The cholera outbreak in Haiti is "one of the largest epidemics of the disease in modern history to affect a single country," the U.N. World Health Organization's Pan-American Health Organization said in a news release.
Jon Andrus, the PAHO deputy director, said about 200 new cholera cases a day are reported in Haiti and the number will increase during the coming rainy season, which begins in April.
Andrus said in the U.N. release eliminating cholera will require "major investment" for decades to ensure safe water and sanitation for all residents.
The disease has spread from Haiti to the neighboring Dominican Republic, where 21,000 cases and 363 deaths from cholera have been reported, Andrus said.
The magnitude-7 Haiti earthquake, which struck 16 miles west of Port-au-Prince, and aftershocks killed an estimated 316,000 people and left 1.5 million people homeless, the Haitian government says. Many still live in tents and unsanitary conditions.
Most people in Haiti lack public sewage systems or sanitary latrines, and Haitians often drink from the same water they use to bathe and defecate.
Louise Ivers, senior health and policy adviser for U.S.-based aid organization Partners in Health and a Haiti resident, told USA Today people in rural areas often live hours from a water pump with clean water, and many cannot afford soap to wash their hands or fuel to boil water and kill the cholera organism.
"We have the luxury in the United States of potable water at our fingertips," Ivers said. "It's not a question in Haiti of ignorance. It's access."
Haiti's Health Ministry is to work with Partners in Help to begin giving 100,000 people in a Port-au-Prince slum and a rural community an oral cholera vaccine, Ivers said.
Cholera causes severe diarrhea and, without immediate treatment, can lead to dehydration. That, in turn, can lead to shock, which can cause death.
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