Zimbabwe's water, sanitation and health systems have collapsed
The death toll from the cholera outbreak in Zimbabwe has now passed the 3,000 mark, the UN's World Health Organization (WHO) has said.
The latest figures represent an increase of more than 1,000 deaths in just two weeks.
Meanwhile, the MDC's leader sounded more upbeat about power-sharing, a day after his party denied it had agreed to join a unity government next month.
He said it would go ahead if the rivals resolved their long-running disputes.
"Everyone agrees that, subject to the clearing of all the issues that are outstanding, a coalition government can be formed," Movement for Democratic Change leader Morgan Tsvangirai told South African newspaper The Star.
As the stalemate continues, Zimbabwe is lurching towards economic collapse.
The WHO said on Wednesday a total of 3,028 people have died from the cholera outbreak and 57,702 have been affected since August 2008.
The epidemic of the water-borne disease has been fuelled by the collapse of Zimbabwe's water, sanitation and health systems.
STATE OF ZIMBABWE
Five million people - almost half population - need food aid
Central bank introduced Z$100tr note, worth about US$30 (£20)
Unemployment more than 80%
Nearly 3,000 people dead in cholera outbreak
Many teachers, doctors and nurses not working
Aid workers say the focus of the cholera outbreak has now moved to rural parts of the country.
South Africa insisted the MDC had said it would join a unity government with President Robert Mugabe next month, despite the opposition's denial that it had agreed to do so at a regional summit this week.
Frank Chikane, director-general of South Africa's presidency, told reporters that observers should not "read too much" into the MDC's complaints.
Monday's 15-nation Southern African Development Community (SADC) meeting in Pretoria said the MDC was ready to form a unity government with Zanu-PF by mid-February.
SADC leaders also concluded that Zimbabwe's contentious home affairs ministry, which runs the police, should be controlled jointly and reviewed six months after the new government was inaugurated.
Home affairs has been a key sticking point, with the MDC insisting it should run the ministry if Zanu-PF is to administer the defence and national security departments.
The MDC also wants a share of regional governor and diplomatic posts.
President Mugabe and Mr Tsvangirai agreed to share power last September but the rivals have not been able to agree on how to allocate key government jobs.
The MDC, along with Western nations, accuses Mr Mugabe of not being sincere about power-sharing, pointing to a spate of abductions of opposition officials and human rights activists.