United Nations Secretary General Ban Ki-moon announced Tuesday that the U.N. will convene a meeting of national leaders to discuss a response to the Ebola outbreak, amid reports predicting a significant increase in the number of people affected by the virus. The meeting is to be held at U.N. headquarters in New York on Thursday.

The meeting will also be attended by Alpha Condé, president of the Republic of Guinea, while Liberia’s President Ellen Johnson-Sirleaf and President Ernest Bai Koroma of the Republic of Sierra Leone, are set to join through teleconference, the U.N. said, in a statement Tuesday. Guinea, Liberia and Sierra Leone in West Africa have been hit the hardest by the worst outbreak of the virus, which has so far infected more than 5,800 people and killed more than 2,800. 

“This meeting will bring together global leaders to focus international attention to combat the outbreak of Ebola virus disease,” Ban said, in the statement, adding: “It aims to mobilize an exceptional response to contain and stop the spread of the virus, treat those who are infected, ensure essential services, preserve stability and prevent outbreaks in other countries.”

The meeting follows Tuesday's estimate by the World Health Organization that more than 20,000 people could be affected by November. The U.N. had earlier estimated that it will cost nearly $1 billion to tackle Ebola's spread, while the U.S. Centers for Disease Control and Prevention said that there could be nearly 1.4 million cases of Ebola by January if efforts to curb the spread of the disease are not enhanced.

Ban also announced the appointment of David Nabarro as the organization's Special Envoy for Ebola and Anthony Banbury as Special Representative and Head of the United Nations Mission for Ebola Emergency Response, in the statement.