The Case for Monitoring for Legionella pneumophila in Drinking Water Distribution Systems

Abstract

As cases of Legionnaires’ disease increase worldwide, there is uncertainty on whether water management plans should focus on the measurement of Legionella species or specifically on L. pneumophila. This paper makes the case that for public water systems and buildings, the target organism should be L. pneumophila, as it is the overwhelming cause of illness, has simple methods for analysis, and remediation procedures avoid unnecessary costs that produce little public health benefit. A review of 930 outbreaks in the United States from 1973 through 2023 showed that there was no public health justification to require public water systems or public buildings (other than healthcare facilities) to monitor or manage for any other species of Legionella other than L. pneumophila.