Let's be sarcastic a little as I have to say that a death rate equal to that of the black death (33% casualties worldwide) would ease things a bit.
On the down side and the first one is a big one:
- It would have a good chance to knock at your door.
- Food supply disruption because of worker casualties.
- Fair increase in violence from panicking and paranoied people.
- Increase in war risk just because we are more stupid than pigs (much more).
On the bright side:
- Reduction of population need for goods.
- Reduction of food requirement worldwide.
- No more economical crisis as this would be the least of our problems.
- Reduction of global warming (less industry and reduced number of people farting).
- Reduction in the need for elder care as elders should be the first to die (further reduction of global warming).
OK, I stop. It can remind us of the avian flu and there is no reason to be scared yet. Anyway, from what I know, most of our diseases are coming from domestic animals. As we have to do with them we have to do with it.