PORT-AU-PRINCE, Haiti (AP) — The death rate from the Haiti cholera epidemic that has killed more than 7,000 people over the past two years has finally ebbed, but the debate about the source of the disease has only grown more heated.
That renewed controversy came into sharp focus following the recent release of a study led by a University of Maryland cholera expert renowned in the scientific community.
Challenging prevailing wisdom, the study found that Haiti had not just one cholera strain but a second one that may have been lurking undetected prior to the arrival of a United Nations peacekeeping battalion from Nepal. Many finger the battalion as the chief culprit for a disease that has sickened more than half a million people. The study fell short of explicitly blaming the epidemic on the newly discovered strain but said it was a factor.
It was enough to reignite discussion about the disease and heighten political tensions between two camps who have argued over whether it was humans or the environment that could've introduced cholera to Haiti.
"Those are the two groups duking it out," said Judith Johnson, a professor of pathology and clinical microbiology at the University of Florida. Johnson described the episode as a "clash of the titans."
Report author Rita Colwell, a former director of the U.S. National Science Foundation, said she wasn't taking sides in the debate: "I'm not attacking anyone; I'm a scientist."
Regardless, her paper, published in the respected journal Proceedings of the National Academy of Sciences, challenged the view that the U.N. was responsible for the deadly disease. Instead, it argued, a "definitive statement of source attribution cannot yet be made" as it called for the creation of a public database to study cholera strains.
The report added that a "perfect storm" of environmental circumstances in 2010 enabled the bacteria to surface, as the impoverished country was hit by a massive earthquake, a hurricane and a "very hot summer season."
Only a few months after a massive earthquake hit the country, cholera had popped out of seemingly nowhere even though there had been no previously documented cases of cholera, according to researchers at Duke University.
Following the outbreak in Haiti's biggest river, the Artibonite, the disease raged through the country's waterways and appeared in all 10 administrative departments a month later.
It seemed inevitable that the disease would circulate so easily. Cholera, whose symptoms consist of rapid dehydration and vomiting, is spread through water or food contaminated by the bacterium, easily so in Haiti because the country lacks a proper sewage and sanitation system.
The scene turned ghastly. People fell dead in the streets. Government employees scooped up bodies and buried them. Aid workers stretched thin by the earthquake set up makeshift rehydration units, handed out soap and clean water and tried to save lives.
"If you have cholera, you and death are so close together," recalled 59-year-old Pierre Antoine, who was holed up at a treatment center with the illness for two weeks. "I don't wish this upon anyone."
The report's findings have met plenty of scientific pushback. Many scientists say the second cholera strain cited by the report was unlikely to have caused the outbreak because it's nontoxic, naturally inhabits bodies of water around the world and is unlikely to trigger epidemics. Unlike the strain that sickened so many Haitians, this one is believed to cause only mild diarrhea and isn't life-threatening.
French epidemiologist Renaud Piarroux pointed out how Hurricane Tomas came two weeks after the outbreak began and that a decade-long review of temperatures revealed no evidence of unusually high temperatures that summer.
"The perfect storm is a perfect lie," said Piarroux, who's writing a book on the source of cholera in Haiti. "This is not a scoop. It means nothing."
Drawing on 50 years of data pulled from the National Oceanic and Atmospheric Administration, Colwell maintains that 2010 was a warm year with "anomalously high air temperatures" in the months before the outbreak. This, in combination to the destruction of water and sanitation access, as well as widespread flooding caused by the hurricane, created conditions that would favor the outbreak.