An American doctor who fell sick in Liberia with Ebola after treating people infected in a West African epidemic was in stable condition Sunday, his aid agency said.
Samaritan's Purse, a Christian charity, said Dr Kent Brantly had been isolated at the group's Ebola treatment center at the ELWA hospital in the Liberian capital Monrovia.
"We remain optimistic for his recovery, but certainly he is not out of the woods," said spokeswoman Melissa Strickland.
His symptoms include intermittent fever and body aches.
In a statement announcing the Ebola case Saturday, the organization said that Brantly was married with two children.
"Samaritan's Purse is committed to doing everything possible to help Dr Brantly during this time of crisis. We ask everyone to please pray for him and his family," it added.
The US State Department said it was aware of an Ebola case but could not provide information about a private individual.
Brantly is the medical director of the Samaritan's Purse Ebola case management center in Liberia, where the agency continues to work with Liberian and international health officials to contain the outbreak.
He began work with the group's Liberia team in October and had focused on Ebola patients since June.
Ebola is a hemorrhagic fever with a very high fatality rate. Liberia, Sierra Leone and Guinea have borne the brunt of the recent epidemic, and last week Nigeria recorded its first death.
As of July 20, the number of Ebola cases recorded in the months-long epidemic stood at 1,093, including more than 660 deaths, according to the World Health Organization.
The virus can fell victims within days, causing severe fever and muscle pain, vomiting, diarrhea and, in some cases, organ failure and unstoppable bleeding.
Ebola is believed to be carried by animals hunted for meat, notably bats. It spreads among humans via bodily fluids including sweat, meaning you can get sick from touching an infected person.
With no vaccine, patients believed to have caught the virus must be isolated to prevent further contagion.
Ebola first emerged in 1976 in what is now the Democratic Republic of Congo, and is named after a river there.