[Influenza: waiting for pandemic].

Pandemic flu is a sudden invasive infection, caused by the diffusion to humans of a viral strain characterized by the presence of one or more new surface proteins. Pandemic influenza prevention is among health priorities for WHO, that introduced a world surveillance programme and published Guidelines for preparing national pandemic plans. Following Guidelines, Italy prepared a plan considering human and veterinary health activities, among which the use of vaccines and antiviral drugs, and informative and formative projects.