Senegal has closed its land border with Guinea to try to prevent the spread of the Ebola virus, which Guinean authorities suspect of killing 70 people in the deadliest outbreak in seven years.
The discovery of 11 people suspected to have died of Ebola in Sierra Leone and Liberia in recent days has stirred concern that one of the most lethal infectious diseases known to man could spread in a poor corner of West Africa, where health systems are ill-equipped to cope.
Senegal's interior ministry said it had closed the land border with Guinea in the southern region of Kolda and the southeastern region of Kedougou.
Senegalese authorities said on Friday they would introduce sanitary checks on flights between Dakar and the Guinean capital Conakry, where eight cases of Ebola have been confirmed, including one death. West African foreign ministers said at a conference in Ivory Coast last week that the outbreak was a "threat to regional security".
There is no vaccine and no known cure for the disease, which can cause vomiting, diarrhoea and external bleeding that carry the virus outside victims' bodies and threaten to infect anyone who touches them.
Ebola has killed more than 1,500 people since it was first recorded in 1976 in Congo, but this is the first fatal outbreak in West Africa.