A man suffering cholera symptoms holds his serum bag as he is treated in Robine, Haiti, on Saturday. A spreading cholera outbreak in rural Haiti threatened to outpace aid groups as they try to keep the disease from reaching the camps of earthquake survivors in Port-au-Prince. (Ramon Espinosa/Associated Press)An outbreak of cholera is worsening in Haiti, and moving closer to the country's earthquake-devastated capital, Port-au-Prince.

As of the most recent reports on Saturday evening, the disease has killed at least 208 people and sickened another 2,674.

There are concerns tens of thousands of people made homeless by January's earthquake could be at risk.

The outbreak began in the rural Artibonite region, which hosts more than one million quake refugees. Cases have now been confirmed outside of Artibonite, in Arcahaie, a town closer to the capital.

Health officials fear what could happen if the disease spreads to Port-au-Prince, where hundreds of thousands of quake survivors live in tarp camps.

"If the epidemic makes its way to Port-au-Prince, where children and families are living in unsanitary, overcrowded camps, the results could be disastrous," said Dr. Estrella Serrano, World Vision's emergency response health and nutrition manager.

Reuters reported that UN humanitarian spokeswoman Imogen Wall said five cases of cholera have been reported in Port-au-Prince, but she said those people contracted the disease in the Artibonite region before they returned to the capital and became sick.

"They were very quickly diagnosed and isolated," Wall told Reuters. "This is not a new location of infection."

A boy suffering from cholera sleeps while waiting for medical treatment at a hospital in the Marchand Dessaline zone, about 36 kilometres from the town of Saint Marc, on Friday. (St-Felix Evens/Reuters)Cholera is a waterborne bacterial infection spread through contaminated water. It causes severe diarrhea and vomiting that can lead to dehydration and death within hours. Treatment involves administering a salt-and-sugar-based rehydration serum.

Red Cross spokeswoman Julie Sell said that beginning Monday teams would begin teaching disease prevention to people living in the refugee camps.

"We are taking this very seriously, but we also want to make sure that every one of our people have the information they need," she said.

With files from The Associated Press