Population growth, the cutting down of forests and increased mobility all contribute to the current crisis. "The virus hasn't changed," says one infectious disease expert. "Africa has changed."
A widely watched video shows a foreigner fainting on a subway car and everyone around him fleeing. No one helps. It's rekindled a national debate about trust, fear and the Chinese national character.
Food shortages are emerging in the wake of West Africa's Ebola epidemic. Market shelves are bare and fields are neglected because traders can't move and social gatherings are discouraged.
The hunt is on to identify the man in the James Foley execution video who speaks with a British accent. An estimated 2,000 Europeans have left home to join the Islamic State in Syria and Iraq.
The U.S. could aid moderate rebels. It could bomb militants of the Islamic State. Or it could sit on the sidelines as the war plays out. There are many choices, but none appears promising.
Dr. Joanne Liu of Doctors Without Borders says fear and a lack of sense of urgency has kept the international community in their home countries rather than stepping up to the plate in West Africa.
The WHO has called for donations to help contain the outbreak. But money is just the first step. The challenges run from finding the right staff to prepping neighboring countries just in case.
As the Ebola outbreak rages in West Africa, it is also unfolding — in a virtual sense — inside the computers of scientists trying to predict how far the outbreak will spread and when it will end.