Leaders from West African countries ravaged by an outbreak of Ebola have pleaded for more international aid. Speaking by video conference at a meeting of the World Bank, Sierra Leone President Ernest Bai Koroma said help was needed on the ground, not just on paper.

President Ernest Bai Koroma: “The last few weeks have indeed been weeks of massive concerns and commitments to fight the outbreak. However, the general international response has up to this moment been slower than the rate of transmission of the disease.”

Liberia has postponed next week’s Senate elections over fears they could fuel the virus’s spread, and a fourth doctor has died of Ebola there. A round of 100 U.S. marines have arrived in Liberia, bringing the total number of troops there to 300.