WHO says Ebola outbreak in West Africa one of "most challenging"

The World Health Organization raised concerns Tuesday about the latest Ebola outbreak in West Africa and anticipates it will take two to four months to contain.

Keiji Fukuda, assistant director general of the U.N. agency, told reporters, "This is one of the most challenging Ebola outbreaks that we have ever faced."

The death toll topped 110 among suspected carriers of the virus that triggers an acute severe illness with symptoms including fever, headache, vomiting and diarrhea. While the fatality rate is high, up to 90 percent, no specific treatment and vaccine is available, according to the WHO.

WHO said 101 of Ebola patients died in Guinea and 10 in Liberia and it is conducting investigations in Sierra Leone, Ghana and Mali for possible outbreaks.