I was surprised to see the death rate for swine flu is not much different from the regular seasonal flu (according to the stats given). wow! the avian flu is i

I was surprised to see the death rate for swine flu is not much different from the regular seasonal flu (according to the stats given). wow! the avian flu is incredibly lethal, but I guess it kills its host before it can infect many others. I wonder what is the most dangerous intermediate death rate that maximizes damage by spreading to a wide population and killing many. Any computational biology geeks reading HN who know the answer?