Through the Legionella Looking Glass – Part 2: A Look at Current Practices and State of the Science

In the April issue of the Healthy Indoors, Dr. J. David Krause, a senior toxicologist and Associate of a Florida-based health sciences firm, discusses complex public health issues involving Legionnaires’ disease.  Topics in his thorough and well-thought article include:

• Difficulties with tracking Legionnaires’ disease outbreaks
• Limits of public health agencies such as local and state health departments and the Centers for Disease Control and Prevention (CDC)
• Efficacy and accuracy of testing methods for the different strains of Legionella bacteria which cause Legionnaires’ disease
• Legionnaires’ disease as an under diagnosed and under reported illness
• Relying on surveillance is difficult when the disease is under reported and under diagnosed.  Also, current practices do not always include water system testing or treatment for some facilities.
• Difficulties for public health organizations to take a global approach to control, investigation, and prevention of Legionnaires’ disease.

Currently, there are many inconsistencies regarding Legionella.  For example, “municipal water systems have specific bacterial testing requirements, but Legionella is not among them.  The non-regulatory ‘maximum contaminant level goal’ (MCLG) established by the US EPA for Legionella is zero, but testing for Legionella by municipal water suppliers and achieving this goal is not required.”

This is especially troubling considering a study that was recently published in Environmental Science & Technology, which reported that Legionella pneumophila serogroup 1 (LP1) was found in “nearly half of cold water tap samples taken from 68 different water supplies across the United States.”

To read Dr. Krause’s full article, please click here.