Aid agencies and the United Nations need to do more to slow the spread of a cholera outbreak that has claimed at least 1,250 lives and made thousands in Haiti ill, an emergency medical organization says.

Ivan Gayton, an emergency co-ordinator for Doctors Without Borders (MSF) in Haiti, told CBC News on Monday that the UN and the international community "need to realize the urgency of this medical disaster."

Gayton said MSF has handled the majority of the cholera cases treated in Haiti to date, but more help is needed.

"We are not able to replace an entire Ministry of Health and UN apparatus, so we will need help and we will need other actors," he said. "It's absolutely necessary that others scale up and get rolling."

He said the Haitian government needs assistance because it has never dealt with a cholera outbreak and much of the country's health infrastructure was destroyed in the devastating Jan. 12 earthquake.

Gayton's comments come after MSF's statement Friday that the response to the outbreak of cholera — a disease of the small intestines characterized by diarrhea, vomiting and cramps — has been "inadequate in meeting the needs of the population."

The medical organization called on relief groups and agencies working in Haiti to "step up the size and speed" of their response efforts, saying more preventive actions and treatment sites are needed.

Nigel Fisher, the UN humanitarian chief in Haiti, said on the weekend that there has been a slow response to a UN appeal for roughly $164 million US to help slow the spread of the disease.

“While we are very grateful for the contributions received so far, both cash and in-kind, so far we only have received less than 10 per cent of what we need,” Fisher said.

Cases increase in capital

Gayton also said the number of cholera cases in the capital is "on the upswing."

"We're seeing 15 to 20 per cent more cases every day in parts of the capital."

A woman and child sit at the entrance to the intake tent at a cholera clinic set up by Doctors Without Borders in the Tabarre neighbourhood of Port-au-Prince on Friday. (Allison Shelley/Reuters)

CBC producer Sylvia Thomson said in a report from Haiti that 80 people were being treated for cholera at a single clinic in Port-au-Prince.

Aid efforts faced a major setback last week after the UN temporarily halted aid distribution in the north following a string of violent protests in Cap Haitien and several other communities.

The UN resumed aid distribution in northern Haiti on the weekend as protests waned.

From an ad hoc hospital in Arcahaie, about an hour's drive north of Port-au-Prince, CBC's Paul Hunter reported that aid workers there are struggling with the continuous inflow of patients from the hills around the town.

"They can barely keep up with the numbers, and I asked one of the aid workers here if they have the resources to deal with the tremendous number of patients that are coming in here daily — and in a word, his answer was 'no.' "

Hunter said the clinic, which was established by German Red Cross workers on Oct. 29, has treated 650 people and had about 68 die.

On Monday, another dozen people were lined up to get treatment, he said.

Four of the 19 candidates vying to replace President René Préval said Friday the election should be postponed to allow authorities to focus on the cholera outbreak, but the majority of the candidates have said the election should move forward.