Even if they strongly suspected it will become airborne (based on something other than theory), do you think they'd just announce it to the public like "oh, hey, btw..."? Can you imagine the hysteria that would cause? Not "a bit" like another poster suggested. The effect of the hysteria could very well be worse than what the virus might cause on its own. It's really impossible to know, that is why we take measures to prevent getting worked into a highly irrational hysteria. These measures would include things like listening to qualified individuals and not ignoring the rational points they are trying to make to you.