As many as 20 percent of cases of Legionnaires Disease in the U.K. & Ireland may be caused by windscreen wiper water according to a new report by the UK Health Protection Agency.

Stagnant warm water is a breeding ground for the bacteria connected to Legionnaires disease. It is possible to contract the disease by inhaling small particles of the contaminated water, but there's no need to worry too much – fortunately this is a rare disease and also it can't be spread from one person to another.

The researchers found that professional drivers are five times more likely to be infected. You are more at risk if you drive a van, drive with your car window down or often drive through industrial areas.

But the group of people at highest risk were actually found to be motorists that don't use windscreen wash in their vehicles. This is because windscreen wash kills the legionella bacterium. As a result, drivers are advised to use screenwash in their wiper water.