major component of pandemic planning. Combined nose and throat swabs are the most practical respiratory tract sample to safely obtain from patients. As nucleic acid tests are sensitive, specific and rapid, they will be the diagnostic test of choice during a pandemic. Virus isolation (in laboratories with Physical Containment level 3 facilities) is required for characterisation of the pandemic strain and vaccine development. Antiviral resistance testing may be required if antiviral drugs are used extensively to help control a pandemic. Diagnostic strategies will vary throughout the various pandemic phases.