The death toll from the West African Ebola outbreak has climbed to 518.
The World Health Organization says 37 deaths attributed to Ebola were reported late last week in Guinea, Liberia, and Sierra Leone, the three countries where the disease has been confirmed.
A suspected Ebola patient in Ghana tested negative, but Ghanaian news sources say the man -- a U.S. citizen -- has since died for undetermined reasons.
The WHO says the total number of Ebola cases in West Africa stands at 844. It notes there have been no new cases in Guinea, formerly the center of the outbreak.
The U.N. agency reports 16 new cases in Liberia and 34 in Sierra Leone.
Regional efforts to halt the spread of the disease have been hampered by traditional practices, such as home-based care and families personally burying their dead.
The often-fatal disease is spread between humans by direct contact with the blood or other bodily fluids from an infected person.
There is no specific treatment or vaccine for the Ebola virus. Before this year, the deadliest outbreak was in 1976 in the Democratic Republic of Congo, where 280 people died.