Windshield Wiper Fluid Harbors Deadly Legionella Bacteria

According to a report published on November 5, 2025, epidemiologist Dr. Alex Sundermann has uncovered a concerning link between windshield wiper fluid and Legionnaires' disease, a severe form of pneumonia.

Dr. Sundermann's research highlights a study that examined windshield wiper fluid in school buses and found that 84% of the buses had high concentrations of Legionella bacteria growing in the fluid. The study also revealed that when the wiper system is activated, the fluid aerosolizes, allowing the bacteria to be easily inhaled and potentially cause Legionnaires' disease.

The epidemiologist also cites a case report describing two truck drivers who developed Legionnaires' disease after exposure to contaminated wiper fluid in their vehicles. Despite searching for other community sources, the researchers could not find an alternative explanation for the drivers' illnesses, leading them to conclude that the wiper fluid was the likely culprit.

To address this issue, Dr. Sundermann recommends using windshield wiper fluids that contain high levels of methanol, which acts as a disinfectant against Legionella bacteria. He cautions against opting for wiper fluids without methanol, as they can actually promote the growth of the harmful bacteria.

This discovery serves as a reminder that infectious diseases can lurk in unexpected places, and taking proactive measures, such as using the right wiper fluid, can help prevent serious health consequences.