Legionnaires' disease was discovered 50 years ago. Here's what experts say we've learned since then

https://i.cbc.ca/ais/1e597fd5-22c1-476b-8ea6-7659e0873a84,1780675780575/full/max/0/default.jpg?im=Crop%2Crect%3D%280%2C131%2C2464%2C1386%29%3BResize%3D%28620%29" title="A technician holds a culture dish with colonies of legionella in a laboratory at the Water and Environment Department at the Institut Pasteur in Lille, January 5, 2004.

Seven people have died and 57 others have been diagnosed with Legionnaire's disease in northern France.

The bacteria is spread by water droplets and can be fatal in five to 30 percent of cases." width="620" />

The 1976 legionnaires' disease investigation revealed how modernization, through things like HVAC systems, can unintentionally increase the possibility of exposure to environmental pathogens — and how critical it is to widely share public health updates.