Deadly Ebola virus reaches Nigeria as West Africa death toll hits 660

An Ebola outbreak that has left more than 660 people dead across West Africa has spread to the continent's most populous nation after a Liberian man with a high fever vomited aboard a flight to Nigeria and then died there.

The 40-year-old man had recently lost his sister to Ebola in Liberia, health officials there said. It was not immediately clear how he managed to board a flight, but he was moved into an isolation ward upon arrival in Lagos on Tuesday and died on Friday.

Nigerian Health Minister Onyebuchi Chukwu said it was the first case of Ebola to be confirmed in Nigeria since the current outbreak emerged this year. The disease has already hit Guinea, Liberia and Sierra Leone.

"All ports of entry into Nigeria, including airports, seaports and land borders, are placed on red alert," he said. "Ministry of Health specialists have been positioned in all entry points. Active surveillance has also been stepped up."

Authorities were investigating anyone who might have come into contact with the deceased, Chukwu said.