The cases of Legionnaires Disease in the Quebec City region have climbed to 173.

It stood at 169 yesterday.

Eleven people have died so far of the disease.

They were exposed to it two weeks before. The incubation period is between 2 to 10 days; symptoms only show up 10 or 15 days after contact.

The source is believed to be the cooling systems of two building towers, where the deadly bacteria grow in stagnant water.

Local authorities have cleaned out the systems in over 100 buildings in the Quebec City area.

The Quebec government called a public inquiry into the outbreak that began in mid-July last week.