U.S. doctor battling Ebola takes slight turn for worse

Handout photo of Dr. Kent Brantly speaking with colleagues at the case management center on the campus of ELWA Hospital in Monrovia
Dr. Kent Brantly (R) speaks with colleagues at the case management center on the campus of ELWA Hospital in Monrovia, Liberia in this undated handout photograph courtesy of Samaritan's Purse. Brantly contracted Ebola and has been described as stable but suffering from some symptoms of the contagious disease, for which there is no known cure. REUTERS/Samaritan's Purse/Handout via Reuters (LIBERIA - Tags: HEALTH DISASTER TPX IMAGES OF THE DAY) ATTENTION EDITORS - THIS PICTURE WAS PROVIDED BY A THIRD PARTY. REUTERS IS UNABLE TO INDEPENDENTLY VERIFY THE AUTHENTICITY, CONTENT, LOCATION OR DATE OF THIS IMAGE. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. NO SALES. NO ARCHIVES

WINSTON-SALEM N.C. (Reuters) - The health of a U.S. doctor who contracted Ebola in Liberia while helping fight an unprecedented outbreak of the deadly disease has worsened slightly, a relief organization said on Thursday.

Dr. Kent Brantly and Nancy Writebol, an American missionary also infected with the virus, both are in "stable but grave condition," according to Samaritan's Purse, a North Carolina-based Christian relief group.

The organization, led by evangelist Franklin Graham, said it was aiming to have all nonessential personnel evacuated from Liberia by this weekend as conditions worsened. None of the staff leaving are ill, the group said.

On Wednesday, the U.S. Peace Corps said it was pulling all 340 volunteers from Liberia, Sierra Leone and Guinea because of the spreading Ebola virus.

The outbreak of Ebola in West Africa has killed 729 people out of 1,323 infected since February, the World Health Organization said on Thursday.

There is no known cure for the disease, but Graham gave some details about treatments the American workers have received in Liberia.

“Yesterday, an experimental serum arrived in the country, but there was only enough for one person. Dr. Brantly asked that it be given to Nancy Writebol,” Graham said in a statement.

“However, Dr. Brantly received a unit of blood from a 14-year-old boy who had survived Ebola because of Dr. Brantly’s care," Graham added. "The young boy and his family wanted to be able to help the doctor who saved his life.”

Dr. Kent Brantly and missionary Nancy Writebol were part of a team in Liberia from two North Carolina-based Christian relief groups, Samaritan's Purse and SIM.

(Reporting by Colleen Jenkins; Editing by Diane Craft)