There is a certain amount of false information regarding how infectious the Ebola virus is, see, for example, some of the statements by certain Congressman. Mathematical epidemiologists use something called “R naught”, the basic reproductive number, to quantify how many new cases arise, on average, from a given case. These can be thought of as new cases caused by infection between a sick individual and those who have had contact with that sick person.
The World Health Organization recently completed a study that found R naught to be around 1.7 (e.g. so a case on average gives rise to about 1.7 other cases). The challenge for infection control is to get R naught below the replacement rate, less than 1.0. In contrast, R naught for the flu is greater than 10. The Ebola virus is about 10 times less infectious than the flu.