How long does it take for a pandemic virus to "die out"?

[The_Absolute]

How long does it usually take for a pandemic virus such as the swine flu to "die out"?

[MATLABdude]

Probably about as long as it takes those afflicted with the virus to die out. (No more hosts, no more virus--unless they can survive for a while outside of a host)

[jim mcnamara]

The Hong Kong virus was pandemic in 1957. This virus H3N2 close variants are still out there infecting human hosts.

http://en.wikipedia.org/wiki/H3N2

[byohannan]

Viruses dont die out at all completely naturally until their molecular structure is broken down . That is why it is recommened to burn the dead bodies of victims of virus pandemics like AIDS ,measles etc.

If not they will mutate themselves to cohabit in other animals mostly and make a reentry to humans eventually as another virus or to other species.