UNITED NATIONS, Nov. 25 -- The World Health Organization (WHO) on Tuesday warned of missing Ebola response targets in some areas of West Africa amid two new confirmed cases in Mali.

"The identification of patient contacts for daily monitoring has reportedly reached 99 percent," the UN health agency said in a press release. "Based on experiences in Senegal and Nigeria, this achievement could augur well for rapid containment of Mali's outbreak."

Sierra Leone, Liberia and Guinea are the three hardest hit countries in the Ebola outbreak in West Africa. Senegal and Nigeria, which had been affected, are now Ebola-free. Mali, previously free from the virus, is the latest country to register Ebola cases.

To date, WHO has reported 15,351 Ebola cases in eight countries since the outbreak began, with 5,459 reported deaths, mostly in Sierra Leone, Liberia and Guinea.

"Most of these patients had symptom onset in early to mid- November, indicating ongoing chains of transmission," said the WHO press release, while confirming two new cases, bringing to eight the total reported cases in Mali.

"With WHO support, staff from Mali's Ministry of Health will be meeting with health officials from Guinea to discuss cross-border measures for coordinating control efforts and reducing the likelihood that additional cases will be imported from Guinea into Mali," WHO said.

The United Nations, as part of its intensified support to both the preparedness and response efforts of the Malian government, will be opening on Wednesday an office of the UN Mission for Ebola Emergency Response (UNMEER) in Bamako, the capital.

UNMEER's Guinea office, meanwhile, reported that community reticence in many areas remains the main obstacle to contact tracing. Ebola is spreading in the north up to the border with Mali, an area with no functioning treatment centers or transit centers.

In response to a question at the UN press briefing in Geneva, WHO spokesman Tarik Jasarevic said the Dec. 1 targets for treatment and burials and set by his organization in its response to Ebola would likely be reached in many places, but not in others.

UNMEER head Anthony Banbury had said in media interviews that the mission is already exceeding its Dec. 1 targets in some areas, but that it is almost certain the targets will not be reached in all areas.

The targets are the so-called "70-70-60 plan", which aims to try to get 70 percent of the cases isolated and treated, and 70 percent of the deceased safely buried within 60 days from the beginning of October to Dec. 1.

UNMEER also reported that 150 health workers from the West African countries of from Benin, Ghana, Ivory Coast, Mali, Niger and Nigeria will be trained in Accra, Ghana this week to help tackle Ebola in Guinea, Liberia and Sierra Leone.

In Liberia, UNMEER said, it plans have two or three of its helicopters positioned in Monrovia by next week to ensure immediate dispatch of teams and supplies to any outbreak.

And as of Tuesday, according to the UN Office for the Coordination of Humanitarian Affairs (OCHA), 807.5 million dollars of the 1.5-billion-dollar Ebola response plan for West Africa was funded, which represented 54 percent of the appeal met.

Meanwhile, the UN Global Compact will convene an event in New York on Dec. 11 in cooperation with the Ebola Private Sector Mobilization Group, a coalition of over 35 companies with major assets and operations in West Africa mobilizing business resources, to support front-line Ebola humanitarian relief efforts while also advocate for a more concerted global response to the outbreak and recovery, UN officials said.