GENEVA, Sept 5 (Reuters) - More than 2,000 people have died in the Ebola outbreak in West Africa, the World Health Organization said on Friday, out of about 4,000 patients thought to have been infected in the three countries worst hit by the disease.

The death toll in Guinea, Liberia and Sierra Leone totalled 2,097 as at Sept 5, out of 3,944 cases, a WHO document said. The data did not include patients in Nigeria or Senegal, which have also been affected, nor Democratic Republic of Congo, which has been hit by an unrelated outbreak of the disease. (Reporting by Tom Miles, editing by Stephanie Nebehay)