Windshield Washer Fluid a Source of Legionnaires (ASMevents, American Society for Microbiology, May 19, 2014)
Also discussed here: Windshield washer fluid a source of Legionnaires: Found in most school buses (ScienceDaily, May 18, 2014)
Today we review research by Otto Schwake who established a link between windshield washer fluid and Legionnaires’ disease, a severe form of pneumonia. The link is a bacteria, Legionella, found in the fluid which is transmitted to humans in the mist that is formed when sprayed on the windshield and then inhaled. The bacteria can also cause Pontiac fever, a milder illness resembling the flu. More bacteria were found in summer than in winter and in 75% of the washer fluid samples taken from school buses in Arizona. Although most people exposed to this threat do not become sick, seniors and smokers are at most risk. As much as 20% of those affected by Legionnaires’ disease in the UK, outside of those in hospitals, was found to be associated with automobile windshield washer fluid. One more reason to reduce the number of cars on the road and the pollution they cause.
"Washer fluid spray can release potentially dangerous numbers of these bacteria into the air. These results suggest that automobiles may serve as a source of transmission for Legionella infections,"
“Legionella are bacteria that are found naturally in the environment, usually in water. They are commonly associated with the cooling towers found in large-scale air conditioners and hot tubs. They are not spread from person to person but instead are transmitted via mist or vapor containing the bacteria”
“the bacterial concentrations increased over time and they were able to maintain stable populations for up to 14 months. In the second study, they tested the washer fluid from school buses in central Arizona and found culturable Legionella in approximately 75% of the samples”
"One such study attributed nearly 20 percent of Legionnaires' disease cases in the United Kingdom not associated with hospitals or outbreaks to automobile windshield washer fluid.”
“Most of the people exposed don’t become sick…Those most at risk include the elderly, smokers and those with weakened immune systems”
“Washer fluid has the traits a potentially dangerous source of Legionella exposure needs…It is aerosolized, heated and people are regularly exposed to it. The results from this study support previously demonstrated epidemiological evidence for a link between automobiles and Legionnaires’ disease by providing microbiological data on survival, presence and transmission of Legionella in washer fluid.”
"While potential transmission of a deadly respiratory disease from a source as common as automobile windshield washing systems is significant, the study also points to the fact people can be exposed to pathogens -- particularly those occurring naturally in the environment -- in previously unknown and unusual ways."