Legionnaires' disease could be rife in your car's windscreen washer bottle if you don't use screenwash, according to new research.
The Health Protection Agency study of 75 patients estimates that the one in five cases of Legionnaires' disease was caused by bacteria breeding in washer reservoirs with no screenwash added.
The research found that Legionella bacteria was found in 20% of cars with no screenwash, but there was no trace in cars with the solution added.
'Not adding screenwash to windscreen wiper fluid is a previously unidentified risk factor and appears to be strongly associated with community-acquired sporadic cases of Legionnaires disease,' the report says.
'A simple recommendation to use screenwash could mitigate transmission of Legionella bacteria to drivers and passengers.'
How to tell if you've got Legionnaire's disease
Legionnaires disease is a rare form of pneumonia caused by the inhalation of Legionella bacteria, which grow in aquatic environments.
It incubates within two to 10 days, but there are cases where symptoms present up to three weeks after exposure.
Symptoms to look out for are flu-like and include muscle aches, tiredness, headaches, dry cough and fever. Sometimes diarrhoea occurs and confusion may develop.
In 2009 there were 345 cases of the disease, which is fatal in 10-15% of instances.