MS, University of Cincinnati, 2008, Engineering : Environmental Engineering

Water utilities need to include the costs of waterborne disease and how much consumers would be willing to pay to prevent them when making cost-benefit decisions about proposed municipal water system improvements. Two Markov Chain Monte Carlo models were developed to estimate the severity and duration of illness and resultant costs of Salmonella outbreaks. Transition probabilities were estimated by conducting a meta-analysis of disease severity. 26.4% of salmonellosis patients see a physician. 12.5% of patients who see a physician are hospitalized, and 3.2% of hospitalized patients die. For patients in nursing homes infected with Salmonella, 10.6% of all patients were hospitalized and 31.1% of hospitalized patients died. Estimates of medical costs were obtained from reported physician charges, medication costs and hospitalization charges. Productivity losses due to Salmonella illnesses were calculated from median household income and the duration of illness determined by the model. Surveys of consumer willingness to pay for quality-adjusted life years and mortality reductions were used to estimate the cost of premature death. These models were then tested against the study of the 1993 Salmonella typhimurium outbreak in Gideon, Missouri by Angulo et al. (1997). For 131 patients in the study, the models predicted 94-97 would recover on their own, 30-33 would recover after seeing a physician, 4-5 would see a physician, and 0.14-0.18 patients would die. These results match those found by the Angulo et al. The models were then used to calculate a cumulative probability distribution of possible costs of the Gideon outbreak. For the reported 7 deaths among 650 cases, the model predicts an economic cost of $31.9 to $32.3 million.

Committee: Steven Buchberger PhD (Committee Chair); Robert Clark PhD (Committee Member); Margaret Kupferle PhD (Committee Member); Regan Murray PhD (Committee Member); Paul Succop PhD (Committee Member) Subjects: Civil Engineering; Environmental Engineering; Epidemiology; Public Health

Doctor of Philosophy, The Ohio State University, 2012, Veterinary Preventive Medicine

Water related disease outbreaks threaten public health and safety worldwide. In the United Sates, notwithstanding public drinking water systems strictly regulated, acute gastrointestinal illnesses (AGI) are continuously reported to health agencies . In agricultural intensive areas, surface and ground water resources are more likely to be exposed to be contaminated with zoonotic bacteria, given the close proximity to sources of feces from livestock, dairy farms and wildlife. The aim of this dissertation was to determine a role of drinking and irrigation water as a vehicle for the transmission of zoonotic bacteria of fecal origin and the need of risk management in rural areas. First, we investigated the microbial quality of private well drinking water system located in six Townships in northeastern Ohio, regions with high concentration of dairy farms. Water samples were collected in 180 households (summer, 2009) and processed to detect fecal indicative organisms, E. coli O157 and Campylobacter jejuni by using commercial MPN methods and quantitative PCR analysis. Around 46%, 9 % and 4% of wells were contaminated with coliforms, E. coli and E. coli O157 respectively. There were no positives for C. jejuni. Second, current guidelines for microbial irrigation water quality recommended by relevant agencies were evaluated in the regard with their practicality and feasibility to detect water quality deterioration in practical applications. Water samples (n=227) were collected in six surface water sources providing irrigation water to each six farm located in Northeastern Ohio over one irrigation season (Apr to Nov ,2010). Bootstrap analysis was applied to estimate optimal water testing frequency compared to those in current guidelines based on the value of fecal indicators detected in the water samples. Current guidelines for microbial quality of irrigation water imprecisely reflected the quality of water over one irrigation season in the context of sampling frequency recom (open full item for complete abstract)

Committee: Jeffrey LeJeune PhD (Advisor); Gireesh Rajashekara PhD (Committee Member); Rebecca Garabed PhD (Committee Member); Song Liang PhD (Committee Member) Subjects: Agriculture; Environmental Health; Environmental Management; Environmental Science; Epidemiology; Microbiology; Molecular Biology; Public Health