Stool-Based Pathogen Detection Offers Advantages as an Outcome Measure for Water, Sanitation, and Hygiene Trials.

Joe Brown,Oliver Cumming

doi:10.4269/ajtmh.19-0639

Abstract

.Most health impact trials of water, sanitation, and hygiene use caregiver-reported diarrhea in children as the primary outcome; this measure is known to be subject to considerable bias, especially when used in unblinded trials. Detection of enteric pathogens in stool or fecal waste via multiplex molecular methods may offer advantages over—and is complementary to—caregiver-reported diarrhea because these measures are objective, on the causal pathway from exposures of interest to disease outcomes, and increasingly feasible in high-burden countries.

Highlights

Detection of enteric pathogens in stool is an objective outcome measurable in either quantal or quantitative multiplex assays and may include viruses, bacteria, protozoa, and helminths of interest
Even in sites where information on the diarrheal disease burden is available, knowledge of potential underlying etiologies of enteric infection and disease remains critically important for the design of interventions to interrupt transmission
Enteric pathogen presence in the gut is a necessary precondition of enteric infection, itself on the causal pathway from primary WASH-related or fecal–oral exposure to WASH-related disease outcomes, notably diarrheal diseases,[3] and various hypothesized sequelae, including environmental enteric dysfunction,[9] adverse growth[10] and cognitive impairment,[11] impacts on the immune system,[12] and poor oral vaccine performance.[13]

Summary

Introduction

Detection of enteric pathogens in stool is an objective outcome measurable in either quantal or quantitative multiplex assays and may include viruses, bacteria, protozoa, and helminths of interest. Such methods are supported by standard, validated procedures used in diagnostic assays, based on wellcharacterized gene targets, offering low detection limits and potential for quantification.[5,6] A range of commercially available kits and custom assays[6,7,8] have enabled simultaneous detection of multiple enteric pathogens via molecular methods, many supported by systematic studies reporting sensitivity and specificity, compared with alternative methods in different populations.

Results

Conclusion