An outbreak of Legionnaires' disease in the borough has been traced back to Co-op City. 

The city's Health Department says it has found Legionella bacteria in the water used in the cooling tower at the RiverBay power plant. The department has not confirmed if the towers are the cause of any reported cases of the disease. They only confirmed that eight of the twelve Legionnaires' disease cases in December have been diagnosed amongst Co-op City residents.

The RiverBay Corporation, which operates the cooling towers, has taken immediate steps to decontaminate. Health officials add that the cooling water is kept separate from drinking, cooking and bathing water. 

Officials say it takes Legionnaires' disease between two and 10 days to develop after exposure to the bacteria. Some of the initial symptoms include headache, muscle pain, chills and a high fever.