The 1918 virus actually had a "small" death rate (I think around 5% of those infected died) while the current H5N1 virus' death rate may be higher. We currently have no immunity to H5N1 while in general the population does have some level of immunity to the 1918 virus, since the people it didn't kill went on to have children and passed on whatever genetic resistance we had to the virus. It is also possible, though I haven't looked it up, that less-nasty variants of the 1918 virus have been cirulating in the population ever since, thus allowing people to build up immunity to it.

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Now while I might be amused by Cthulhians, I don't necessarily distrust them to carry out the functions of government. -- JayUtah

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