Port-au-Prince, Haiti ? A cholera outbreak that already has left 250 people dead and more than 3,000 sickened is at the doorstep of an enormous potential breeding ground: the squalid camps in Port-au-Prince where 1.3 million earthquake survivors live. Health authorities and aid workers are scrambling to keep the tragedies from merging and the deaths from multiplying.

Children suffering from cholera symptoms rest at the hospital in Grande-Saline, Haiti. A cholera outbreak in rural Haiti threatened to outpace aid groups as they stepped up efforts to keep the disease from reaching earthquake survivors.

Five cholera patients have been reported in Haiti’s capital, heightening worries that the disease could reach the sprawling tent slums where abysmal hygiene, poor sanitation, and widespread poverty could rapidly spread it. But government officials said Sunday that all five apparently got cholera outside Port-au-Prince, and they voiced hope that the deadly bacterial disease could be confined to the rural areas where the outbreak originated last week.

“It’s not difficult to prevent the spread to Port-au-Prince. We can prevent it,” said Health Ministry director Gabriel Timothee. He said tightly limiting movement of patients and careful disposal of bodies can stave off a major medical disaster.

If efforts to keep cholera out of the camps fail, “The worst case would be that we have hundreds of thousands of people getting sick at the same time,” said Claude Surena, president of the Haiti Medical Association. Cholera can cause vomiting and diarrhea so severe it can kill from dehydration in hours.

Robyn Fieser, a spokeswoman for Catholic Relief Services, said she was confident that aid groups and the Haitian government will be prepared to respond to an outbreak should it occur in the camps. But she stressed that the challenge of preventing its spread is “immense.”

“There are proven methods to contain and treat cholera, so we know what we’re dealing with. The biggest challenge is logistics, that is, moving massive amounts of medicine, supplies and people into place to treat them and prevent the disease from spreading,” Fieser said from the neighboring Dominican Republic.

Doctors Without Borders issued a statement saying that some Port-au-Prince residents were suffering from watery diarrhea and were being treated at facilities in the capital city. Cholera infection among the patients had not been confirmed, however, and aid workers stressed that diarrhea has not been uncommon in Port-au-Prince since the earthquake.

“Medical teams have treated many people with watery diarrhea over the last several months,” Doctors Without Borders said.

Aid workers in the impoverished nation say the risk is magnified by the extreme poverty faced by people displaced by the Jan. 12 earthquake, which killed as many as 300,000 people and destroyed much of the capital city. Haitians living in the camps risk disease by failing to wash their hands, or scooping up standing water and then proceeding to wash fruits and vegetables.

“There are limited ways you can wash your hands and keep your hands washed with water in slums like we have here,” said Michel Thieren, an official with the Pan-American Health Organization in Haiti. “The conditions for transmission are much higher.”

Aid workers are coaching thousands of impoverished families how best to avoid cholera. Various aid groups are providing soap and water purification tablets and educating people in Port-au-Prince’s camps about the importance of washing their hands.