HAVANA (AP) -- Authorities in eastern Cuba are in full prevention mode to contain a rare cholera outbreak amid fears that it may have spread to the capital, distributing chlorine and water purification drops and quarantining hospital patients with diarrhea until they are checked for the disease.

In the eastern city of Manzanillo, in Granma province, cars crawl through the streets with loudspeakers reminding people of the importance of good hygiene, and the sale of oysters at private kiosks has been suspended, according to several residents interviewed by The Associated Press. But there has been no travel quarantine on the city, and the streets are calm even if some people are jittery.

"I haven't seen any panic or anything like that," David Chavez, a 40-year-old computer worker, said by phone from Manzanillo, 430 miles (700 kilometers) east of Havana. "But what's certain is that there are some who are scared. And when somebody gets diarrhea, they immediately go to the hospital."

The precautions follow last week's announcement of three deaths and 53 diagnosed cases of the waterborne disease, which hadn't been seen in Cuba for many years. Cholera can kill quickly through dehydration but is easily treatable if caught in time. A Health Ministry bulletin said the outbreak was under control.

The government has not responded to requests for comment on reports that several cases have been found in Havana, nor has it followed up last week's announcement with more information, fueling rumors and contradictory stories.

Residents of the capital's El Cerro neighborhood told the AP that a father and daughter had been diagnosed with cholera and were being treated at a local hospital, but it was not clear whether they had contracted the disease. The residents spoke on condition of anonymity for fear they would get into trouble for talking to international journalists.

The BBC reported over the weekend that at least one case of cholera had been detected in Havana, without naming its sources. The Miami Herald, quoting an apparent dissident who lives in Granma province, said more than 1,000 people had been sickened. And exile blogs such as Cafe Fuerte have reported additional deaths, citing residents and unnamed officials.

U.S. Rep. Ileana Ros-Lehtinen, a staunchly anti-Castro congresswoman from Florida, accused the Cuban government of withholding information to avoid scaring away tourists.

Amid the uncertainty, there were also reports that airports in southeastern Mexico had issued a medical alert and were screening passengers from Cuba. But Mexican officials denied that.

"There has not been even a single passenger suspected" of carrying cholera, said Luis Vazquez, spokesman for the Yucatan state health agency. "Cuba is a country with a very good epidemiological system. They don't even let (sick) passengers leave."

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 routinely scrutinize every dwelling and other property to eliminate standing water where mosquitoes bearing another tropical disease, dengue, could breed.

The country also has battalions 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.

The Manzanillo outbreak happened in poor outlying neighborhoods that rely on wells for their water. Cuba's Health Ministry said in its announcement last week that it was collecting samples from the wells, sealing off tainted water supplies and disinfecting hydraulic systems.

Doctors were going door to door to look for people running a fever and to advise residents about preventive measures such as using chlorine drops to disinfect drinking water.

Hotels in Manzanillo were accepting guests as usual, but have ramped up hygienic measures. At the Guacanayabo Hotel everyone was washing their hands and feet in buckets with chlorinated water and the pool was being treated daily.

"There are meetings every day at noon to go over how everything's going, and so far there are no problems here," hotel worker Luleima Ortiz said by phone.

Some people in Havana were also taking precautions.

One man, a barber, said he was washing his hands more often, avoiding touching his mouth at work and boiling his drinking water.

Another, a street vendor, got rid of the cardboard box he had used to hold his sweet pastries, replacing it with a plastic one that's easier to keep clean and does a better job keeping the flies away.

"I, as a vendor, must protect and take care of others," Alfredo Bruceta said.

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