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Health officials scramble to contain Legionnaires' outbreak in Quebec

Quebec City is coming to grips with the worst outbreak of Legionnaires' disease in the country in recent years, which has killed six people and contaminated 65 others.

Public health officials are scrambling to eradicate the cause of the outbreak believed to be spreading because of faulty or contaminated air conditioning systems located on the roofs of buildings.

Tiny droplets of contaminated water from the cooling towers of air conditioning systems were believed to have spread across a wide section of the city. Health authorities have proceeded with the disinfection of 62 cooling towers in the hopes of containing the spread of the disease.

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Legionnaires' disease, or legionella, is a deadly form of pneumonia and presents symptoms similar to the flu. The number of cases increased dramatically in recent days to 62 yesterday from 49 at the beginning of the week. Local officials believe it is one of the worst outbreaks of the disease since legionella was first reported in the United States in the 1970s.

The head of the regional public health board, Dr. François Desbiens, believes that more cases will likely be reported in the coming days. He said the incubation period for Legionnaires' disease varies anywhere between two to ten days.

"We are quite concerned with this outbreak. New cases are being reported every day. We are doing everything we can to stop it as fast we can," Dr. Desbiens said in a news conference on Thursday.

Signs of the disease were first reported at the beginning of the month. As the number of cases increased, public health officials struggled to identify the source or sources of contamination. However, neither the city nor the province had a registry of the locations of the cooling towers on all the building. Officials had to fly over the city's downtown core to locate the cooling towers.

Dr. Desbiens said changes to current regulations were urgently needed that would require the owners of the building to decontaminate their water cooling towers on a regular basis and that the locations of all the cooling towers be listed in a provincial or regional registry.

Officials said that they will not be able to say conclusively for another four weeks whether the decontaminations measures will have completely eliminated the cause of the outbreak.

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