(CBS News) A natural disaster occurred in Haiti in 2010 when a devastating earthquake hit that nation. It was quickly followed by a devastating epidemic of cholera. Victims blamed United Nations peacekeepers for bringing the disease to the country. Now they're filing an unprecedented lawsuit seeking billions.
With 10 million people and little access to clean water, the country was hardly prepared for a cholera epidemic.
Lizette Paul's family has been torn apart. Her daughter, brother, and father all died.
"When I think about them," Paul told us, "I know the pain they had to go through before they passed away."
Paul is now one of those suing the United Nations for bringing cholera to the country -- an epidemic that began after U.N. peacekeepers arrived following the earthquake in 2010.
Nicole Phillips is the attorney handling the case from Port-au-Prince. Asked if outbreak would have happened had the United Nations weren't in Haiti after the quake, Phillips said no.
"The people thought that water was safe to drink, and they kept drinking it," she said. "And now that cholera has spread so far into the river systems that it would be impossible to eradicate."
Forensic studies have linked the spread of the disease to a flawed sewage system at the U.N.'s base for soldiers from Nepal. A United Nations test showed the culprit bacteria came from Southeast Asia.
Cholera, spread through human feces, induces severe vomiting and diarrhea, and can kill if not treated quickly.
A section of river in Mirebalais, about an hour drive northeast of Port-au-Prince, is believed to be the source of the outbreak. Haitians use the water to cook, clean and bathe with. Up until 2010, they said they never had a problem.
CBS News visited a clinic that is still full, run by Oliver Schultz, of Doctors Without Borders. "The problem in Haiti is bad," he said. "It is the worst cholera epidemic in modern times. There are more numbers here than probably even worldwide alone in this year."
The U.N. said it has legal immunity and will not accept claims for compensation.
What makes Lizette Paul think she can win this? "We're getting a lot of help," she told us, "and we hope to God we can win."
With her brother and father gone, the family has no breadwinner, and no money for the surviving children to attend school. Winning this case, Paul believes, could give them a future.
And while the lawsuit moves forward, the same strain of cholera also continues to spread. It's already been found in the Dominican Republic, Cuba and now Mexico.
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