Ebola misinformation is the biggest challenge: USAID The Director of USAID's Office of US Foreign Disaster Assistance (OFDA) says that the lack of public understanding surrounding the transmission of Ebola is one of the biggest challenges public health officials face in dealing with the epidemic. Sixteen tonnes of medical equipment donated by the US government arrived on Sunday in Liberia, which has seen the highest death toll of the West African countries affected. IMAGES AND SOUNDBITES.