WEST African nations neighbouring those hit by the Ebola epidemic - Mali, Ivory Coast, Senegal and Guinea Bissau - should prepare for the possible arrival of travellers carrying the deadly virus, the World Health Organisation (WHO) has warned.

"We want other countries in West Africa to be ready - bordering countries, Ivory Coast, Mali, Senegal, Guinea Bissau - to prepare themselves in case people affected with the disease may be also travelling," WHO medical officer Dr Pierre Formenty told a briefing in Geneva.

Despite efforts by national health authorities and aid organisations to contain the spread of Ebola, the WHO has recorded 635 infections, including 399 deaths, in Guinea, Sierra Leone and Liberia since the outbreak began in February.

Loading article content

It is already the deadliest since Ebola first emerged in central Africa in 1976, and the number of infections continues to rise.

Dr Formenty said it was difficult to stop the spread of the virus in forested areas of the three countries already affected.