NEW YORK // The United Nations is tightening its deployment rules in response to an internal report that says Nepalese peacekeepers may inadvertently have brought a killer strain of cholera to Haiti after last year's earthquake.
Under a directive first issued in late October, countries that contribute troops to UN peacekeeping missions around the world will now be required to vaccinate their personnel, Michel Bonnardeaux, a spokesman for the UN's department of peacekeeping operations, said.
A cholera outbreak that struck Haiti at the beginning of October last year killing more than 5,000 people and infecting 300,000 others was blamed by many Haitians on Nepalese peacekeepers who were posted to the town of Mirebalais, about 60km north of the capital, Port-au-Prince.
Angry protesters demanded the peacekeepers leave Haiti, pointing to cracked water pipes from latrines on their rural base that leaked waste into the Artibonite River, used by locals for washing, cooking and drinking.
Ban Ki-moon, the UN secretary-general, appointed experts to investigate the January outbreak of cholera, which causes severe diarrhoea and can kill children and adults in less than 12 hours. Their 32-page report released last week was inconclusive, but pointed to the Nepalese base as a possible source of the bacterial disease.
The four-member panel said there had been no cases of cholera in Haiti for almost a century. They concluded that the South Asian strain of the disease had been introduced from abroad and traced it to the area of the Nepalese outpost.
The report described "faecal waste" as a possible source of the epidemic and said the "sanitation conditions at the Mirebalais ... camp were not sufficient to prevent faecal contamination of the Meye tributary system of the Artibonite River".
But the panel did not directly accuse the Nepalese peacekeepers, saying the outbreak was "not the fault of, or deliberate action of, a group or individual". Instead it blamed a "confluence of circumstances" for spreading the disease.
The "explosive spread" of cholera was attributed to poor water and sanitary conditions in Haiti, widespread use of Artibonite waters, the migration of those infected and poorly serviced hospitals and clinics in the quake-struck country.
Mr Bonnardeaux said a UN task force would review the report and that peacekeeping chiefs would decide whether to insist on anti-cholera vaccinations and other measures to prevent similar epidemics elsewhere.
The outbreak raised concerns about UN deployments globally. The world body has more than 99,000 personnel deployed in 14 operations - mostly troops from developing countries sent to turbulent parts of Africa and Asia where diseases such as cholera are endemic.
It also poses problems for charities that assist in wars and natural disasters. "After an earthquake and with only 24 hours to deploy, you may not have time for a medical check," Cinta Pluma, a Haiti-based spokeswoman for Oxfam, said.
Les Roberts, an expert on population and health at New York City's Columbia University, said the cholera outbreak in Haiti arose from a rare set of conditions and there was no need for the UN to overhaul its peacekeeping policies.
"This was a fluke circumstance and it would be unfortunate for the UN to radically change its response capacity," he said.
The cholera outbreak was unlikely to be repeated elsewhere since UN deployments were typically in zones where the disease was already endemic, he said. Haitians were vulnerable because they had no immunity to the gut infection.
Cholera can be carried by people who show no symptoms, which meant it was probably brought to Haiti unwittingly, Mr Roberts said. This was not the case with infections such as dysentery and typhoid.
Dr Scott Dowell, who led the Haiti cholera response for the US-based Centres for Disease Control and Prevention, said the disease was ruled out of risk assessments after the earthquake and the epidemic last October caught aid workers off guard.
"We thought cholera was unlikely because it had not been in Haiti for a century or so. But there is no doubt in my mind that [view] will be revisited. People will think about this experience for future humanitarian operations," Dr Dowell said.
Haiti's president-elect, Michel Martelly, who will take office on Saturday, has put tackling the cholera epidemic high on the national agenda. It is feared the country's rainy season will bring a resurgence of the disease which spreads in contaminated water.
The earthquake last year claimed 316,000 lives and left more than a million people homeless. More than 600,000 Haitians still live in makeshift camps.