And the only good thing that can be said about Ebola is there's a chance, and just a chance, that we'll look at how slow we moved and the decisions that were made and get better prepared because the chance of something that's more infectious than Ebola coming along is high enough that it would be very wise to be prepared. Such an aggressive and virulent threat would be short lived because if you isolate those infected, the virus soon runs out of hosts.
A "parasite" has to be careful not to kill the host.