{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/140551"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/140551","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Applications of Wastewater-Based Surveillance Within Rural and Unsewered Communities","abstract":"Wastewater-based surveillance (WBS) presents the opportunity to describe disease and health trends within human populations both more broadly and at a lower cost than clinical reporting. However, rural communities and 'unsewered' households, the latter of which typically treat household wastewater onsite via septic system, remain a barrier to obtaining data that is truly representative of the population. The degree to which resulting data gaps impact WBS datasets has not been explored. Furthermore, these communities, especially when associated with socioeconomic barriers, can be more vulnerable than the general population to the impacts and circulation of infectious disease and antimicrobial resistance (AMR); this makes them key communities for surveillance and intervention. The goal of this research was to explore existing gaps in rural wastewater coverage in surveillance efforts within the context of AMR. This effort aimed both to systematically characterize prior AMR WBS literature for rural and onsite systems and to examine the occurrence of antibiotic resistance genes (ARGs) within septic systems compared with 'standard' untreated sewage collected at the intake to centralized wastewater treatment plants. Review of the existing literature confirmed that rural, small, and onsite wastewater systems were targets for only a small fraction of WBS campaigns, rendering a meta-analysis of their derived data infeasible. Highly recommended WBS techniques, such as longitudinal sampling campaigns or metagenomic sequencing, were particularly rare for rural applications, suggesting a potential gap in the generalizability of data derived from those techniques. Notably, conventional septic systems, which treat the waste of more than a fifth of the U.S. population, were included in only a handful of prior studies targeting AMR. It should be noted that WBS can be integrated with 'treated effluent' sampling for the purposes of environmental surveillance and risk assessment, which are considered key in the surveillance of AMR given its ability to persist and proliferate in natural settings. Given the reliance of septic systems on environmental systems for final treatment and their association with private drinking water resources, this oversight suggests an area of need for research into potential environmental pathways contributing to AMR spread. Septage (a pumpout of the septic tank contents) and septic tank effluent yielded consistent detection rates of ARGs and comparable ARG concentrations when compared with untreated centralized sewage from similar regions. This suggests, in accordance with the limited prior research, that targeted WBS campaigns including septic systems are feasible. Intriguingly, this also suggests that attenuation of some ARGs in the tank may be limited. However, there were noteworthy differences between the matrices, including a lower abundance of blaCTX-M and higher abundance of intI1 within septage and septic effluent samples compared with sewage; the former represents a gene encoding resistance to clinically-important beta lactam antibiotics and the latter acts as an indicator of multi-antibiotic resistance and propensity to mobilize to new bacterial hosts. However, the general similarity may suggest that centralized sewer collection may sufficiently capture unsewered population health in in some cases.","abstract_html":"Wastewater-based surveillance (WBS) presents the opportunity to describe disease and health trends within human populations both more broadly and at a lower cost than clinical reporting. However, rural communities and 'unsewered' households, the latter of which typically treat household wastewater onsite via septic system, remain a barrier to obtaining data that is truly representative of the population. The degree to which resulting data gaps impact WBS datasets has not been explored. Furthermore, these communities, especially when associated with socioeconomic barriers, can be more vulnerable than the general population to the impacts and circulation of infectious disease and antimicrobial resistance (AMR); this makes them key communities for surveillance and intervention. The goal of this research was to explore existing gaps in rural wastewater coverage in surveillance efforts within the context of AMR. This effort aimed both to systematically characterize prior AMR WBS literature for rural and onsite systems and to examine the occurrence of antibiotic resistance genes (ARGs) within septic systems compared with 'standard' untreated sewage collected at the intake to centralized wastewater treatment plants. Review of the existing literature confirmed that rural, small, and onsite wastewater systems were targets for only a small fraction of WBS campaigns, rendering a meta-analysis of their derived data infeasible. Highly recommended WBS techniques, such as longitudinal sampling campaigns or metagenomic sequencing, were particularly rare for rural applications, suggesting a potential gap in the generalizability of data derived from those techniques. Notably, conventional septic systems, which treat the waste of more than a fifth of the U.S. population, were included in only a handful of prior studies targeting AMR. It should be noted that WBS can be integrated with 'treated effluent' sampling for the purposes of environmental surveillance and risk assessment, which are considered key in the surveillance of AMR given its ability to persist and proliferate in natural settings. Given the reliance of septic systems on environmental systems for final treatment and their association with private drinking water resources, this oversight suggests an area of need for research into potential environmental pathways contributing to AMR spread. Septage (a pumpout of the septic tank contents) and septic tank effluent yielded consistent detection rates of ARGs and comparable ARG concentrations when compared with untreated centralized sewage from similar regions. This suggests, in accordance with the limited prior research, that targeted WBS campaigns including septic systems are feasible. Intriguingly, this also suggests that attenuation of some ARGs in the tank may be limited. However, there were noteworthy differences between the matrices, including a lower abundance of blaCTX-M and higher abundance of intI1 within septage and septic effluent samples compared with sewage; the former represents a gene encoding resistance to clinically-important beta lactam antibiotics and the latter acts as an indicator of multi-antibiotic resistance and propensity to mobilize to new bacterial hosts. However, the general similarity may suggest that centralized sewer collection may sufficiently capture unsewered population health in in some cases.","abstract_has_math":false,"creators":["Price, Sarah Fox"],"institution":"Virginia Tech","degree_name":"Doctor of Philosophy","degree_level":"doctoral","degree_discipline":"Biological Systems Engineering","degree_department":"Biological Systems Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":["Krometis, Leigh Anne Henry"],"committee_members":["Pruden-Bagchi, Amy Jill","Brown, Philip James","Cohen, Alasdair Gordon","Czuba, Jonathan A."],"year":2025,"date_issued":"2025-12-22","date_published":"2025-12-22","updated_at":"2026-07-22T22:19:03Z","subjects":["rural health","septic systems","wastewater-based surveillance","antimicrobial resistance","antibiotic resistance"],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:45099"],"render_values":[{"text":"vt_gsexam:45099","href":null,"code":true}]}]},"links":{"outbound_url":"https://hdl.handle.net/10919/140551","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Krometis, Leigh Anne Henry"]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Pruden-Bagchi, Amy Jill","Brown, Philip James","Cohen, Alasdair Gordon","Czuba, Jonathan A."]},{"key":"dc:contributor.department","label":"Department","values":["Biological Systems Engineering"]},{"key":"dc:creator","label":"Author","values":["Price, Sarah Fox"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-12-23T09:01:37Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-12-23T09:01:37Z"]},{"key":"dc:date.issued","label":"Date","values":["2025-12-22"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biological Systems Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["doctoral"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["rural health","septic systems","wastewater-based surveillance","antimicrobial resistance","antibiotic resistance"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:45099"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/10919/140551"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Wastewater-based surveillance (WBS) presents the opportunity to describe disease and health trends within human populations both more broadly and at a lower cost than clinical reporting. However, rural communities and 'unsewered' households, the latter of which typically treat household wastewater onsite via septic system, remain a barrier to obtaining data that is truly representative of the population. The degree to which resulting data gaps impact WBS datasets has not been explored. Furthermore, these communities, especially when associated with socioeconomic barriers, can be more vulnerable than the general population to the impacts and circulation of infectious disease and antimicrobial resistance (AMR); this makes them key communities for surveillance and intervention. The goal of this research was to explore existing gaps in rural wastewater coverage in surveillance efforts within the context of AMR. This effort aimed both to systematically characterize prior AMR WBS literature for rural and onsite systems and to examine the occurrence of antibiotic resistance genes (ARGs) within septic systems compared with 'standard' untreated sewage collected at the intake to centralized wastewater treatment plants. Review of the existing literature confirmed that rural, small, and onsite wastewater systems were targets for only a small fraction of WBS campaigns, rendering a meta-analysis of their derived data infeasible. Highly recommended WBS techniques, such as longitudinal sampling campaigns or metagenomic sequencing, were particularly rare for rural applications, suggesting a potential gap in the generalizability of data derived from those techniques. Notably, conventional septic systems, which treat the waste of more than a fifth of the U.S. population, were included in only a handful of prior studies targeting AMR. It should be noted that WBS can be integrated with 'treated effluent' sampling for the purposes of environmental surveillance and risk assessment, which are considered key in the surveillance of AMR given its ability to persist and proliferate in natural settings. Given the reliance of septic systems on environmental systems for final treatment and their association with private drinking water resources, this oversight suggests an area of need for research into potential environmental pathways contributing to AMR spread. Septage (a pumpout of the septic tank contents) and septic tank effluent yielded consistent detection rates of ARGs and comparable ARG concentrations when compared with untreated centralized sewage from similar regions. This suggests, in accordance with the limited prior research, that targeted WBS campaigns including septic systems are feasible. Intriguingly, this also suggests that attenuation of some ARGs in the tank may be limited. However, there were noteworthy differences between the matrices, including a lower abundance of blaCTX-M and higher abundance of intI1 within septage and septic effluent samples compared with sewage; the former represents a gene encoding resistance to clinically-important beta lactam antibiotics and the latter acts as an indicator of multi-antibiotic resistance and propensity to mobilize to new bacterial hosts. However, the general similarity may suggest that centralized sewer collection may sufficiently capture unsewered population health in in some cases."]},{"key":"dc:description.abstractgeneral","label":"General Abstract","values":["Modern medicine has made significant advancements in treating infectious disease, yet tracking the spread and evolution of diseases through populations – both locally and globally – remains essential for prompt and appropriate medical intervention. Antimicrobial resistance (AMR) is the tendency for germs or disease-causing pathogens to survive antibiotic or antifungal medication, making infectious disease notably more dangerous and challenging to treat. However, clinical data on disease incidence is typically limited to people who have noticeable symptoms, have access to medical care, and choose to get tested. Further, AMR is a particularly challenging target to characterize in the clinical setting as it doesn't correspond to a single germ or gene mechanism. One emerging strategy might allow us to sidestep the biases associated with clinical datasets: infected individuals often shed the germs infecting them in their stool, allowing us to detect and quantify them by sampling and testing municipal sewage. Wastewater-based surveillance (WBS) allows us to see disease trends across a whole population with very few samples, sometimes even before we see those trends in the clinic. However, one of the current concerns with centralized WBS is that rural communities may be an oversight, in part because they have a larger proportion of people using onsite wastewater treatment (i.e., 'unsewered' populations). Clinical data for disease prevalence and AMR patterns are particularly lacking in rural and underserved communities, making them an essential point for intervention. This research aimed to explore the rural/urban research gap and examine one of the most common wastewater systems for unsewered households: septic systems. A systematic literature review of published WBS efforts for AMR showed that rural wastewater treatment systems and septic systems did represent a minority of sampling sites, limiting our ability to compare results across rural and urban contexts. Studies of AMR in conventional septic systems were largely absent, suggesting an oversight in environmental surveillance given the widespread use and direct environmental release from these systems. Field studies examined antibiotic resistance genes (ARGs) within the contents (via pumped out septage) and semi-treated effluent of septic tanks, the first of two stages of treatment within a conventional septic system; both were compared to untreated centralized sewage as a benchmark. Despite the substantially smaller contributing populations and the multi-day detention time of wastewaters within the tank, ARGs and other marker genes were not only consistently present but at relatively similar concentrations in septic samples as in centralized sewage. Although more research is needed within this area, this may indicate that a) WBS may be feasible in septic samples, b) ARGs are not appreciably reduced within the septic tank, and c) given relatively similar results, testing of centralized sewer samples may in many cases be sufficient to capture the health and infection trends of unsewered populations."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Doctor of Philosophy"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["ETD"]},{"key":"dc:title","label":"Title","values":["Applications of Wastewater-Based Surveillance Within Rural and Unsewered Communities"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Krometis, Leigh Anne Henry"],"dc:contributor.committeemember":["Pruden-Bagchi, Amy Jill","Brown, Philip James","Cohen, Alasdair Gordon","Czuba, Jonathan A."],"dc:contributor.department":["Biological Systems Engineering"],"dc:creator":["Price, Sarah Fox"],"dc:date.accessioned":["2025-12-23T09:01:37Z"],"dc:date.available":["2025-12-23T09:01:37Z"],"dc:date.issued":["2025-12-22"],"dc:description.abstract":["Wastewater-based surveillance (WBS) presents the opportunity to describe disease and health trends within human populations both more broadly and at a lower cost than clinical reporting. However, rural communities and 'unsewered' households, the latter of which typically treat household wastewater onsite via septic system, remain a barrier to obtaining data that is truly representative of the population. The degree to which resulting data gaps impact WBS datasets has not been explored. Furthermore, these communities, especially when associated with socioeconomic barriers, can be more vulnerable than the general population to the impacts and circulation of infectious disease and antimicrobial resistance (AMR); this makes them key communities for surveillance and intervention. The goal of this research was to explore existing gaps in rural wastewater coverage in surveillance efforts within the context of AMR. This effort aimed both to systematically characterize prior AMR WBS literature for rural and onsite systems and to examine the occurrence of antibiotic resistance genes (ARGs) within septic systems compared with 'standard' untreated sewage collected at the intake to centralized wastewater treatment plants. Review of the existing literature confirmed that rural, small, and onsite wastewater systems were targets for only a small fraction of WBS campaigns, rendering a meta-analysis of their derived data infeasible. Highly recommended WBS techniques, such as longitudinal sampling campaigns or metagenomic sequencing, were particularly rare for rural applications, suggesting a potential gap in the generalizability of data derived from those techniques. Notably, conventional septic systems, which treat the waste of more than a fifth of the U.S. population, were included in only a handful of prior studies targeting AMR. It should be noted that WBS can be integrated with 'treated effluent' sampling for the purposes of environmental surveillance and risk assessment, which are considered key in the surveillance of AMR given its ability to persist and proliferate in natural settings. Given the reliance of septic systems on environmental systems for final treatment and their association with private drinking water resources, this oversight suggests an area of need for research into potential environmental pathways contributing to AMR spread. Septage (a pumpout of the septic tank contents) and septic tank effluent yielded consistent detection rates of ARGs and comparable ARG concentrations when compared with untreated centralized sewage from similar regions. This suggests, in accordance with the limited prior research, that targeted WBS campaigns including septic systems are feasible. Intriguingly, this also suggests that attenuation of some ARGs in the tank may be limited. However, there were noteworthy differences between the matrices, including a lower abundance of blaCTX-M and higher abundance of intI1 within septage and septic effluent samples compared with sewage; the former represents a gene encoding resistance to clinically-important beta lactam antibiotics and the latter acts as an indicator of multi-antibiotic resistance and propensity to mobilize to new bacterial hosts. However, the general similarity may suggest that centralized sewer collection may sufficiently capture unsewered population health in in some cases."],"dc:description.abstractgeneral":["Modern medicine has made significant advancements in treating infectious disease, yet tracking the spread and evolution of diseases through populations – both locally and globally – remains essential for prompt and appropriate medical intervention. Antimicrobial resistance (AMR) is the tendency for germs or disease-causing pathogens to survive antibiotic or antifungal medication, making infectious disease notably more dangerous and challenging to treat. However, clinical data on disease incidence is typically limited to people who have noticeable symptoms, have access to medical care, and choose to get tested. Further, AMR is a particularly challenging target to characterize in the clinical setting as it doesn't correspond to a single germ or gene mechanism. One emerging strategy might allow us to sidestep the biases associated with clinical datasets: infected individuals often shed the germs infecting them in their stool, allowing us to detect and quantify them by sampling and testing municipal sewage. Wastewater-based surveillance (WBS) allows us to see disease trends across a whole population with very few samples, sometimes even before we see those trends in the clinic. However, one of the current concerns with centralized WBS is that rural communities may be an oversight, in part because they have a larger proportion of people using onsite wastewater treatment (i.e., 'unsewered' populations). Clinical data for disease prevalence and AMR patterns are particularly lacking in rural and underserved communities, making them an essential point for intervention. This research aimed to explore the rural/urban research gap and examine one of the most common wastewater systems for unsewered households: septic systems. A systematic literature review of published WBS efforts for AMR showed that rural wastewater treatment systems and septic systems did represent a minority of sampling sites, limiting our ability to compare results across rural and urban contexts. Studies of AMR in conventional septic systems were largely absent, suggesting an oversight in environmental surveillance given the widespread use and direct environmental release from these systems. Field studies examined antibiotic resistance genes (ARGs) within the contents (via pumped out septage) and semi-treated effluent of septic tanks, the first of two stages of treatment within a conventional septic system; both were compared to untreated centralized sewage as a benchmark. Despite the substantially smaller contributing populations and the multi-day detention time of wastewaters within the tank, ARGs and other marker genes were not only consistently present but at relatively similar concentrations in septic samples as in centralized sewage. Although more research is needed within this area, this may indicate that a) WBS may be feasible in septic samples, b) ARGs are not appreciably reduced within the septic tank, and c) given relatively similar results, testing of centralized sewer samples may in many cases be sufficient to capture the health and infection trends of unsewered populations."],"dc:description.degree":["Doctor of Philosophy"],"dc:format.medium":["ETD"],"dc:identifier.other":["vt_gsexam:45099"],"dc:identifier.uri":["https://hdl.handle.net/10919/140551"],"dc:language.iso":["en"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["rural health","septic systems","wastewater-based surveillance","antimicrobial resistance","antibiotic resistance"],"dc:title":["Applications of Wastewater-Based Surveillance Within Rural and Unsewered Communities"],"dc:type":["Dissertation"],"thesis:degree_discipline":["Biological Systems Engineering"],"thesis:degree_level":["doctoral"],"thesis:degree_name":["Doctor of Philosophy"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:03Z"}