An outbreak of cholera in Zimbabwe is a sign that the nation's water and sanitation systems have failed, public health officials say.
The World Health Organization estimates that nearly 1,000 people in Zimbabwe have died of cholera since August, and more than 16,000 have been sickened. WHO officials predict the outbreak could spread to more than 60,000 people in the coming months.
Cholera is caused by bacteria that multiply in the intestine and cause severe diarrhea. Infected people can die from dehydration in less than a day. The disease spreads when bacteria from infected people gets into drinking water supplies.
In the past, that rarely happened in Zimbabwe, which had one of the best water and sewer systems in Africa. But in recent years, under President Robert Mugabe, the nation's infrastructure has crumbled.
This year, sewers have become broken or blocked, and officials have run out of money to buy chemicals that kill bacteria in drinking water.
"They used to have a very safe, modern system, and now that system is no longer being maintained," says Andra Tamburro of Water Advocates in Washington, D.C. "So people are going now back to their traditional sources, whether it be rivers or wells, and they have been contaminated with the cholera bacteria."
The situation is likely to get worse now that Zimbabwe's rainy season has begun, Tamburro says, because rain tends to carry untreated sewage into water supplies.
The lack of clean water is a new problem for people in Zimbabwe, says Duncan Steele, who grew up there and now works for the international health organization PATH.
Steele says that as recently as last year, he didn't hesitate to drink the tap water in hotels in Zimbabwe's capital, Harare.
But now that cholera has become established in the city's water supply, he says, "it's going to take considerable effort to get rid of it and get back to a situation where people can feel safe with the water they're drinking. It is a very negative development."
Steele says there are vaccines that can help prevent cholera, but they are not useful for stopping outbreaks because it takes several weeks before they offer any protection against sickness.