Compelling new scientific evidence suggests United Nations peacekeepers have carried a virulent strain of cholera -- a super bug -- into the Western Hemisphere for the first time.
The vicious form of cholera has already killed 7,000 people in Haiti, where it surfaced in a remote village in October 2010. Leading researchers from Harvard Medical School and elsewhere told ABC News that, despite UN denials, there is now a mountain of evidence suggesting the strain originated in Nepal, and was carried to Haiti by Nepalese soldiers who came to Haiti to serve as UN peacekeepers after the earthquake that ravaged the country on Jan. 12, 2010 -- two years ago today. Haiti had never seen a case of cholera until the arrival of the peacekeepers, who allegedly failed to maintain sanitary conditions at their base.
"What scares me is that the strain from South Asia has been recognized as more virulent, more capable of causing severe disease, and more transmissible," said John Mekalanos, who chairs the Department of Microbiology and Immunobiology at Harvard Medical School. "These strains are nasty. So far there has been no secondary outbreak. But Haiti now represents a foothold for a particularly dangerous variety of this deadly disease."
More than 500,000 Haitians have been infected, and Mekalanos said a handful of victims who contracted cholera in Haiti have now turned up in Venezuela, the Dominican Republic, and in Boston, Miami and New York, but only in isolated cases.
How cholera landed in Haiti has been a politically charged topic for more than a year now, with the United Nations repeatedly refusing to acknowledge any role in the outbreak despite mounting evidence that international peacekeepers were the most likely culprits. The UN has already faced hostility from Haitians who believe peacekeeping troops have abused local residents without consequence. They now face legal action from relatives of victims who have petitioned the UN for restitution. And the cholera charge could further hamper the UN's ability to work effectively there, two years after the country was hobbled by the earthquake.
Over the summer, Assistant Secretary General Anthony Banbury told ABC News that the UN sincerely wanted to know if it played a part in the outbreak, but independent efforts to answer that question had not succeeded. He said the disease could have just as easily been carried by a backpacker or civilian aid worker.
Banbury said the UN, through both its peacekeeping mission and its civilian organizations "are working very hard ... to combat the spread of the disease and bring assistance to the people. And that's what's important now."
"The scientists say it can't be determined for certainty where it came from," Banbury said. "So we don't know if it was the U.N. troops or not. That's the bottom line."
A UN spokeswoman repeated the answer when asked again last week: "The [scientists] determined it was not possible to be conclusive about how cholera was introduced into Haiti," said the UN's Anayansi Lopez.