It's the worst Ebola outbreak in history. The virus is now being blamed for more than 700 deaths in four West African countries, and it shows no sign of coming under control.
Now U.S. health officials are warning Americans not to travel to the three hardest hit countries: Guinea, Liberia, and Sierra Leone.
"Unfortunately, these countries don't have the infrastructure to handle the response, and, moreover, they don't have any experience with these kind of outbreaks in the past," Dr. Steve Monroe, with the Centers for Disease Control and Prevention, said.
Meanwhile, American missionaries Nancy Writebol and Dr. Kent Brantly will be returning to the United States to be treated for Ebola.
They were serving on a joint team in Liberia with Samaritans's Purse and the Christian missions organization SIM when they contracted the virus.
Writebol is in stable but serious condition and is receiving an experimental drug.
"The Ebola virus in terms of mortality rate right now is at about 64 percent. That's good news for us. We feel mom has a chance," Jeremy Writebol, her son, said.
Franklin Graham, CEO of Samaritan's Purse, said Dr. Brantly is fighting for his life.
"It's a very difficult day for him. We just ask everybody who's watching, if they will pray," Graham said.
Those who know Dr. Brantly say he put his life on the line for one reason.
"This is a guy who thinks people should give more than lip service when they say they're going to follow Jesus," Kent Smith, from Southside Church of Christ, said.
Meanwhile, Liberian Christians are gathering for a time they are calling sackcloth and ashes, asking God to halt the spread of Ebola in their country.
Five-hundred leaders are coming together in the capital city of Monrovia for three days of fasting and prayer.
Pastor Emery David, with Triumphant Christian Church, told CBN News that Christians are trusting God for a miracle.
"What we want is this Ebola lifted. If it is an error, a sin that we have committed, we want God to forgive the Church, the government, the nation, and heal the land," he said.