PEUREULAK, Indonesia, April 26, Reuter - A cholera epidemic sweeping the northern Sumatran province of Aceh has killed at least 55 people and put 6,000 in hospital, Indonesian health officials said on Friday.

The epidemic began in March at the start of Ramadan, the Moslem fasting month, and spread across the province as people flooded back to their villages for the Moslem holidays.

It reached a peak in the holiday week when people buy a traditional coconut ice drink from street vendors. Because of a drought in the area vendors used ice made from unboiled water intended for packing fish, according to a government official.

Doctors and health workers said the drought had caused people to relegate hygiene as a priority.

"When you walk two kilometres each way for your water you drink it, you don't wash your hands with it," said a doctor who has treated 117 cholera cases in Peureulak on Aceh's east coast.

In his hospital, children lie weak and wide-eyed as nurses insert rehydrating drips into their arms.

"We're the lucky ones. We have all the medicine we need," the doctor said. Only three of his patients have died.

In Pidie to the north, health workers said medicines were begining to arrive, but too late for many.

"It's sickening to sit there and watch people die just because you don't have the drips," said a health worker whose clinic was bursting at the seams with people needing treatment.

Cholera, spread through infected food and water, strikes quickly. Within hours of the first vomiting and diarrhoea, the body is so dried out that liquids have to be injected directly into the veins.

If caught right at the start, drinks of boiled water, sugar and salt can bring dehydration under control but if nothing is done cholera can kill in less than 24 hours.

During the fasting month, the strictly-Islamic Acehnese were reluctant to drink between dawn and dusk even to stem dehydration, doctors said.

And in Aceh, where troops are fighting separatist rebels, few people venture out after dark even in areas with no official curfew. Doctors said that keeps some cholera victims away from hospital until it is too late to save them.

In the Moluccan spice islands some 2,000 miles (3,000 km) to the east of Aceh "eltor" cholera killed nearly 100 people between December 1990 and February 1991.

The eltor strain of the disease is thought to be responsible for an epidemic that has felled 1,148 people in Peru and is threatening whole communities in the Amazonian jungles.

The World Health Organization announced on Thursday the formation of a global cholera task force to control the spread of the disease.