1.4 million people may be infected with Ebola by January, US warns

The number of Ebola infections in Liberia and Sierra Leone could skyrocket to 1.4 million by January, according to a worst-case scenario released by US health authorities.

The US Centres for Disease Control and Prevention estimated that Ebola cases in these two West African nations could range between 550,000 and 1.4 million cases by January 20.

The Ebola epidemic has killed 2,811 people of the 5,864 infected since the beginning of the year in Sierra Leone, Guinea, Liberia and Nigeria, according to the World Health Organisation.

The CDC estimate is based on the assumption that Ebola cases in the world's largest outbreak of the disease to date are being underreported by a factor of 2.5.

However, experts warned the figures were based on data that is three weeks old, before the US and other nations ramped up their responses to the epidemic.

Asked by reporters why the CDC would release information that was already out of date, the agency's chief, Tom Frieden, said the model was designed to be used by government leaders and international relief groups to model what might happen under different variables.