At least 10,000 people suffering from cholera are in hospitals across the country.

Doctors in Port-au-Prince say they are alarmed at the speed at which new cases are emerging.

A senior health ministry official said the epidemic was now "a matter of national security".

The ministry on November 10 confirmed the disease had reached Port-au-Prince, which had feared an outbreak since October.

About 170 people are now being treated in hospitals in the city, according to the Pan-American Health Organisation (Paho). One person has died.

Dan Epstein, a Paho spokesman, said the organisation expected 270,000 Haitians to be infected by the disease in "between six months and a year", according to modelling based on a past outbreak in Peru.

The disease broke out in the Artibonite River valley in central Haiti in mid-October and initially seemed to have been contained, but cases have since soared.

Officials are warning that a sizeable outbreak in Port-au-Prince, where 1.3 million earthquake survivors live in tents, is now likely.