The reasons for this debate are not to be
found in the strictly medical or biological aspects of the outbreak. In
this respect, it might be useful to recall a few facts. First of all, the
influenza was classified as new not because it is a type A outbreak,
or a H1N1 subtype e the well-known pandemic of influenza of 1918
was a type A/H1N1, and since the seventies this type of virus has
been detected in seasonal outbreaks;