HAVANA -- Cuba's Health Ministry on Saturday reported 158 cases of cholera, nearly three times as many as previously disclosed, but said there were no new deaths and the outbreak appears to have been contained and on the wane.

The ministry said Intensive efforts to quarantine those infected, hand out chlorine tablets and educate the population has meant a drop in cases transmitted by water, and there is no evidence of the disease spreading through the food supply.

Virtually all of the cases have come from the city of Manzanillo or from people who recently traveled from the area.

"We have diagnosed isolated cases in other regions of people that were infected in Manzanillo, all of whom were treated and studied quickly," the ministry said. "There has been no spread of the outbreak."

Cuba announced July 3 that three elderly people had died from the tropical disease and 53 people sickened in the first incidence of cholera on the island in decades. Until Saturday's report, authorities had said little more, prompting rumors of more deaths and a wider problem. Still, even in the infected area, hotel workers and residents said there was no panic.

Cuba has a well-organized civil defense system capable of rapidly mobilizing government agencies and citizens groups, as it does for tropical storms and hurricanes. Brigades of workers go door to door, eliminating standing water where mosquitos bearing another tropical disease, dengue, could breed.

The country also has thousands of well-trained doctors and nurses, many of whom played a key role in fighting a much deadlier cholera outbreak in nearby Haiti after that country's devastating earthquake.

A rise in cases of diarrhea and tropical diseases are normal in Cuba in the summer, due to the intense heat and heavy rains. In its communique on Saturday, the Health Ministry urged people to wash their hands, boil water and pay better attention to their personal hygiene.