Most deaths from Legionnaires' disease are tied to hospital and nursing home showers, not outdoor cooling towers, new government figures released Thursday show. 

Cooling towers are the focus of an investigation into a Legionnaires' outbreak in New York City this summer that is one of the largest in U.S. history. Twelve people have died.

But the new report shows people can also be exposed to the legionella bacteria through the water that comes out of faucets and bathroom showerheads. The germ spreads into the lungs through water vapor or mist.

"What you hear about is the cooling towers. But the data show there's also risk with drinking water," said Karlyn Beer of the Centers for Disease Control and Prevention. She's the lead author of the new report.

Legionnaires' is a deadly pneumonia that most often strikes the elderly and people with weakened immune systems. An estimated 8,000 to 18,000 people are hospitalized with the disease each year in the U.S. and nearly 100 die from Legionnaries'.

The new statistics are for the years 2011 and 2012. During that time, 14 people died in Legionnaires' outbreaks linked to potable water - showers, most likely. Most occurred in hospitals or nursing homes.

Over the same period, five people died in outbreaks tied to cooling towers and outdoor fountains, and another five couldn't be traced to a specific source.

Overall, illnesses from Legionnaires' are still more commonly linked to outdoor cooling towers and decorative fountains that can spread water vapor over wider areas.