The BBC has a good article on the numbers of people involved with the Ebola outbreak:
Ebola: Mapping the outbreak
The Ebola outbreak in West Africa was first reported in March 2014, and has rapidly become the deadliest occurrence of the disease since its discovery in 1976.
In fact, the current epidemic sweeping across the region has now killed more than all other known Ebola outbreaks combined.
Up to 12 October, 4,493 people had been reported as having died from the disease in five countries; Liberia, Guinea, Sierra Leone, Nigeria and the United States. The total number of reported cases is in excess of 8,900.
The World Health Organisation (WHO) admits the figures are underestimates and warns there could be as many as 20,000 cases by November if efforts to tackle the outbreak are not stepped up.
There are several graphs but this one really sticks out:
That is an exponential curve - really demonstrates that the R0 number is at least two. We need to quarantine the area immediately, not let people fly into the USA.