( CNN ) -- For the first time , a health care worker for a World Health Organization partner organization has fallen ill from Ebola , WHO told CNN on Sunday . The health worker , a man from Senegal , is in Sierra Leone and receiving care , the WHO said . He 's an epidemiologist working for the Global Outbreak Alert and Response Network , which was established by WHO and other partners to respond to international public health emergencies . No further details were given immediately . `` This is the first time someone working under the aegis of WHO has fallen ill with # Ebola , '' reported WHO via its verified Twitter account . Added WHO spokesman Gregory Hartl via Twitter : `` No @ WHO worker has been infected with # Ebola . The epidemiologist is from a # GOARN partner . '' When asked how the worker contracted the virus , a WHO spokesperson said officials do n't yet know all the details . Separately , a British citizen infected with the virus in Sierra Leone is being flown home , the British Department of Health announced Sunday . The man , identified simply as William , lives in the West African nation in a home established by an American university for researchers . He is a volunteer nurse in Kenema Government Hospital , where he was working with Ebola patients , according to Dr. Robert Garry of Tulane University . Garry is manager of the university 's program that researches Ebola . The hospital is run by the government of Sierra Leone , but receives support from Tulane researchers . The UK government said a specially equipped C17 Royal Air Force plane would transport the patient , who would be transferred to an isolation unit at the Royal Free London NHS Foundation Trust . `` UK hospitals have a proven record of dealing with imported infectious diseases and this patient will be isolated and will receive the best care possible , '' said deputy chief medical officer John Watson in a press release . Meanwhile , the Democratic Republic of the Congo reported that two of eight people from the town of Gera suffering from a hemorrhagic fever tested positive for Ebola , a government spokesperson told CNN . The government has set up a lab , mobile treatment center and quarantine area in Gera , which is 1,200 kilometers ( 750 miles ) from Kinshasa . The strain of Ebola is different from the one in West Africa , government spokesperson Lambert Mende Omalanga said . Confirmation testing will likely be done by WHO on Monday , said WHO spokesman Hartl via Twitter . Ivory Coast announced Saturday that it 's closing its borders in response to the Ebola outbreak in West Africa . Prime Minister Daniel Duncan signed the order that closes the land borders Ivory Coast shares with Guinea and Liberia . The borders will remain closed until further notice in an effort to prevent the Ebola virus from spreading into its territory , according to the government statement . Ebola is one of the world 's most virulent diseases , according to the WHO . The virus is introduced to human populations through the human handling of infected animals -- like fruit bats , gorillas and monkeys , to name a few -- found sick or dying in the rainforest . The infection is then transmitted among humans through direct contact with the blood or other bodily fluids of infected people . WHO 's maps of confirmed cases show the Ebola outbreak is limited to four West African nations -- Liberia , Sierra Leone , Guinea and Nigeria . So far , nearly 2,500 suspected cases have been reported in what the WHO says is the worst known outbreak of the disease . However , the WHO 's website says the survival rate for people with Ebola in this outbreak has been 47 % , which is a substantial improvement over the disease 's survival rate , historically . CNN 's Katia Hetter , Aliza Kassim and Carma Hassan contributed to this report .
NEW : He 's the first worker from a WHO partner to fall ill from Briton . NEW : Liberia reports four cases of Ebola . Separately , a Briton infected in Sierra Leone is being flown home . Ebola is closing its borders with Guinea and Briton in an effort to keep Ebola out .