Geneva - Zimbabwe faces potential "catastrophic" results if humanitarian efforts against cholera are not provided soon, an official with the Red Cross said Tuesday, as the UN confirmed that at least 978 people have died of the disease since August.

The UN statistics are generally seen as the minimum number of deaths and it is assumed the actual toll is higher. Some 18,413 suspected cases of the disease have been reported.

The rainy season about to hit Zimbabwe will likely exacerbate the spreading of the disease, triggered in part by the deteriorated state of the country's sewage system, aid workers said.

"The rain will only make it much, much worse," said John Roche with the International Federation of the Red Cross.

"If we don't do now what we need to do as a humanitarian community, it could be catastrophic," he added.

There was also mounting concern that the Christmas season, when migrant workers return home and then head back out again to neighboring countries for their jobs, could help spread the cholera.

UN agencies, charities and the Red Cross were working with the Ministry of Health in Harare to assess and combat the disease, but shortages of basic supplies, including medical equipment, food and fuel were complicating relief efforts.

"The underpinning humanitarian issue is the food," said Roche.

The World Food Programme estimates that by January about 5.1 million people, or 45 per cent of Zimbabwe's population, will require food aid, though funding has been limited, forcing the agency to scale down its rations.

Local medical staff also continue to face problems, including a lack of funds to travel to work. Medical centres were running on skeleton staffs, and in turn less people were showing up for treatment, the World Health Organization said.

In neighboring Angola, were there were about 10,000 suspected cases of cholera, aid workers said they will likely have to draw up response plans as well, while Mozambique teeters between a controllable outbreak and one requiring international assistance.

South Africa has already declared a disaster along its border with Zimbabwe. (dpa)