The United Nations says at least 294 people have died while more than 6,000 cases of the deadly water-borne disease have been detected.
Zimbabwe's hospitals and clinics struggle to provide patients with even basic drugs and equipment, prompting scores of people to seek help in neighbouring South Africa.
Health officials in the South African border town of Musina say their local hospital has treated 168 cholera patients so far, with 27 still in hospital.
Three people have died in Musina, said Phuti Seloba, spokesman for the city's health department, while a fourth died last weekend in the southeastern coastal city of Durban.
The death in Durban, of a truck driver who had just returned from Zimbabwe, has raised alarms across South Africa that the nation could be at risk.
Health experts from the two countries met at the weekend to lay out a plan for tackling the outbreak, Seloba said.
"During the meeting, held in the Zimbabwean border town of Beitbridge, we all realised that the problem is neither Zimbabwean nor South African," he said.
"We realise that Zimbabwe lacks health equipments and drugs," he said.
"This is our common problem and we need to solve it jointly. We need to look at the health gaps and find a way to fill them by tackling the source of the problem," he added.
But health experts say the source of the problem is Zimbabwe's decade-long descent into economic chaos, crushing the nation's infrastructure under the weight of the world's highest inflation rate, last estimated at 231 million percent in July.
Basic water and sanitation services have broken down across the country, and with the start of the rainy season, raw sewage and drinking water are flowing into each other in towns around the country.
Zimbabwe's official death toll stands at 281, but even the government acknowledges that cholera is appearing in new towns almost every day.
"We have put maximum efforts to control the spread of the disease to different places throughout the country," said Madzudzo Pawadyira, head of the Civil Protection Unit.
The charity Doctors Without Borders estimated last week that 1.4 million people, just in and around the capital Harare, are at risk of the disease.
Zimbabwe's health system was once the envy of Africa, but now doctors and nurses say they struggle to treat even simple ailments in a country with one of the world's worst AIDS epidemics and chronic food shortages.
The United Nations estimates that five million people, nearly half the population, will need food aid in January.
The response to the cholera crisis has been hampered by Zimbabwe's political turmoil following disputed elections earlier this year.
President Robert Mugabe, the country's only ruler since independence in 1980, and opposition leader Morgan Tsvangirai signed a power-sharing deal two months ago but have yet to agree on the composition of a unity government.
South Africa will host new talks Tuesday to salvage the deal, with the ruling party leader Jacob Zuma warning that repeated delays were claiming people's lives.
"Let us find a way to implement the agreement for the sake of Zimbabweans," he told reporters. "It is now an urgent matter, because people are dying."