Around 30 such diseases have emerged during the past two decades or so notably Hanta virus and Ebola fever.

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Uganda's Ministry of Health declared the outbreak in Kibaale district Saturday after getting confirmatory results from the Uganda Virus Research Institute identifying the disease as Ebola hemorrhagic fever, Sudan strain.

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Dr Gerard said that although his department at Gatwick regularly screened immigrants and asylum seekers for TB that they had not so far encountered any of the rarer illnesses such as Ebola or Lassa Fever, but he said they were alert to the threat.

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This is Uganda's first attack of Ebola, though a related fever killed 19 people in the east of the country in 1977.

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At least 72 people died in an outbreak of fever similar to ebola in north-east Congo.

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It is an extremely rare and lethal haemorrhagic fever, closely related to Ebola, for which there is no known cure.

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And now comes an outbreak of the deadly Ebola virus, the contagious and incurable fever that makes its victims bleed to death through their ears, nose, throat, everywhere.

ECONOMIST: Uganda