To develop these estimates, researchers used a computer model that tracks the frequency of international traffic to different countries, the progression of the disease in already affected countries, and the incubation time and other aspects of Ebola. The estimates will be updated as the epidemic continues.
Outside of Africa, the risk is relatively high in the UK and France, but thankfully very low in India and China. The more advanced health-care systems in the UK and France are much better equipped to deal with an Ebola outbreak, while less advanced systems in China and particularly India, which also have considerably bigger populations to manage, could struggle to deal with an epidemic.
Peter Piot, who helped discover and name the virus, told the Guardian about his concerns with an outbreak in India:
But an outbreak in Europe or North America would quickly be brought under control. I am more worried about the many people from India who work in trade or industry in west Africa. It would only take one of them to become infected, travel to India to visit relatives during the virus's incubation period, and then, once he becomes sick, go to a public hospital there. Doctors and nurses in India, too, often don't wear protective gloves. They would immediately become infected and spread the virus.
As Vox's Julia Belluz previously explained, this is one of the nightmare Ebola scenarios that keeps scientists up at night. It's good, then, that the chance of Ebola spreading to India and China seems fairly remote.