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This pathogen lies in wait until the lockdown ends
Once gyms and businesses reopen, people may use water that has been stagnant for weeks. It is a perfect breeding ground for Legionella, a group of bacteria that includes the pathogens that cause Legionnaires’ disease.
Legionnaires’ disease acquired its name in 1976 after an outbreak of pneumonia occurred among veterans that had attended the American Legion convention at a hotel in Philadelphia.
Fortunately Legionnaires’ disease is not transmissible between humans and most of those exposed do not become ill. Legionella travels through droplets and infects the lungs. It causes flu- or cold-like symptoms that may be overlooked. The first symptoms typically occur 5 to 6 days after exposure, or up to 20 days in some cases.
Legionella bacteria occur in water and soil where they are common in small quantities and generally cause little trouble for humans. They can become dangerous when they multiply in stagnant water with temperatures between 20 and 50°C.
Sources of infection
Cooling towers form a major risk due to their widespread distribution of water droplets. From one case in France in 2004, experts learned that infections can occur as far as 6 km away. In 2019, during another outbreak near a cooling tower of a paper mill in Belgium, 30 people…
