Haiti cholera cases detected in Port-au-Prince
Five cases of cholera have been detected in Haiti's capital, Port-au-Prince, the UN says, amid an outbreak that has killed more than 200 people.
UN officials said the patients had been quickly diagnosed and isolated.
They became infected in the main outbreak zone - the Artibonite region - and then travelled to the capital where they developed symptoms, the UN said.
This meant Port-au-Prince was "not a new location of infection", the UN's humanitarian affairs agency said.
"The identification of the five cases in the capital, while worrying, also demonstrates that the reporting systems for epidemic management are functioning," said the UN Office for the Coordination of Humanitarian Affairs, or Ocha.
More than a million survivors of Haiti's devastating January earthquake are crowded into tent cities around Port-au-Prince with poor sanitary conditions and little access to clean drinking water.
Aid officials have described the prospect of cholera in the city as "awful".
Those in the camps are highly vulnerable to the intestinal infection, which is caused by bacteria transmitted through contaminated water or food.
Cholera causes diarrhoea and vomiting leading to severe dehydration, and can kill quickly if left untreated through rehydration and antibiotics.
'Slower pace of increase'
With 2,674 cases of the disease reported, health officials have been trying to contain the outbreak in Artibonite and Central Plateau.
They said they had stepped up disease prevention measures and surveillance at the tent camps, and sent medical teams north to treat those infected so they did not travel to the capital to seek help.
Ocha also said five cholera treatment centres were being built in the Port-au-Prince, most attached to hospitals or clinics.
"The hospitals in Port-au-Prince seem more prepared now for cholera to hit the area but the situation is far from under control," said Carel Padre.
"Everybody is worried about the disease reaching this dense city where there is a lack of sanitation and nowhere clean to cook or sleep," he told the BBC.
On Saturday, Ocha reported that the severity of the outbreak seems to be lessening in the southern Artibonite but its continued spread in the north of the region remained a concern.
"Although there is an increase in the number of confirmed cases, it is increasing at a slower pace than in previous days, which is a possible indication that some of the prevention and treatment measures are taking effect," Ocha said.
Meanwhile, officials confirmed that 194 people had died of cholera in Artibonite, and another 14 in Central Plateau.
The worst-hit areas were Saint-Marc, Grande Saline, L'Estere, Marchand Dessalines, Desdunes, Petite Riviere, Lachapelle, and St Michel de l'Attalaye, said the UN.
A number of cases have also been reported in the city of Gonaives, and towns closer to the capital, including Archaei, Limbe and Mirebalais.
Local hospitals have been overwhelmed. Aid workers said many patients at the St Nicholas hospital in Saint-Marc were being forced to lie outside in the car park in unhygienic conditions, hooked up to intravenous drips.
The aid agency Medicins Sans Frontieres has set up a cordon around the hospital to control exit and entry to try to contain the spread of the outbreak.
Dr Jhonny Fequiere told the BBC that his hospital in Marchand Dessalines was also struggling to cope, and that he had seen dozens die.
"We are trying to take care of people, but we are running out of medicine and need additional medical care. We are giving everything we have but we need more to keep taking care of people," he said.
Some patients said they became ill after drinking water from a canal, but others said they were drinking only purified water. The Artibonite river, which irrigates central Haiti, is thought to be contaminated.
Haitian Health Minister Alex Larsen has urged people to wash their hands with soap, not eat raw vegetables, boil all food and drinking water, and avoid bathing in and drinking from rivers.
There are enough antibiotics in Haiti to treat 100,000 cases of cholera and intravenous fluids to treat 30,000, according to the UN.
This is the first time in a century that cholera has struck Haiti.