PORT-AU-PRINCE (Reuters) - The death toll in Haiti's cholera epidemic climbed on Thursday, reaching 800, according to a U.S. medical expert who expressed concern about risk of transmission to the United States and other countries.

Patients suffering are sprayed Patients suffering from cholera symptoms are sprayed with disinfectant at the Doctors Without Borders temporary hospital in Port-au-Prince, Haiti, Thursday, Nov. 11, 2010. (AP Photo/Ramon Espinosa)

 Fatalities from the diarrheal disease have risen steadily since the start of the outbreak more than three weeks ago in the poor Caribbean nation, which is struggling to recover from the effects of a devastating January 12 earthquake.

 Ezra Barzilay, an epidemiologist at the U.S. Centers for Disease Control and Prevention (CDC), said the health emergency created by the epidemic was worsening. "As of November 8, we had about 640 deaths. Today we are at 800," he said in a call from Haiti to participants at a medical conference in Biloxi, Mississippi.

 "The situation here is more dire every day. Haitians are in line (for treatment). Hospital beds are gone. Hospitals are completely overrun," he said, adding local medical staff were being forced into choices over which patients they treated.

 Haiti's health ministry said on Thursday that up to Tuesday, November 9, confirmed deaths from cholera totaled 724, with 11,125 hospitalized cases registered. Ten deaths had been recorded in the capital Port-au-Prince, where authorities fear contagion in crowded camps housing earthquake survivors.

Some residents of Gonaives are transporting a cholera victim to the hospital. (Photo may be copyrighted)

In his call to the Biloxi conference, CDC's Barzilay said U.S. health authorities were worried about the possibility of cholera spreading to Haiti's neighbors, including the United States, just two hours flying time away.

On its website, the Florida Department of Health said travel to and from Haiti had increased since the Haitian earthquake with travelers including relief workers and local Haitian residents visiting family in Haiti.

"Cholera does not spread easily in developed countries such as the U.S., but we want to be sure we do not miss any high-risk situations, like cholera in a food-handler, or clusters or outbreaks," the department said.

So afraid are citizens of cholera they don't even attempt to properly bury their dead. (Photo may be copyrighted)

Florida has some 241,000 Haitian-born residents, 46 percent of the Haitian-born population in the United States.

Haiti's epidemic, which experts believe was worsened by flooding caused by Hurricane Tomas earlier this month, has piled another humanitarian emergency on the Western Hemisphere's poorest state, whose capital was wrecked by the January 12 earthquake that killed more than 250,000 people.

Presidential and legislative elections scheduled for November 28 in the Caribbean nation are set to go ahead.

(Reporting by Joseph Guyler Delva in Port-au-Prince and Leigh Coleman in Biloxi; Editing by Pascal Fletcher and Vicki Allen)

Copyright © 2010 Reuters Limited.

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