"We must gear up for a serious epidemic, even though we hope it won't happen," Nigel Fisher, the United Nations humanitarian coordinator in Haiti, told Reuters.

More than 3,000 cholera cases have been reported so far in the poor, earthquake-hit Caribbean nation, which is experiencing its second humanitarian crisis since a catastrophic earthquake on January 12.

The U.N., Haiti's government and aid partners have launched a major effort to try to contain the epidemic.

This involved setting up cholera treatment centers to isolate patients in the two worst affected central provinces, Artibonite and Center, and in the capital Port-au-Prince. The main outbreak areas straddle the Artibonite River watershed, suspected of being the main propagator of the deadly disease.

Reuters