The Ebola virus and outbreak explained

WHAT IS EBOLA?

Ebola is a viral illness. Initial symptoms can include a sudden fever, intense weakness, muscle pain and a sore throat, according to the World Health Organisation (WHO). Subsequent stages are vomiting, diarrhoea and - in some cases - both internal and external bleeding.

WHEN DID THE OUTBREAK BEGIN?

In December 2013 in Guinea, but it was not detected until March 2014.

HOW MANY HAVE DIED?

A total of 2296 have died out of 4293 recorded Ebola cases in five West African countries, according to the WHO's latest report on September 6.

HOW DOES IT SPREAD?

It spreads between humans by direct contact with infected blood, bodily fluids or organs, or indirectly through contact with contaminated environments.

WHEN ARE PEOPLE CONTAGIOUS?

Ebola isn't contagious until symptoms appear. The incubation period - the time interval from infection with the virus to onset of symptoms - is two to 21 days.

IS THERE A VACCINE?

There is no licensed vaccine for Ebola available. This month scientists said they may have developed an effective vaccine for the Ebola virus after an experimental immunisation gave monkeys long-term protection from the deadly disease.

WHEN DID IT FIRST EMERGE?

Ebola first appeared in 1976 in two simultaneous outbreaks, in Nzara, Sudan, and in Yambuku, Democratic Republic of Congo. The latter was in a village situated near the Ebola River, from which the disease takes its name.

HOW WAS IT INTRODUCED TO HUMANS?

In Africa, infection has been documented through the handling of infected chimpanzees, gorillas, fruit bats, monkeys and forest antelope.