Project #4721

Methods for Detecting and Differentiating Opportunistic Premise Plumbing Pathogens (OPPPs) to Determine Efficacy of Control and Treatment Technologies

Principal Investigator
Lutgarde Maria
Research Manager
Hyunyoung Jang, PhD
The Regents of the University of Michigan
Microbes & Pathogens
Opportunistic Pathogens


The incidence of waterborne infectious disease outbreaks attributed to opportunistic pathogens (OPs), which are not regulated by the U.S. EPA, appears to be increasing. Although many studies have surveyed premise plumbing and distribution systems for OPs, there is no unified method to monitor drinking water systems for all OPs of interest. This lack of unified methodology stems from differences in life cycle stages and physiologies of different OPs.

This project provides guidance for accurately detecting and quantifying bacterial and protozoan OPs in drinking water systems, with a particular focus on L. pneumophila, P. aeruginosa, nontuberculous mycobacteria, and Acanthamoeba spp.

The research team developed guidelines for utilities with different levels of expertise and resources on how to implement OP monitoring. In addition, the team also examined the effectiveness of several mitigation strategies to reduce the abundance of OPs with a focus on in-home premise plumbing modifications.

Published in 2022.