While the closure of workplaces and public spaces helped flatten the COVID-19 curve, reopening may present a new health risk for returning workers and others—Legionella bacteria.
Back on April 6, Public Services and Procurement Canada
(PSPC) issued a warning to federal government offices about the potential for legionella contamination in any building that goes more than one week with low or no occupancy. In these instances, normal water use may be reduced creating water stagnation and other optimal growth conditions for harmful pathogens such as the legionella bacteria
This same hazard can occur in industrial and other workplaces shuttered during the COVID-19 crisis, where processes using water or water-based fluids (metalworking fluids) have been left to stagnate.
The specific hazard for workers and the public arises when water or water-based fluids contaminated with the legionella bacteria becomes aerosolized
. Those who inhale these tiny airborne droplets or vapour can develop a mild flu-like illness (Pontiac fever) or more severe pneumonia (Legionnaires’ disease).
acquired its name after an outbreak of pneumonia and related symptoms among people attending the 1976 American Legion convention at a hotel in Philadelphia. In total, 34 people died and more than 200 became ill. After an extensive investigation, it was believed the bacteria likely thrived in the cooling towers of the building, became aerosolized and spread through the air conditioning system.
Almost 50 years later the legionella bacteria remains a workplace and public health concern. According to Public Health Ontario
, there were 332 confirmed cases of Legionnaires’ disease or Pontiac fever in 2018, including 22 deaths
. This number of cases is a continuation of an upward trend over the previous five years. Even this though represents just the tip of iceberg as the illness is often misdiagnosed as the flu or pneumonia of undetermined origin. In fact, the U.S. National Academies of Sciences, Engineering, and Medicine
estimates an incidence rate eight to 10 times higher
than the number of reported cases.
Preventive steps critical
Many are concerned now as governments loosen occupancy restrictions in workplaces and public spaces all but shuttered during the initial stages of the COVID-19 crisis. Employers (along with landlords and building management) will want to consider their legal obligation to protect workers
and the public from the legionella bacteria (in addition to the COVID-19 virus).
The same Canadian government agency (PSPC) who warned of the potential for legionella earlier this year, also issued a range of minimum safety directives,
including thoroughly flushing water systems for at least 30 minutes prior to re-occupation of any building going more than one week with no or low occupancy. The directive also noted the need to flush all water fixtures connected to the water system including faucets and water coolers. They also advised those in leased buildings to reach out to landlords to ensure prevention measures are implemented before re-occupancy.
The U.S. Centers for Disease Control and Prevention
(CDC) also weighed in reminding employers or landlords that “water systems be safe to use after a prolonged shutdown to minimize the risk of Legionnaires’ disease and other diseases associated with water.” They outlined eight steps to minimize the potential hazard beginning with the development and implementation of a comprehensive water management program
(WMP) to assess, clean, disinfect, flush, and maintain systems prior to resuming operations.
WHSC legionella resource
WHSC has also recently published
an updated Legionella fact sheet
offering critical insight into the growth and transmission of this potentially deadly bacteria. Also shared are essential elements of water, HVAC and metalworking fluids management programs. This should include monitoring for legionella and training all workplace parties, including joint health and safety committee members and worker health and safety representatives responsible to perform monthly inspections amongst other vital duties.
WHSC virtual COVID-19 training and resources
WHSC remains a leader in COVID-19 Training
and other virtual health and safety training. We also continue to host webinars
and publish COVID-19 resources
during these unprecedented and challenging times
to help ensure workers, supervisors, joint health and safety committee members and others have access to a trusted source of information. Follow us too on social media sites
. There we share news and insights daily.
As Ontario’s only designated health and safety training centre
, WHSC supports workers, their representatives, supervisors, contractors and employers in every work sector with comprehensive training programs
and information services
. In all we do, we put workers first. After all, it is their lives and livelihoods that are affected most when workplace hazards, including the COVID-19 virus and the legionella bacteria, go uncontrolled.
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