The U.N. health agency may have decided way back in 1996 that the remaining stores of live smallpox virus--kept in facilities in Atlanta and Russia--be destroyed, but the virus has remained alive so researchers can examine it, creating vaccines and other cures. Now the U.S. has asked for the virus to stay extant for another five years for the same reason.
There will certainly be a long debate about this; many poorer countries, with less resources to treat a potential outbreak of a virus as destructive as smallpox, have long pleaded for the destruction of the remaining instances, for fear of it somehow escaping. But the U.S. and a few other countries would rather study it, and hopefully create a true cure. Several have been produced, with varying degrees of success, but the World Health Organization wants to keep working with (and against) the virus. The U.S. does not have the power to unilaterally decide the fate of smallpox, and the dispute is unlikely to be decided this year. So for now, it rejoins rinderpest in the freezer.
[SFGate]