This Author has previously Posted commentary basically stating: Pandemics are cheaper and easier to deal with, without previous Planning or Stockpiling of Drugs. Pandemics stretch the breath of physical animal health, and can potentially affect anything; even with introduction of viral mutation from Plant life. Identification of a primary source of a Pandemic even fails, because of the potential directional spread of the mutation--which can seriously alter for every animal entity the infection might enter. The rate of mutation also defeats, as it can occur within minutes, or require decades. No Designed Drug will ever deal precisely with the ailment for which it was designed to counter.
There is almost no potential for a universal Immunization therapy. No Anti-viral or Anti-Bacterial drug is 100% effective in eradicating an undesirable infection. The residue survival stands a the main source of mutation, where the most-resistant strain of infection survives. The only true source for human salvation is the development of successful antibodies in the human structure, these developed by infection survivors and their progeny. The danger of any Flu strain will not attain the danger levels existent in WWI because of the intervening development of antibodies (not even the Bird flu), but it is entirely possible more People will suffer longer and worse bouts of flu than ever before, with a huge Pricetag attached.
There is little major threat from the Bird flu, which probably could not even cause the Death rate per Ten Thousand caused by the Flu in the 1950s. This is not to say We could not have half the World sicker than they have ever been before at a huge Cost. lgl