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Angela Harris

Asst Professor

Mann Hall 208


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Date: 03/04/22 - 3/04/25
Amount: $290,783.00
Funding Agencies: US Army - Corps of Engineers

The ability to continuously monitor fecal bacteria concentrations in nearshore waters through field sensing has the potential to transform the way in which bacteria-driven public health risks are anticipated, mitigated, and managed by allowing for near real-time detection and the creation of high-quality datasets from which forecast models can be developed. Advances in freshwater monitoring reveal that fecal contamination can be predicted using data collected via high-frequency water quality sondes, but additional research is needed to extend these frameworks to coastal waters. We propose to observe water quality conditions every 15 minutes in Bald Head Creek, North Carolina, a tributary of the Cape Fear River, using a multiparameter sonde (YSI EXO2). The sonde will include sensors to monitor conductivity, temperature, dissolved oxygen, pH, turbidity, total algae (phycocyanin, phycoerythrin, and chlorophyll), fluorescent dissolved organic matter, tryptophan-like fluorescence, and water depth. In addition to observing water quality variables, we will analyze creek water samples for fecal indicator bacteria, antibiotic resistant bacteria, amino acids, and particulate and dissolved organic carbon isotopic signatures across four intensive field campaigns. Data collected via this project will be used to develop an innovative observation and machine learning modeling framework for predicting fecal contamination at high frequencies. Insights gained through the project will be shared with local and federal partners (e.g., Village of Bald Head Island, NC Coastal Federation, FDA Division of Seafood Science).

Date: 05/01/20 - 4/30/23
Amount: $85,139.00
Funding Agencies: National Science Foundation (NSF)

Social scientists have turned to phenomenological, subjective measures of resource insecurity and have cogently demonstrated importance of water insecurity in predicting psycho-emotional and physical health outcomes (Hadley and Wutich 2009; Stevenson et al. 2012; Workman and Urkesoy 2017; Wutich 2006; Wutich and Ragsdale 2008). However, there remains a need to compare these experiential subjective measures with objective measures of water scarcity to better understand the predictive capacity of each and to fully understand the interrelationship between co-occurring stressors. This proposed research combines ethnographic methods with anthropometric assessments and quantitative measures of household water and food insecurity and community-level hydrological data. The objectives of this research are four-fold, Objective 1: ethnographically explore the lived experience of water insecurity in Morogoro, Tanzania, Objective 2: compare objective and subjective measures of water insecurity to understand how these factors predict psycho-emotional and physical health outcomes, Objective 3: assess syndemicity of water insecurity, Objective 4: synthesize political ecology and syndemic theory to expand our understanding and measurement of complex social phenomena.

Date: 12/01/20 - 12/01/22
Amount: $134,795.00
Funding Agencies: National Pork Board

All livestock operations generate fecal waste and manure management is an essential aspect of pork production. Regulations mandate permitting, training, design specifications, soil testing and livestock operation stream vegetation buffers. As the scale of pork production has increased to meet consumer demand communities have heightened their concern about the environmental impact of pork operations. Pork producers are actively working to reduce their overall water usage, land use and the carbon foot-print of their farming operations. Responsible environmental farm management has become an inherent necessity to maintain the sustainability of the pork industry and pork producers in the US have affirmed their obligation to safeguard our natural resources and manage pork production operations in a manner that protects natural environments and public health. The proposed studies support environmental management of pork production and address community concerns by facilitating accurate detection and effective attribution of the origin of fecal waste in surface waters and groundwater.

Date: 08/16/21 - 9/30/22
Amount: $800,000.00
Funding Agencies: US Dept. of Treasury

TSA: Environmental Surveillance of Microbial Contaminants

Date: 10/01/21 - 9/30/22
Amount: $57,000.00
Funding Agencies: National Pork Board

Livestock operations generate fecal waste and manure management is an essential aspect of livestock production. Local and state regulations mandate permitting, training, design specifications, and stream vegetation buffers between livestock operations and surface waters. The scale of pork production has increased to meet consumer demand and as production facilities have grown, communities have heightened their concern about the environmental impact of pork operations. Pork producers have worked effectively to reduce their overall water usage, land use, and the carbon footprint of farming operations (National Pork Board, 2018, Thoma et al. 2011). Responsible environmental farm management has become a business necessity for pork producers in the US and producers have affirmed their obligation to manage pork production operations in a manner that protects natural ecosystems and public health. Watersheds, however, generally support multiple types of livestock operations and human dwellings. Each livestock enterprise and residential community is a potential source of fecal waste in surface waters. Fecal waste in surface waters is generally referred to as non-point source contamination. In reality, all fecal waste has a vertebrate animal origin and the species of origin varies with adjacent land-use practices. Monitoring programs established to protect public health have traditionally relied on the culture or detection of fecal coliforms, total coliforms or Enterococcus bacteria in water samples as indicators of fecal contamination in surface waters. These enteric organisms are non-specific indicators of the presence of fecal waste but do not attribute contamination to specific animal hosts. The detection of host-specific enteric organisms, such as Bacteroidales spp. and genetic assays focused on detecting these microbial species have been developed as alternatives to non-host specific indicator organism detection methods (Harwood et al. 2009). All vertebrates release cells from their gastrointestinal tract in their feces. These cells contain mitochondrial DNA (mtDNA), a routine aspect of forensic investigation that can be applied to identify the animal hosts associated with fecal waste (Caldwell et al. 2007). The detection of mtDNA is highly host specific. If mtDNA is detected in a water sample, the vertebrate animal associated with that mtDNA can be determined. Initial studies, however, lacked sensitivity (Caldwell et al. 2009). When we initially developed and tested these assays, at times, fecal waste was present in a stream but not detected. In studies supported by the National Pork Board, we refined these initial mtDNA assays by adapting the use of new Droplet digital PCR technology (BioRad Inc., California, USA), which markedly enhanced the sensitivity of the assay for identifying the presence of host mtDNA in surface waters. New primers and probes were designed, and the assay proved both sensitive and specific. Our studies confirmed the presence of fecal contamination in Stockinghead Creek in Duplin County, NC and documented that the fecal contamination in the creek originates from at least four species, cattle, humans, poultry and swine. This proposal focuses on addressing concerns about the origin of fecal waste in surface waters in other North Carolina livestock intensive watersheds. Specific objectives include: 1) Attributing the source of fecal contamination in NC surface waters in Duplin and Sampson County, NC watersheds ; and 2) Responding to concerns about fecal contamination.

Date: 09/01/21 - 8/31/22
Amount: $60,000.00
Funding Agencies: NCSU Water Resources Research Institute

The Great Coharie River (AKA Great Coharie Creek) is a culturally and environmentally significant water body in Eastern North Carolina. The river has exhibited elevated levels of nutrients and microbial contamination, even after extreme flooding events, and community groups, particularly the Coharie Tribe, are eager to develop a more nuanced understanding of the temporal and spatial dynamics of contamination in the river to ensure human safety during cultural and recreational activities on the river. We propose to conduct high temporal resolution sampling at 4 sites along the river during different seasons and rainfall conditions. Water samples will be analyzed for nutrients, E. coli (fecal indicator bacteria) and source-specific molecular markers of fecal contamination (e.g., human, swine, and poultry). Forecast models will be develop to predict contamination with environmental covariates (e.g., temperature, rainfall, discharge). Working with Coharie Tribe leaders and other community members and applying insights from this research, we will support the development of long-term monitoring plans and decision-making tools for protecting and using the river.

Date: 09/01/20 - 8/31/22
Amount: $414,884.00
Funding Agencies: National Science Foundation (NSF)

Floods impact a series of interconnected urban systems (referred to in this project as the Urban Multiplex) that include the power grid and transportation networks, surface water and groundwater, sewerage and drinking water systems, inland navigation and dams, and other system, all of which are intertwined with the socioeconomic and public health sectors. This project uses a convergent approach to integrate these multiple interconnected systems and merges state-of-the-art practices in hydrologic and hydraulic engineering; systems analysis, optimization and control; machine learning, data and computer science; epidemiology; socioeconomics; and transportation and electrical engineering to develop an Urban Flood Open Knowledge Network (UF-OKN). The UF-OKN will be built by bringing together academic and non-academic researchers from engineering, computer science, social science, and economics. The UF-OKN is envisioned to empower decision makers and the general public by providing information not just on how much flooding may occur from a future event, but also to show the cascading impact of a flood event on natural and engineered infrastructure of an urban area, so that more effective planning and decision-making can occur.

Date: 07/01/21 - 6/30/22
Amount: $750,000.00
Funding Agencies: US Dept. of Health & Human Services (DHHS)

The project is to support the state of North Carolina in surveillance of SARS-CoV-2 variants in the population. We will sequence SARS-CoV-2 from clinical specimens collected as part of the NCSU surveillance lab (surveillance lab director Megan Jacob is a co-PI) and partner WakeMed hospitals. We estimate to sequence 3700 samples over the course of the project.

Date: 07/01/21 - 6/30/22
Amount: $100,000.00
Funding Agencies: NC Department of Health & Human Services (DHHS)

North Carolina (NC) has launched the NC Wastewater Monitoring Network as part of the Centers for Disease Control and Prevention (CDC) National Wastewater Surveillance System (NWSS). This system provides information on the presence and persistence of SARS-CoV-2-like viruses in wastewater systems as a metric of community COVID-19 prevalence. This approach provides a relatively low-cost way to measure both symptomatic and asymptomatic COVID-19 infections in a community-wide sample. Wastewater surveillance can demonstrate trends in COVID-19 prevalence, direct action to protect public health, and allay concerns about the burden of disease when SARS-CoV-2 concentrations are low. The NC Wastewater Monitoring Network builds on an existing collaboration between NCDHHS and the NC Wastewater Pathogen Research Network (NC WW PATH) led by Dr. Rachel Noble in collaboration with University of North Carolina (UNC) system researchers including those from North Carolina State University, UNC Chapel Hill, UNC Charlotte, UNC Wilmington, and East Carolina University. NC WW PATH has developed laboratory methods for measuring the SARS- CoV-2 virus in samples from wastewater treatment plant influent wastewater and primary solids and completed weekly sampling at 20 wastewater treatment plants representative of urban, semi-urban, and rural wastewater sources across nine counties in 2020. NC WW PATH continues to compare wastewater and solids concentrations with data from NCDHHS and other community prevalence studies while applying epidemiological and geospatial tools to develop statewide interactive mapping to better inform public health decisions.

Date: 05/01/21 - 4/30/22
Amount: $10,000.00
Funding Agencies: NCSU Water Resources Research Institute

The prevalence of antibiotic resistance (ABR) bacteria in the environment is alarming, and infections due to these organisms cause more than 2 million illnesses annually in the United States. Surface waters found to be the most common route for the spread of ABR E. coli to humans through recreational activities and irrigation. Extreme weather events (EWE) such as flooding from hurricanes and excessive precipitation preceding outbreaks of contaminants (including ABR E. coli) in receiving waters is a significant threat to human health. Limited work has assessed the impact of poultry CAFOs on microbial water quality in the watersheds of North Carolina and their relation to the presence of ABR bacteria. This study will examine the presence of ABR E .coli in the surface water of two counties (Duplin and Wayne) across the Cape Fear and Neuse River Basin, where the poultry and swine CAFOs are densely built and reported as vulnerable after EWEs. The hypothesis of the study is the prevalence of ABR E .coli in the downstream locations of poultry CAFOs is higher compared to the upstream or where there are no poultry CAFOs. The objective of the study is to identify the primary sources of ABR E .coli in the surface water that is vulnerable to human impact and the effects of climatic events such as rainfall. To accomplish the objective of the study, surface water samples will be collected at multiple sites across several time points surrounding a rainfall event. Samples will be tested for physical, chemical, and microbial water quality. IDEXX Colilert will be used to measure the coliforms and E. coli and ABR E. coli. Microbial source tracking (MST) markers of swine and poultry will be used to identify animal host of fecal contamination via droplet digital PCR (ddPCR), a promising technique that not only detects the targets but also quantifies them precisely in low range. This project will provide the opportunity of using the LA 35 (poultry-specific) fecal marker assay, an assay currently being validated in our lab. Moreover, the correlation among the MST and IDEXX results will provide insight that can inform a strategic plan for reducing health risks associated with surface water contamination.

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