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12/10/2021 - Construction Safety & Health Programs

Construction sites include a large number of hazards for workers and those nearby. Safety management at TRC helps to oversee the daily activities that take place around construction projects both ...

Legionella Testing and Legionnaires Disease Prevention

Healthcare facilities can learn more about water management policies, procedures and testing requirements from the Centers for Medicare & Medicaid Services.

How to Respond to Legionella Outbreaks

What should you do if an employee or occupant at your facility is diagnosed with Legionnaires disease or Pontiac Fever? How would you respond? Who should be involved? Remember, a methodical approach is crucial. If there is a confirmed case of Legionnaires disease — or worse, a death — it is critical to have a plan that addresses all the issues.

It is best to have a written, well-thought-out plan in advance of any health-related issue; however, with Legionnaires disease it is critical. The critical steps to reduce the potential for additional cases and to respond to the immediate issues include:

  • Shut off drinking water supplies, use bottled water
  • Shutdown outdoor air intakes if there are cooling towers
  • Consult with a physician to assess specific risk factors in other occupants such as the elderly, smokers and immunocompromised
  • Consult with an industrial hygienist with significant expertise in Legionella assessments
  • Industrial hygienists to conduct a walkthrough survey to identify potential Legionella bacteria reservoirs and pathways for potential exposure
  • Develop a sampling plan and collect water samples for Legionella analysis using Polymerase Chain Reaction (PCR) and culturable methodologies
  • Address human resource needs and facility-related issues
  • Evaluate hot water temperatures
  • Evaluate current treatment and maintenance procedures for cooling towers and water distribution and storage systems
  • Industrial hygienist to review laboratory data with medical and facilities components
  • Design and implement treatment options based on laboratory results and water sources found to be positive with the Legionella bacteria
  • Conduct follow-up sampling after treatment and any plumbing modifications
  • Develop a Legionella Control Plan
  • Conduct annual audits of the Plans effectiveness.

Here are a few facts worth remembering:

  1. Legionella pneumophila accounts for 80% of Legionnaire disease cases
  2. Up to 18,000 cases of Legionnaires' disease are documented annually
  3. Inhalation is the primary route of exposure
  4. Legionellosis is not passed from one person to another
  5. The Legionella bacteria is naturally occurring and can be found in outdoor water sources
  6. The Legionella bacteria grow best in warm water, typically 95 to 110oF
  7. One colony of Legionella pneumophila in a drinking water system is a concern
  8. There is no validated air sampling method for the Legionella bacteria
  9. Treatment of water systems is not always effective due to slime layers, corrosion and sediment.

Prevent Legionnaires Disease With Proper Testing

The analytical methods for quantifying/quantitating the concentration of Legionella bacteria in a sample of water include direct fluorescent antibody (DFA), polymerase chain reaction (PCR) and culturable analysis. The culturable analysis will provide a quantitative concentration, the species and serotyping of the Legionella bacteria. Serotyping is critical to making a connection between a source and an individual with the disease.

Remember, Legionella outbreaks can be prevented with the development and implementation of an effective Legionella Control Plan.

Need more information, or a proposal? Please contact Harry M. Neill, CIH at 610-524-5525, ext 15.

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