The current Ebola outbreak is by far the worst the world has yet experienced. So far more than 930 people have died in West Africa, while more than 1,700 cases have been reported. The previous worst death toll came in 1976, when 280 people died in Congo and Zaire.
The mortality rate this time appears to be about 55%, though it can reach 90%. The World Health Organisation has now declared an international health emergency, but it is not proposing any bans on trade or travel.
Ebola is a fearsome disease, with symptoms that include high fever, internal and external bleeding, and damage to the central nervous system. There is no vaccine and no cure.
One of the obstacles to containing its spread is the poor state of the health services in the countries it has struck, with a lack of medical staff, laboratory technicians and protective clothing for doctors and nurses. (See also my blogs of April 4 and June 7.)