Dispersion of Legionella bacteria in atmosphere: A practical source location estimation method

Area of Science:

• Environmental microbiology
• Epidemiology
• Atmospheric science

Background:

• Legionnaires' disease is a severe pneumonia caused by Legionella bacteria inhalation.
• Contaminated water sources like cooling towers and spa pools can disperse bacteria over long distances.
• Rapid identification and elimination of outbreak sources are crucial for public health.

Purpose of the Study:

• To develop and implement a novel maximum likelihood model for estimating Legionnaires' disease outbreak sources.
• To improve source estimation by incorporating an atmospheric dispersion model for average dose exposure.
• To discuss methods for estimating uncertainty in the model's inferred parameters.

Main Methods:

• Development of a maximum likelihood model utilizing case location data.
• Formulation of the average dose exposure sub-model with an atmospheric dispersion model.
• Application of the model to a real-world outbreak scenario: the 2012 Edinburgh Legionnaires' disease outbreak.

Main Results:

• The model successfully estimated the source of the 2012 Edinburgh Legionnaires' disease outbreak.
• The integration of atmospheric dispersion modeling enhanced the accuracy of source localization.
• The study provides a framework for quantifying uncertainty in source estimation.

Conclusions:

• The developed maximum likelihood model is an effective tool for identifying Legionnaires' disease sources.
• Atmospheric dispersion modeling significantly improves the precision of outbreak source attribution.
• This approach aids in rapid public health interventions to prevent further infections.