[imacomputer2]

Great article. Isn't it obviously that Ebola or any other deadly virus is unlikely to become highly contagious via air simply because we don't see mass airbourn infections very often. (Do we ever see them?) If such mutations were likely, then we would see them. Massive plagues, wiping out something like %50 of the population would be common. There have been mass plagues in history of course, however, they are somewhat rare and often the result of poor sanitation. That's not as much of a problem in the modern world, although the third world still struggles with it. Worse yet, if airborn mutations were likely, then we would probably not see them at all, because evolution would not have brought about highly complex creatures. We would always get killed off by disease before making that far.

[nyan_sandwich]

The flaw in this is that our mobility and density is unprecedented, so things that were not feasible for a startup plague in the past may now be feasible.

[TheSpiceIsLife]

There are selection pressures against infections that kill the host. That may explain why highly quickly-lethal viruses are rare.

[rectangletangle]

This is generally true, though occasionally parasitoid relationships are selected for (where there's a fitness advantage to killing off the host). Though these relationships typically only occur with an r selected host (many offspring, low probability of survival). Thankfully however humans are very heavily K selected (few offspring, high probability of survival).

[Havoc]

>>we don't see mass airbourn infections very often.

Flu?

[TheOtherHobbes]

Common cold, also. Rhinoviruses aren't exactly rare.