WASHINGTON (Reuters) - The cholera epidemic that has killed 1,110 people and sickened thousands in Haiti is part of a 49-year-old global pandemic and likely was brought to the Caribbean country in a single instance, scientists said on Thursday.
But that was all it took to set off the epidemic, with an already weak sanitation system thrown into chaos by a devastating earthquake in January, the U.S. Centers for Disease Control and Prevention and the Pan American Health Organization said.
The epidemic in the poorest country in the Western Hemisphere could easily worsen and cholera could linger there for years, they said.
Many Haitians blame U.N. troops for bringing the sometimes deadly bacterial disease to the island nation, where 1.5 million people are still displaced after the earthquake. Anti-U.N. riots have disrupted efforts to fight the raging outbreak.
CDC infectious disease specialist Dr. Scott Dowell said it may be impossible to trace how the cholera came to Haiti. An infected person, contaminated food or even a ship's bilge water could all carry the bacteria, Dowell said.
Genetic fingerprints show the outbreak can be traced to a pandemic that started in Indonesia 49 years ago and has spread around the world, the CDC and PAHO said.
"Surprisingly, it has spared the Caribbean so far," Dowell said in a telephone interview. "Cholera has moved quite efficiently around Haiti and also moved efficiently around the world. It's hard to figure out where it came from."
Dowell said lives can be saved with quick and simple treatment and that is what health officials are focusing on.
Cholera can be treated with antibiotics but the usual best course is giving intravenous fluids, salts and sugars to restore what is lost through diarrhea and vomiting.
"As far as stamping it out or eliminating it from Haiti, we are not hopeful about that," Dowell said. "We feel that Haiti is going to be dealing with cholera for several years or several months at least."
Cholera is spread when the bacteria get into water, almost always via human waste.
Haiti had not seen cholera for 100 years but experts say conditions are ideal for its spread -- lack of proper sewerage, people forced to defecate in the open, a tightly packed population, torrential rains and a lack of clean water.
Genetic tests show the Vibrio cholerae bacteria from many samples are almost identical to one another, which supports the theory of a single source, the CDC and PAHO said.
"If these isolates are representative of those currently circulating in Haiti, the findings suggest that V. cholerae was likely introduced into Haiti in one event," the researchers wrote in the CDC's weekly report on death and disease.
HALF A CENTURY OF DISEASE
"V. cholerae strains that are indistinguishable from the outbreak strain by all methods used have previously been found in countries in South Asia and elsewhere," they said.
"Haiti is the latest country to be affected by the ongoing cholera pandemic, which began 49 years ago in Sulawesi, Indonesia, and has lasted longer and spread farther than any previously known cholera pandemic."
Most of the first cholera patients in Haiti worked in rice paddies in the Artibonite Department.
Health investigators interviewed 27 patients. The CDC and PAHO report said most drank untreated water from the Artibonite River or canals and 78 percent practiced open defecation.
"This is the breadbasket of Haiti," Dowell said. "If cholera gets into the Artibonite River, it gets distributed across Artibonite pretty efficiently. People have a lot of contact with river water."
Before the earthquake hit, only 12 percent of Haiti's population had piped, treated water and only 17 percent had access to adequate sanitation, the CDC and PAHO said. Now the situation is worse.
"The course of the cholera outbreak in Haiti is difficult to predict," the researchers concluded. "The Haitian population has no pre-existing immunity to cholera, and environmental conditions in Haiti are favorable for its continued spread."
Camps for Haitians displaced by the earthquake lack handwashing facilities and many do not have clean water.
"The number of cases might be lowered substantially if efforts to reduce transmission are implemented fully, but they also might be increased substantially by delays in implementation, flooding or other disruptions," the report said.
The World Health Organization reports that 221,226 cases of cholera and 4,946 deaths from the infection were reported from 45 countries in 2009 but the true toll was likely much higher.