Zimbabwe's sanitation and health infrastructure is dilapidated
The number of cholera cases in Zimbabwe is expected to reach 100,000 this week, according to the Red Cross.
While the infection rate has slowed, the underlying causes of Africa's worst cholera epidemic in 15 years have not been fixed, warned the aid group.
So far, 98,309 cases have been reported, with some 4,283 deaths, said the Red Cross in a report.
The outbreak, which began last August, has been fuelled by Zimbabwe's poor water, sanitation and health systems.
The International Federation of Red Cross and Red Crescent Societies (IFRCS) said infection rates of the easily-treatable water-borne disease had fallen by a quarter from a peak in February of 6% of the population to 4.5%.
But the report warned that unless factors such as food insecurity, and the dilapidated sanitation and health infrastructure were addressed, further cholera outbreaks were inevitable.
Zimbabwe's coalition government, formed in February between President Robert Mugabe and Prime Minister Morgan Tsvangirai, has pledged to make a priority of restoring eviscerated public services across the spectrum.
The IFRCS said it had been forced to scale back emergency aid measures after receiving only a small part of the donations it required.
Some $3.4m (£2.15m) was needed to rehabilitate Zimbabwe's water systems, dig wells and construct latrines, the aid group said.
"The government estimates the necessary rehabilitation of water and sanitation infrastructure will take years," said Stephen Omollo, the IFRC's representative in Zimbabwe.
The Red Cross said it had already provided nearly half a million people with access to clean water since its cholera relief mission to Zimbabwe was launched in December 2008.