The outbreak has heightened the humanitarian crisis in Zimbabwe, where President Robert Mugabe and the opposition are deadlocked over a power-sharing deal and the veteran leader is resisting Western calls to step down.
The World Health Organisation said this week that cholera had killed 1,608 people of 30,365 reported cases and the infection rate showed no signs of slowing. The disease has spread because of the collapse of health and sanitation systems.
Francoise Le Goff, head of southern African operations of the International Federation of Red Cross and Red Crescent Societies (ICRC), said the cholera risk was growing now Zimbabwe was entering the rainy season.
"We are just preparing for the worst," said Le Goff, who had just returned from a trip to Zimbabwe, adding that if the rains continue, the epidemic could last until March or April.
"The worst could be heavy rains causing not only this cholera to spread, but floods," said Le Goff.
"It means that the water level will cover the fields, that the crops are destroyed, that people cannot travel or we cannot have access to the area."
The cholera crisis could multiply to 60,000 cases and over 3,000 dead in the next three months, said Le Goff, citing WHO estimates.
The ICRC is the world’s largest disaster relief network.
Zimbabweans are already suffering from hyper-inflation and severe food, fuel and foreign currency shortages. There is not enough money to pay doctors and nurses or buy medicine in a country once seen as among Africa’s most promising.
Cholera, which causes severe diarrhoea and dehydration, has spread to all of Zimbabwe’s 10 provinces.
Le Goff said the Red Cross was concentrating on moving treatment centres closer to areas hit by cholera, educating people on the disease and providing clean water and sanitation.
The economic crisis has deprived local authorities of badly needed resources needed to fight the disease. Chronic fuel shortages have left Zimbabweans without transport.
Many have to travel long distances for treatment. Some never make it in time.
"If you need to walk 50 km (30 miles) to access a centre you will definitely have time to lose your fluids before you arrive," said Le Goff.
"What we have to make sure of is they have time to arrive and get the proper treatment."