QUEBEC CITY - Legionnaire's disease has killed six people in Quebec City and sickened 65 others in what health officials say is the worst outbreak Canada has seen in recent years.

Authorities announced this week that two more people have died from the respiratory infection, caused by bacteria that can spread in ventilation systems.

Legionnaire's disease can cause a severe pneumonia-like condition, a high fever and bloody coughing spells and usually affects those who are middle-aged or older.

There were 16 new reported cases in just one 24-hour period this week, a situation the regional health director, Dr. Francois Desbiens, called worrisome.

"It's an exceptional situation," he told a news conference Thursday.

"People in Saint-Roch and Saint-Sauveur boroughs are worried and for good reason," he added, referring to the two areas where the outbreak is centred.

Quebec City Mayor Regis Labeaume cut short his vacation to address the health crisis.

He told a news conference Friday that he visited rooftop cooling towers and found many to be in "deplorable" and even "catastrophic" condition.

Labeaume demanded the province force all building owners to regularly inspect air conditioning systems, adding that a city ordonnance won't work because the legionella bacterium can travel through the air to neighbouring municipalities.

The mayor also emphasized the importance of preserving and protecting the city's reputation as a business and tourist destination.

"The situation in Quebec is known across the country - this is worrisome," said Labeaume, who offered condolences to the victims.

The mayor's spokesman, Paul-Christian Nolin, said previous administrations failed to follow a 1996 health agency recommendation to set up a mandatory building maintenance protocol.

"It's incredible that this wasn't implemented," said Nolin.
Five specialized teams completed an inspection and disinfection sweep of air-conditioning systems in 28 buildings.

Test results from samples collected in the ducts won't be available for three to four weeks.

Meanwhile, the city has ordered all building owners in affected areas to clean all ventilation systems within seven days.