I'm professor Hans Rosling.
I'm going to show you
why it is that the Ebola epidemic
is so dangerous.
It's because one patient, on average,
keeps infecting two other persons.
That doesn't sound so dangerous,
but I will show you
what it means in reality.
If this is the first person infected in the country,
that person will infect two others,
and this one will infect two others,
and this also.
Each of this ones infects two others.
That doesn't look too bad,
but look what happens when it continues.
There, it's already 32 persons infected.
If we let this continue,
the epidemic will become dangerous for the whole world.
Let me show you the danger in another way.
Look at the blocks.
Some diseases increase like this,
from month to month:
1, 2, 3, 4, 5, 6, 7.
That's not how Ebola increases.
If one patient infects two others,
it doubles from month to month,
so this is what it happens with Ebola:
1, 2, 4, 8, 16, 32.
And the next month, twice as many: 64!
So you see,
if actions are taken this month,
this is how much resources are needed.
If you delay the actions for another two months,
you'll need four times as much resources.
Not to mention if you delay it further.
There is no alternative:
the Ebola epidemic has to be stopped now.