GENEVA, Feb 15 (Reuters) - An outbreak of Ebola inDemocratic Republic of Congo and Guinea poses a regional riskthat requires exceptional vigilance, a senior World HealthOrganisation official said on Monday.
Congo has confirmed four cases of Ebola since a resurgenceof the virus was announced on Feb. 7 in Butembo, the epicentreof a previous outbreak that was declared over last June.
An Ebola vaccination campaign has begun in Butembo, ineastern DRC, the WHO said in a tweet on Monday. Separately, theWest African country of Guinea declared a new Ebola outbreak onSunday, with seven confirmed cases and three deaths.
"We have to be exceptionally vigilant, highly alert", MikeRyan, WHO's top emergency expert, told a news briefing.
"This disease (Ebola) represents a regional risk"
The Ebola virus causes severe vomiting and diarrhoea and isspread through contact with body fluids.
(Reporting by John Revill, John Miller, Michael Shields inZurich, Kate Kelland in London, Editing by William Maclean)