An unintended workplace health threat resulting from the fight against COVID-19 could be lurking in an employer’s water system—Legionella, the bacteria that causes Legionnaires’ disease. As state and local governments begin lifting safe-at-home orders, employers and building owners will be restarting operations and reopening buildings (or parts of buildings) that may have been unoccupied for weeks. Many such operations include water supply systems that have also been shut down during the business closings. These dormant water systems and devices can lead to an increased exposure to Legionella for several reasons, including a lack of water circulation and a temporary cessation of water treatment and water quality monitoring programs. In anticipation of the large number of workplaces and other buildings that will be reopening in the near future, the U.S. Centers for Disease Control and Prevention (CDC) recently updated its guidance for reducing Legionella risks in building water systems.
