UK-Research suggests professional drivers more at risk of Legionnaires disease

Windscreen wiper water may be the cause of 20% of cases of Legionnaires'
Disease in England and Wales, the UK Health Protection Agency says. Yet adding
screenwash kills the Legionella bacterium and could save lives, the Agency

It was seen that people who spend a long time driving were at higher risk of
infection: professional drivers are five times more likely to be infected. A
research team of the HPA carried out a questionnaire of people infected. They
found that those most at risk were those who drove or travelled in a van, those
who drove through industrial areas, and those who spent a lot of time in the
car or who often had the car window open. In all they found that the biggest
risk was associated with not adding screenwash to windscreen wiper water, the
European Journal of Epidemiology reports. In a pilot study carried out by the
HPA, traces of Legionella were found in one in five cars that did not have
screenwash, but in no cars that did.

Windscreen wiper fluid without added screenwash in motor vehicles: a newly
identified risk factor for Legionnaires disease is reported in the European
Journal of Epidemiology, Published online: 8 June 2010.

More info - Source: European Agency for Safety and Health at Work