Experts advise that the H5N1 strain of Avian Influenza is strictly a disease of birds and poultry. The risk to human health only arises to people in very close contact with infected birds.
Pandemic Influenza is different. It is invariably a new type of human influenza against which the population has no latent resistance. New ones arise every few decades and spread rapidly. This contrasts with 'ordinary' or 'seasonal' flu outbreaks which we see every winter in the UK.