"A decision has been taken to declare cholera as a national emergency," a source at the health ministry told AFP on condition of anonymity.

"The decision followed a cholera situation report which revealed that a total of 176 people have so far died out of 10 800 reported cases recorded between January 1 to August 14 and signs of the disease spreading to various parts of the country."

The decision was announced after a meeting between government and officials from the World Health Organisation and UN children agency UNICEF. Government has also set up a special task force to deal with the epidemic.

According to the health ministry, out of eight of the country's 12 districts which are affected by the outbreak, the western area which includes the capital Freetown has been worst hit with 63 deaths.

Other badly affected districts are Port Loko in the north of the country, where 43 people have died and Moyama in the south where 35 people have died.

Health ministry spokesman Abass Kamara rejected criticism from the public that government was doing little to stem the tide of the outbreak.

"A series of robust resource mobilisation including the setting up of dozens of cholera treatment units in affected areas have been undertaken."

State doctor Harrison Williams said patients came from areas with limited access to proper water drainage and sanitation as the country is at the height of its rainy season.

"We are many times overstretched working from mornings to late evenings. The unprecedented rainfall which is dislodging clogged-up gutters and bringing garbage into the streets has added to the filth."

The small west African nation of six million people has one of the worlds worst health systems with only one doctor per 34 744 people, according to UN figures.

The water-borne disease has also hit Guinea, neighbouring Sierra Leone to the north, leaving 60 people dead in that country since February, and Mali and Niger have also been hit by the outbreak.

Poor water and sanitation systems give rise to the disease, an acute intestinal infection caused by ingesting contaminated food and water which causes acute diarrhoea and vomiting and can kill in hours, according to the World Health Organisation.