Introduction Rural sanitation deficits in the USA represent an important source of non-point source pollution and may present risks to public health. We propose a controlled, before-and-after (CBA) study using a difference-in-differences analysis to measure the effect of a town-wide sanitation expansion programme on the release of pathogens to the environment.
This work is expected to yield valuable insight into the potential for rural sanitation improvements to reduce pathogen releases and support public health and well-being. Methods We will conduct a CBA study including quantitative measurement of key enteric pathogens and faecal indicator bacteria adjacent to 30 households lacking adequate sanitation.
As households connect to a new sewerage system serving the entire community, longitudinal household sampling will continue until crossover is complete. We will include 10 concurrent control sites with existing appropriate sanitation as well as 10 control sites never receiving the intervention to monitor secular trends in pathogen releases during the study period.
Analysis We will compare the concentration of culturable Escherichia coli in the environment preintervention and postintervention between intervention and control groups.
This protocol describes a controlled, before-and-after evaluation designed to quantify how a community-wide expansion of sewerage affects environmental pathogen release and aspects of household well‑being in a rural Alabama setting.
The investigators frame rural sanitation shortfalls in the USA as a contributor to non-point source pollution and potential public health risk, and propose measuring whether town-level sanitation improvements reduce environmental contamination and associated infection risks.
The study is a controlled, before-and-after (CBA) trial employing a difference-in-differences analytic approach.
Household-level longitudinal sampling will be conducted as dwellings without adequate sanitation are connected to a newly constructed sewerage network that serves the entire community.
Two types of concurrent controls are included: (1) 10 sites with preexisting appropriate sanitation and (2) 10 sites that will not receive the intervention during the study period to capture secular trends.
Environmental sampling will be performed adjacent to 30 households initially lacking adequate sanitation that are scheduled to connect to the new system.
Longitudinal follow-up continues through the crossover period as connections occur.
Control sites supply contemporaneous comparison data to adjust for background temporal changes.
The primary environmental indicator is the concentration of culturable Escherichia coli measured preintervention and postintervention in proximal environmental samples.
The protocol also specifies quantitative measurement of key enteric pathogens and faecal indicator bacteria, although exact pathogen targets and matrices are not detailed in the source text.
Preintervention E.
coli levels will be used to adjust effect estimates for baseline differences between groups.
Analyses will compare changes in culturable E.
coli concentrations between intervention and control groups using a difference-in-differences framework.
Pathogen concentration data will be integrated with quantitative microbial risk assessment methods to estimate potential changes in infection risks across defined exposure pathways.
Details on statistical models, covariates, or sample size calculations were not provided in the source summary.
A parallel pre–post household survey will collect self-reported quality-of-life measures from households that connect to the new sewerage.
Informed consent procedures are specified; participation is voluntary.
Households will receive summaries of their site-specific data, and deidentified aggregate findings will be disseminated at a community forum and through peer-reviewed publication.
The study received IRB approval at the University of North Carolina at Chapel Hill (IRB #24-0665).
Identifiable information will be stored separately and securely.