A cholera outbreak in the southern Democratic Republic of Congo (DRC) province of Katanga has spread, despite efforts to bring the epidemic under control.

The disease has claimed the lives of 97 people and 4,029 have been infected since the first cases of the gastro-intestinal illness were reported in Katanga in September 2007, according to François Dumont, spokesman for Médecins Sans Frontières (MSF-Belgium). The disease has spread quickly since the end of December.

"What is remarkable is that the peak of the epidemic has not yet been reached because the number of patients continues to grow," Dumont said.

Most of the cases have been reported in Lubumbashi, the provincial capital, where the death toll stands at 49 and the number of infections at 2,543, and Likasi, nearly 100km north of Lubumbashi, where 48 people have died and 1,486 cholera patients have sought treatment.

The government and MSF-Belgium have set up two centres in Lubumbashi where patients can seek treatment free of charge.

"Epidemiological data from the first week of February confirms an upward trend [of the epidemic] in Likasi," said Dumont.

He said 404 patients were registered in Likasi, with a population of about 350,000, at the beginning of February, compared with 381 during the last week of January.

"The rate of admissions remains very high - almost 60 new patients a day," said Dumont.

The epidemic has been blamed on the consumption of contaminated water and poor sanitation in the affected areas.

"We are very concerned, primarily over the lack of access to clean water in residential areas of Lubumbashi and Likasi. If we want to contain the cholera epidemic much more must be done on the water sector," said Dumont.

Cholera is a gastro-intestinal disease typically spread by drinking contaminated water and can cause severe diarrhoea which, in extreme cases, can lead to fatal dehydration. It can be prevented by treating drinking water with chlorine and by improving hygiene conditions.