From The Wall Street Journal:

Ebola outbreaks in several West African nations forced two heads of state to pull out of a historic Africa summit with President Barack Obama, in a reminder of how crises on the continent can undermine efforts to change U.S. perceptions of it. Ellen Johnson Sirleaf, the Nobel Peace Prize-winning president of Liberia, will stay home to deal with an Ebola epidemic that has killed more than 729 people, her office said. So will Ernest Bai Koroma, president of Sierra Leone.