This is how the epidemic has played itself out to date:

• September 2008
• November 2008
• December 2008
• January 2009
• February 2009
• March 2009
• April 2009

• 11
• 19

11 people die in a Harare suburb. Authorities are blamed for failing to upgrade the sewer system to match the growing population of the suburb (originally built for 30 000 people, now houses nearly 1 million).
Zimbabwean water authority announces it cannot import enough water treatment chemicals because of the economic crisis in the country.

Norway gives Zimbabwe $7 million to cope with outbreak, and pay for food and clean drinking water.

• 19

Rehydration centre set up in South Africa near the Zimbabwean border to treat cholera patients, in order to relieve pressure at hospitals.
Musina Health Department spokesperson, Phuti Selobi, says South Africa is not facing a cholera threat because it does not share a common water source with Zimbabwe.

• 1
• 4
• 5
• 11
• 15
• 23
• 29

The Zimbabwean capital of Harare – in a gesture that could be seen either as magnanimous, or as a tacit admission of fault – announces it will give free graves and coffins to citizens who succumb to cholera.

Riot police charge into a group of doctors and nurses protesting Zimbabwe's deepening economic and health crisis.

Zimbabwe declare a national emergency, and state media report the government is seeking more international help to pay for food and drugs to combat the crisis. Britain offers 3 million pounds and sets aside a further 7 million in relief aid for Zimbabwe to provide medicine, fund basic health services and help prevent more cholera outbreaks. The US Agency for International Development says it will provide an additional $600 000 to help combat the outbreak. The European Commission provides more than $12 million for drugs and clean water and the International Red Cross ships in more supplies.

The Limpopo provincial government declares the Vhembe area a disaster area following a visit by South Africa's Health Minister Barbara Hogan.

Water resources in Musina and surrounding areas test negative for cholera, but suspected cases still increasing. Gauteng confirms cholera in 16 of the 46 people who present with symptoms.

The UN warns that 5.5 million people in Zimbabwe, about half the population, urgently need food aid.
Death toll in Zimbabwe now 1 123 out of about 21 000 reported cases (UN figures).

Death toll in Zimbabwe stands at 1 500 (UN figures), with fatality rates increasing. Total reported cholera cases in Zimbabwe: 26 497 since August. The UN says the outbreak is still out of control.

• 2
• 5
• 6
• 8
• 12
• 13
• 26
• 30

Red Cross announces it will send 7 international emergency response teams to Zimbabwe to help fight the spread of the disease.

The World Health Organisation announces that the total number of cholera deaths in Zimbabwe stands at 1 732, out of the 34 306 infected. The disease has spread to all Zimbabwe’s 10 provinces due to collapse of health and sanitation systems. The rainy season (January to March) is expected to exacerbate that problem.

21 reported cases in Gauteng, and 3 deaths.

First case in KwaZulu Natal confirmed.

Parts of the Tubatse River in Limpopo test positive for cholera in areas where people collect water for domestic use. Limpopo Water Affairs investigate whether water was contaminated by humans or the environment.
7 cases confirmed in the Western Cape.
2 new cases reported in the North West, bringing total to 4.
Zimbabwe's striking doctors and nurses turn down a new pay increase offer of US$50 to US$850, insisting on their original demands that their salaries be raised to at least US$2 000.

52 new cases reported in Limpopo, pushing the total to 1 854.
The total number of cases in South Africa since August 2008 stands at more than 38 000.
Death toll in Limpopo stands at 9, while the total number of cholera deaths in Zimbabwe stands at 2 024.
The World Health Organisation calls it “the largest ever recorded outbreak of cholera in Zimbabwe”.

The Red Cross warns that Zimbabwe's cholera epidemic is "far from under control". The outbreak has claimed the lives of 2 773 people so far, and more than 50 000 people have been infected since August. The WHO expect the caseload to exceed 60 000 by the end of the week. In South Africa, 5 696 people have been diagnosed with cholera. Thirty-six of them have died. – (Reuters Health/Sapa/Wilma Stassen)

The World Health Organisation says that Zimbabwe's cholera outbreak, one of the world's largest ever recorded, is far from being brought under control and an urgent response is needed to reverse the epidemic. Up to date, more than 60 000 people have been infected and over 3 100 have died due to cholera since August 2008.

The Mail and Guardian today reported that the cholera outbreak in southern Limpopo and central Mpumalanga is the result of poor service delivery and has nothing to do with the cholera crisis in neighbouring Zimbabwe. No new cholera cases were diagnosed in South Africa this week.

• 20

The World Health Organisation says the number of cholera cases in Zimbabwe has increased to over 80 000. According to the latest WHO figures, 3 759 have died of cholera while 80 250 people have been infected.

About half of the patients who died from the water-borne diarrhoeal disease failed to reach any of the country's 365 cholera treatment centres, the United Nations agency said.

• 9
• 16

The death toll from Zimbabwe's cholera epidemic has topped 4 000, and more than 89 000 have fallen sick, the United Nations said. The UN in Geneva said the death toll in Zimbabwe was now 4 011.

In South Africa the disease has killed 59 people and infected 12 324 since it spread from Zimbabwe in November. Health minister Barbara Hogan says it is now under control.

More than 91 000 cases of cholera have been reported in Zimbabwe, killing 4 035, according to the latest World Health Organisation data.

The WHO said earlier this month that the outbreak was showing signs of slowing, with the number of cases averaging 4 000 to 4 500 a week compared to peaks of nearly 8 000 earlier in the outbreak.

• 24

APRIL 2009

Cholera epidemic in southern Africa continues to abate; authorities stress the need to remain vigilant. 3-17 April: 4579 new cases in Angola, Botswana, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe. Cholera could re-appear in next 1-3 weeks, when floodwaters in region become stagnant. Cumulative total of cholera cases reported in southern Africa since August 2008: 155 692; 96 718 of those in Zimbabwe. Total reported deaths: 4686; 4218 of those in Zimbabwe.

Cholera is not unique to the situation in Zimbabwe, and is a regular occurrence in the developing world.

In fact, between 2000 and 2003 South Africa suffered an outbreak of the disease focused on KwaZulu-Natal, though people from Gauteng, Mpumalanga and the Northern Province were also affected. From August 2000 to July 2001, 106 389 people had been infected and 232 had died.

In 2003, when the epidemic was dying out, 3 901 cases were reported in Mpumalanga, the Eastern Cape and Kwazulu-Natal, and 45 deaths occurred. From 2003 to 2005 (which are the latest World Health Organisation statistics available) 3 000+ cases of cholera continued to occur in South Africa each year.

A curable disease
Cholera is a bacterial infection causing profuse watery diarrhoea which can lead to death by dehydration or shock. In a common scenario, the disease progresses from the first liquid stool to shock in 4 to 12 hours, with death following in 18 hours to several days, unless oral rehydration therapy is provided.

Transmission to humans occurs through eating food or drinking water contaminated with cholera vibrios.

Cholera epidemics usually occur in areas where there's poor sanitation, overcrowding, war or famine. But cholera can also spread after a natural disaster such as a flood or earthquake when fresh water supplies are disrupted.