Found in a textbook today (, p. 14-15), immediately following a discussion of Ebola and Lassa fever infections in humans:
While having the death of a host individual occur as the product of an encounter with a pathogen may seem like a dire outcome, this outcome represents a mechanism of defence operating at the leve l of the host population. If a particular infectious agent is something against which members of the host population could not easily defend themselves, then it may be better to have that particular host individual die (and die very quickly!) to reduce the possible spread of the contagion to other members of the population.
In other words, if it looks like you’ve been infected by something nasty, you sacrifice yourself to stop its spread for the good of the other members of your population.
Look, I’ll be the first to admit that I hold a dim view of multi-level selection, but I’d be really surprised if anyone in the MLS camp were to make an argument as simple-minded as this. Virulence is a complex topic, certainly, but the above paragraph could have been lifted from a previously-unknown book by Wynne-Edwards in the 1960s and no one would know the difference. How is it that people are still getting away with stuff like this forty years after it was first shredded by the likes of George Williams and John Maynard Smith?