Authorities in eastern Cuba worked to prevent and contain a rare cholera outbreak on Monday, 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. The precautions follow last week's announcement of three deaths and 53 diagnosed cases of the waterborne disease, which had not 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 BBC reported over the weekend that at least one case of cholera had been detected in Havana, without naming its sources.