Identification of pandemic viral strains. Role of the national reference centre.

The identification of a pandemic viral strain will be performed by the National Reference Centres. The well established sentinels network collecting respiratory samples is able to work not only during the winter season but also a part from it and to allow the early detection of new variants. It also supplies pertinent clinical and epidemiological data in order to correlate a new strain with authentic pathogenic and epidemiologic potential. Based on the previous pandemics experiences, and on the current circulating Influenza strains in humans and animals, a limited number of H and N antigens could be expected as component of a new pandemic strain. The recent rapid tests for the detection and the isolation of influenza viruses permit the diagnosis of a new strain within a few days or weeks. Rapid exchanges of data, strains and reagents under the WHO authority would help in a rapid prediction of a pandemic risk.