Giordano excpt what you are saying about how it is spreading is NOT born out by the facts. While I don't think there is evidence of regular spread by air, there IS lots of evidence of spread through very casual contact. Norovirus does not spread by air... but we all know how easily and fast that virus spreads.
This is why this important. If the current rate of spread contenues there will hundreds of thousands of cases by December and will will be in the millions of caes in the first half of next year. Even if it stays in Africa there is still the potential of millions of deaths.
With several hundred thousand cases by December do you really think they can keep it in africa?
Every month you wait to act... the estimated cost of containing this grows by tenfold. We might already be too late, I pray we are not.