A patient in hospital develops a fever and an acute infection of the upper respiratory tract. It is suspected that they may be suffering from infection with influenza A (H1N1), so a nasopharyngeal swab and a serum sample are taken.

The hospital laboratory can do ELISA, RT-PCR, viral culture, haemagglutination and haemagglutination-inhibition (HAI) tests, and has suitable reagents available to carry out all/any of these assays to identify and type the influenza virus.

Briefly discuss which of these tests are most suitable for detecting a current infection with influenza A. Explain why you would not use the other tests.

For the tests you choose to use, state which clinical sample you would use and why. Also, explain, which tests could distinguish the strain of virus and briefly, the basis of how the test is able to make this identificaiton