LONDON (AP) — The World Health Organization's emergencies chief said the ongoing Ebola outbreak in Congo is approaching a "stark" milestone with nearly 2,000 people killed by the virus in the year-long epidemic.

In a press briefing on Friday, Dr. Mike Ryan said that although the U.N. health agency has the vaccines and drugs that could potentially change the course of the outbreak, delivering those to the people who need them is still proving problematic.

"Over the last couple of weeks, we've seen worrying extensions of the disease," Ryan said, noting that Ebola is continuing to affect new areas in Congo. He said one case in Pinga, northeast of Goma, had no known links to other cases.

Ryan said WHO is asking for another $278 million to support efforts to contain Ebola.