Tests conducted by a national lab in Uganda and confirmed by the US Centers for Disease Control indicate that the virus belongs to a different subtype than the four already known, said WHO spokesman Gregory Hartl.
Dr Sam Zaramba, director general of Uganda's health service, said Thursday that laboratory tests in South Africa and the United States confirmed 51 Ebola cases, and of those 16 patients died.
The first case was reported on 10 November in Bundibugyo district, 350 kilometers (200 miles) west of the capital, Kampala, but the cause was not immediately confirmed, Zaramba said.
Ebola typically kills most of those it strikes through massive blood loss, and has no cure or treatment. It is spread through direct contact with the blood or secretions of an infected person, or objects that have been contaminated with infected secretions.
Uganda last had an outbreak of Ebola in October 2000 when 173 people died and a total of 426 people were diagnosed with Ebola in northern Uganda.
In neighboring Congo, WHO and Congolese officials said last week an Ebola outbreak that killed six people had been contained.
The World Health Organization says more than 1 000 people have died of Ebola since the virus was first identified in 1976 in Sudan and Congo. Primates, hunted by many central Africans for food, can carry the virus. - (Sapa)
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