IEUBK Modeling of Children's Blood Lead Levels in Homes Served by Private Domestic Wells in Three Illinois Counties.

Lead is known to impair neurocognitive development in children. Drinking water is routinely monitored for lead content in municipal systems, but private well owners are not required to test for lead. The lack of testing poses a risk of lead exposure and resulting health effects to rural children. In three Illinois counties, we conducted a cross-sectional study (n = 151 homes) examining water lead levels (WLLs), water consumption, and water treatment status to assess risk of lead exposure among residents using private water wells. Since blood lead levels (BLLs) were not available, EPA's Integrated Exposure Uptake Biokinetic (IEUBK) modeling was used to estimate the incremental contribution of WLL to BLL, holding all other sources of lead at their default values. Nearly half (48.3%) of stagnant water samples contained measurable lead ranging from 0.79 to 76.2 µg/L (median= 0.537 µg/L). IEUBK modeling showed BLLs rose from 0.3 to 0.4 µg/dL when WLLs rose from 0.54 µg/L (the tenth percentile) to 4.88 µg/L (the 90th percentile). Based on IEUBK modeling, 18% of children with a WLL at the 10th percentile would have a BLL above 3.5 µg/dL compared to 27.4% of those with a WLL at the 90th percentile. These findings suggest that the consumption of unfiltered well water likely results in increased blood lead levels in children.

A Framework for Evaluating Local Adaptive Capacity to Health Impacts of Climate Change: Use of Kenya's County-Level Integrated Development Plans.

Background: Health National Adaptation Plans were developed to increase the capacity of low- and middle-income countries (LMICs) to adapt to the impacts of climate change on the health sector. Climate and its health impacts vary locally, yet frameworks for evaluating the adaptive capacity of health systems on the subnational scale are lacking. In Kenya, counties prepare county integrated development plans (CIDPs), which contain information that might support evaluations of the extent to which counties are planning climate change adaptation for health. Objectives: To develop and apply a framework for evaluating CIDPs to assess the extent to which Kenya's counties are addressing the health sector's adaptive capacity to climate change. Methods: CIDPs were analyzed based on the extent to which they addressed climate change in their description of county health status, whether health is noted in their descriptions of climate change, and whether they mention plans for developing climate and health programs. Based on these and other data points, composite climate and health adaptation (CHA) scores were calculated. Associations between CHA scores and poverty rates were analyzed. Findings: CHA scores varied widely and were not associated with county-level poverty. Nearly all CIDPs noted climate change, approximately half mentioned health in the context of climate change and only 16 (34%) noted one or more specific climate-sensitive health conditions. Twelve (25%) had plans for a sub-program in both adaptive capacity and environmental health. Among the 24 counties with plans to develop climate-related programs in health programs, all specified capacity building, and 20% specified integrating health into disaster risk reduction. Conclusion: Analyses of county planning documents provide insights into the extent to which the impacts of climate change on health are being addressed at the subnational level in Kenya. This approach may support governments elsewhere in evaluating climate change adaptation for health by subnational governments.

Repeated home drinking water sampling to improve detection of particulate lead spikes: a simulation study.

BACKGROUND: Lead can be present in drinking water in soluble and particulate forms. The intermittent release of lead particulates in drinking water can produce highly variable water lead levels (WLLs) in individual homes, a health concern because both particulate and soluble lead are bioavailable. More frequent water sampling would increase the likelihood of identifying sporadic lead "spikes," though little information is available to aid in estimating how many samples are needed to achieve a given degree of sensitivity to spike detection. OBJECTIVE: To estimate the number of rounds of tap water sampling needed to determine with a given level of confidence that an individual household is at low risk for the intermittent release of lead particulates. METHODS: We simulated WLLs for 100,000 homes on 15 rounds of sampling under a variety of assumptions about lead spike release. A Markovian structure was used to describe WLLs for individual homes on subsequent rounds of sampling given a set of transitional probabilities, in which homes with higher WLLs at baseline were more likely to exhibit a spike on repeated sampling. RESULTS: Assuming 2% of homes had a spike on the first round of sampling and a mid-range estimate of transitional probabilities, the initial round of sampling had a 6.4% sensitivity to detect a spike. Seven rounds of sampling would be needed to increase the sensitivity to 50%, which would leave unrecognized the more than 15,000 homes that intermittently exhibit spikes. SIGNIFICANCE: For assessing household risk for lead exposure through drinking water, multiple rounds of water sampling are needed to detect the infrequent but high spikes in WLLs due to particulate release. Water sampling procedures for assessment of lead exposure in individual homes should be modified to account for the infrequent but high spikes in WLL. IMPACT: It has been known for decades that intermittent "spikes" in water lead occur due to the sporadic release of lead particulates. However, conventional water sampling strategies do not account for these infrequent but hazardous events. This research suggests that current approaches to sampling tap water for lead testing identify only a small fraction of homes in which particulate spikes occur, and that sampling procedures should be changed substantially to increase the probability of identifying the hazard of particulate lead release into drinking water.

Prevalence and predictors of chronic kidney disease of undetermined causes (CKDu) in Western Kenya's "sugar belt": a cross-sectional study.

BACKGROUND: Epidemics of chronic kidney disease of undetermined causes (CKDu) among young male agricultural workers have been observed in many tropical regions. Western Kenya has similar climatic and occupational characteristics as many of those areas. The study objectives were to characterize prevalence and predictors of CKDu, such as, HIV, a known cause of CKD, in a sugarcane growing region of Kenya; and to estimate prevalence of CKDu across occupational categories and evaluate if physically demanding work or sugarcane work are associated with reduced eGFR. METHODS: The Disadvantaged Populations eGFR Epidemiology Study (DEGREE) protocol was followed in a cross-sectional study conducted in Kisumu County, Western Kenya. Multivariate logistic regression was performed to identify predictors of reduced eGFR. RESULTS: Among 782 adults the prevalence of eGFR < 90 was 9.85%. Among the 612 participants without diabetes, hypertension, and heavy proteinuria the prevalence of eGFR < 90 was 8.99% (95%CI 6.8%, 11.5%) and 0.33% (95%CI 0.04%, 1.2%) had eGFR < 60. Among the 508 participants without known risk factors for reduced eGFR (including HIV), the prevalence of eGFR < 90 was 5.12% (95%CI 3.4%, 7.4%); none had eGFR < 60. Significant risk factors for reduced eGFR were sublocation, age, body mass index, and HIV. No association was found between reduced eGFR and work in the sugarcane industry, as a cane cutter, or in physically demanding occupations. CONCLUSION: CKDu is not a common public health problem in this population, and possibly this region. We recommend that future studies should consider HIV to be a known cause of reduced eGFR. Factors other than equatorial climate and work in agriculture may be important determinants of CKDu epidemics.

A Web-Based Interactive Map to Promote Health-Care Facility Flood Preparedness.

OBJECTIVES: Little is known about how flood risk of health-care facilities (HCFs) is evaluated by emergency preparedness professionals and HCFs administrators. This study assessed knowledge of emergency preparedness and HCF management professionals regarding locations of floodplains in relation to HCFs. A Web-based interactive map of floodplains and HCF was developed and users of the map were asked to evaluate it. METHODS: An online survey was completed by administrators of HCFs and public health emergency preparedness professionals in Illinois, before and after an interactive online map of floodplains and HCFs was provided. RESULTS: Forty Illinois HCFs located in floodplains were identified, including 12 long-term care facilities. Preparedness professionals have limited knowledge of whether local HCFs were in floodplains, and few reported availability of geographic information system (GIS) resources at baseline. Respondents intended to use the interactive map for planning and stakeholder communications. CONCLUSIONS: Given that HCFs are located in floodplains, this first assessment of using interactive maps of floodplains and HCFs may promote a shift to reliable data sources of floodplain locations in relation to HCFs. Similar approaches may be useful in other settings.

Predictors of Water Lead Levels in Drinking Water of Homes With Domestic Wells in 3 Illinois Counties.

CONTEXT: Millions of US homes receive water from private wells, which are not required to be tested for lead (Pb). An approach to prioritizing high-risk homes for water lead level (WLL) testing may help focus outreach and screening efforts, while reducing the testing of homes at low risk. OBJECTIVE: To (1) characterize distribution of WLLs and corrosivity in tap water of homes with private residential wells, and (2) develop and evaluate a screening strategy for predicting Pb detection within a home. DESIGN: Cross-sectional. SETTING: Three Illinois counties: Kane (northern), Peoria (central), and Jackson (southern). PARTICIPANTS: 151 private well users from 3 Illinois counties. INTERVENTION: Water samples were analyzed for WLL and corrosivity. MAIN OUTCOME MEASURES: (1) WLL and corrosivity, and (2) the sensitivity, specificity, and predictive value of a strategy for prioritizing homes for WLL testing. RESULTS: Pb was detected (>0.76 ppb) in tap water of 48.3% homes, and 3.3% exceeded 15 ppb, the US Environmental Protection Agency action level for community water systems. Compared with homes built in/after 1987 with relatively low corrosivity, older homes with more corrosive water were far more likely to contain measurable Pb (odds ratio = 11.07; 95% confidence interval, 3.47-35.31). The strategy for screening homes with private wells for WLL had a sensitivity of 88%, specificity of 42%, positive predictive value of 58%, and negative predictive value of 80%. CONCLUSIONS: Pb in residential well water is widespread. The screening strategy for prioritizing homes with private wells for WLL testing is greater than 85% sensitive.

Decentralized solar-powered drinking water ozonation in Western Kenya: an evaluation of disinfection efficacy.

Background: Decentralized drinking water treatment methods generally apply membrane-based treatment approaches. Ozonation of drinking water, which previously has only been possible at large centralized facilities, can now be accomplished on a small-scale using microplasma technology. The efficacy of decentralized solar-powered ozonation for drinking water treatment is not known. Methods: We established a 1,000L decentralized solar-powered water treatment system located in Kisumu County, Kenya. Highly contaminated surface water is pumped to the treatment system, which includes flocculation and filtration steps prior to ozonation. Turbidity, total coliform bacteria, and E. coli were measured at various stages of water treatment, and bacterial log reduction values (LRVs) were calculated. Results: Nine trials were conducted treating 1000L of water in three hours. Baseline turbidity and E. coli concentrations were reduced from a median of 238 nephelometric turbidity units (NTU) and 2,752 most probable number/100mL, respectively, in surface water to 1.0 NTU and undetectable E. coli per100mL in finished drinking water. The nine trials yielded a mean E. coli LRV of 3.36 (2.71-4.00, 95% CI). Conclusions: Based on the observed reduction of E. coli, the solar-powered system shows promise as a means for producing safe drinking water. Further research is needed to characterize limitations, scalability, economic viability, and community perspectives that could help determine the role for similar systems in other settings.

Fecal pollution source characterization at non-point source impacted beaches under dry and wet weather conditions.

Though Lake Michigan beaches in Chicago are not impacted by stormwater or wastewater outfalls, several of those beaches often exceed USEPA Beach Action Values (BAVs). We investigated the role of microbial source tracking (MST) as a complement to routine beach monitoring at Chicago beaches. In summer 2016, water samples from nine Chicago beaches were analyzed for E. coli by culture and enterococci by qPCR. A total of 195 archived samples were then tested for human (HF183/BacR287, HumM2), canine (DG3, DG37), and avian (GFD) microbial source tracking (MST) markers. Associations between MST and general fecal indicator bacteria (FIB) measures were evaluated and stratified based on wet and dry weather definitions. Among the 195 samples, HF183/BacR287 was quantifiable in 4%, HumM2 in 1%, DG3 in 6%, DG37 in 2%, and GFD in 23%. The one beach with a dog area was far more likely to have DG3 present in the quantifiable range than other beaches. Exceedance of general FIB BAVs increased the odds of human, dog and avian marker detection. MST marker weighted-average fecal scores for DG3 was 2.4 times, DG37 was 2.1 times, and GFD was 1.6 times higher during wet compared to dry weather conditions. HF183/BacR287 weighted-average fecal scores were not associated with precipitation. Associations between FIB BAV exceedance and MST marker detection were generally stronger in wet weather. Incorporating MST testing into routine beach water monitoring can provide information that beach managers can use when developing protection plans for beaches not impacted by point sources.

Slow adoption of rapid testing: Beach monitoring and notification using qPCR.

In 2012 the US Environmental Protection Agency published new Recreational Water Quality Criteria, which for the first time, included criteria values and beach action values for quantitative polymerase chain reaction (qPCR) measurements or estimates of enterococci. The qPCR method makes it possible to generate indicator bacterial test results within several hours, and notify the public immediately, rather than the following day, which would be the case if culture methods were used. The BEach ACtion and Closing Online Notification (BEACON) data demonstrates that less than 1% of microbial beach water results for the years 2014-2018 were generated using qPCR. In order to assist jurisdictions considering the implementation of same-day beach water monitoring and notification, we describe a qPCR-based beach monitoring program in which a central laboratory tests water samples from up to 20 beaches per day, seven days per week, and reports the results to the public by noon. The transition from a culture-based monitoring program to a qPCR program, staffing, management, communications needs, fixed costs, and variable costs of the program are described. USEPA funding to support state and local governments implementing qPCR programs may be needed if the benefits of same-day notification regarding elevated health risks are to be realized.

Solar Powered Microplasma-Generated Ozone: Assessment of a Novel Point-of-Use Drinking Water Treatment Method.

Ozonation is widely used in high-income countries for water disinfection in centralized treatment facilities. New microplasma technology has reduced the energy requirements for ozone generation dramatically, such that a 15-watt solar panel is sufficient to produce small quantities of ozone. This technology has not been used previously for point-of-use drinking water treatment. We conducted a series of assessments of this technology, both in the laboratory and in homes of residents of a village in western Kenya, to estimate system efficacy and to determine if the solar-powered point-of-use water ozonation system appears safe and acceptable to end-users. In the laboratory, two hours of point-of-use ozonation reduced E. coli in 120 L of wastewater by a mean (standard deviation) of 2.3 (0.84) log-orders of magnitude and F+ coliphage by 1.54 (0.72). Based on laboratory efficacy, 10 families in Western Kenya used the system to treat 20 L of household stored water for two hours on a daily basis for eight weeks. Household stored water E. coli concentrations of >1000 most probable number (MPN)/100 mL were reduced by 1.56 (0.96) log removal value (LRV). No participants experienced symptoms of respiratory or mucous membrane irritation. Focus group research indicated that families who used the system for eight weeks had very favorable perceptions of the system, in part because it allowed them to charge mobile phones. Drinking water ozonation using microplasma technology may be a sustainable point-of-use treatment method, although system optimization and evaluations in other settings would be needed.

A Pilot Study of Chicago Waterways as Reservoirs of Multidrug-Resistant Enterobacteriaceae (MDR-Ent) in a High-Risk Region for Community-Acquired MDR-Ent Infection in Children.

Community-acquired multidrug resistant Enterobacteriaceae (MDR-Ent) infections continue to increase in the United States. In prior studies, we identified neighboring regions in Chicago, Illinois, where children have 5 to 6 times greater odds of MDR-Ent infections. To prevent community spread of MDR-Ent, we need to identify the MDR-Ent reservoirs. A pilot study of 4 Chicago waterways for MDR-Ent and associated antibiotic resistance genes (ARGs) was conducted. Three waterways (A1 to A3) are labeled safe for "incidental contact recreation" (e.g., kayaking), and A4 is a nonrecreational waterway that carries nondisinfected water. Surface water samples were collected and processed for standard bacterial culture and shotgun metagenomic sequencing. Generally, A3 and A4 (neighboring waterways which are not hydraulically connected) were strikingly similar in bacterial taxa, ARG profiles, and abundances of corresponding clades and genera within the Enterobacteriaceae Additionally, total ARG abundances recovered from the full microbial community were strongly correlated between A3 and A4 (R2 = 0.97). Escherichia coli numbers (per 100 ml water) were highest in A4 (783 most probable number [MPN]) and A3 (200 MPN) relative to A2 (84 MPN) and A1 (32 MPN). We found concerning ARGs in Enterobacteriaceae such as MCR-1 (colistin), Qnr and OqxA/B (quinolones), CTX-M, OXA and ACT/MIR (beta-lactams), and AAC (aminoglycosides). We found significant correlations in microbial community composition between nearby waterways that are not hydraulically connected, suggesting cross-seeding and the potential for mobility of ARGs. Enterobacteriaceae and ARG profiles support the hypothesized concerns that recreational waterways are a potential source of community-acquired MDR-Ent.

Multiple Sources of the Outbreak of Legionnaires' Disease in Genesee County, Michigan, in 2014 and 2015.

BACKGROUND: A community-wide outbreak of Legionnaires' disease (LD) occurred in Genesee County, Michigan, in 2014 and 2015. Previous reports about the outbreak are conflicting and have associated the outbreak with a change of water source in the city of Flint and, alternatively, to a Flint hospital. OBJECTIVE: The objective of this investigation was to independently identify relevant sources of Legionella pneumophila that likely resulted in the outbreak. METHODS: An independent, retrospective investigation of the outbreak was conducted, making use of public health, health care, and environmental data and whole-genome multilocus sequence typing (wgMLST) of clinical and environmental isolates. RESULTS: Strong evidence was found for a hospital-associated outbreak in both 2014 and 2015: a) 49% of cases had prior exposure to Flint hospital A, significantly higher than expected from Medicare admissions; b) hospital plumbing contained high levels of L. pneumophila; c) Legionella control measures in hospital plumbing aligned with subsidence of hospital A-associated cases; and d) wgMLST showed Legionella isolates from cases exposed to hospital A and from hospital plumbing to be highly similar. Multivariate analysis showed an increased risk of LD in 2014 for people residing in a home that received Flint water or was located in proximity to several Flint cooling towers. DISCUSSION: This is the first LD outbreak in the United States with evidence for three sources (in 2014): a) exposure to hospital A, b) receiving Flint water at home, and c) residential proximity to cooling towers; however, for 2015, evidence points to hospital A only. Each source could be associated with only a proportion of cases. A focus on a single source may have delayed recognition and remediation of other significant sources of L. pneumophila. https://doi.org/10.1289/EHP5663.

Evaluation of rapid qPCR method for quantification of E. coli at non-point source impacted Lake Michigan beaches.

Most Great Lakes communities rely on culture-based E. coli methods for monitoring fecal indicator bacteria (FIB) at recreational beaches. These cultivation methods require 18 or more hours to generate results. As a consequence, public notifications about beach action value (BAV) exceedance are based on prior-day water quality. Rapid qPCR monitoring of bacteria in beach water solves the 24-h delay problem, though the USEPA-approved qPCR method targets enterococci bacteria, while Great Lakes communities are familiar with E. coli monitoring. For an E. coli qPCR method to be useful for water quality management, it is important to systematically characterize method performance, and establish BAVs for public notification purposes. In this study, we 1) evaluated a draft USEPA E. coli qPCR method, 2) compared E. coli qPCR measurements with two established FIB (E. coli culture and enterococci qPCR) results, and explored potential strategies to establish E. coli qPCR BAV criteria in the absence of an epidemiological study. Based on analyses of 288 water samples collected from eight of Chicago's Lake Michigan beaches, the E. coli qPCR method demonstrates acceptable performance characteristics. The method is prone to low level DNA contamination, possibly originating from assay reagents derived from E. coli bacteria. Both E. coli and enterococci BAVs were exceeded in approximately 18% of the samples. E. coli qPCR values were correlated with both E. coli culture (r = 0.83; p < 0.0001) and enterococci qPCR (r = 0.67; p < 0.0001) values. The approach recommended by the USEPA in its Technical Support Material (TSM) was used to generate candidate E. coli qPCR BAVs, as was receiver operating characteristic (ROC) analysis. Potential BAV thresholds differed substantially, ranging from 200.9 calibrator cell equivalents (CCE)/100 mL (ROC analysis, enterococci qPCR BAV as the reference) to 1000 CCE/100 mL (TSM analysis, enterococci qPCR BAV as the reference). Because we found that different approaches to establishing potential BAVs generate quite different values, guidance from USEPA about approaches to defining comparable BAVs would be useful.

Evaluation of multiple laboratory performance and variability in analysis of recreational freshwaters by a rapid Escherichia coli qPCR method (Draft Method C).

There is interest in the application of rapid quantitative polymerase chain reaction (qPCR) methods for recreational freshwater quality monitoring of the fecal indicator bacteria Escherichia coli (E. coli). In this study we determined the performance of 21 laboratories in meeting proposed, standardized data quality acceptance (QA) criteria and the variability of target gene copy estimates from these laboratories in analyses of 18 shared surface water samples by a draft qPCR method developed by the U.S. Environmental Protection Agency (EPA) for E. coli. The participating laboratories ranged from academic and government laboratories with more extensive qPCR experience to "new" water quality and public health laboratories with relatively little previous experience in most cases. Failures to meet QA criteria for the method were observed in 24% of the total 376 test sample analyses. Of these failures, 39% came from two of the "new" laboratories. Likely factors contributing to QA failures included deviations in recommended procedures for the storage and preparation of reference and control materials. A master standard curve calibration model was also found to give lower overall variability in log10 target gene copy estimates than the delta-delta Ct (ΔΔCt) calibration model used in previous EPA qPCR methods. However, differences between the mean estimates from the two models were not significant and variability between laboratories was the greatest contributor to overall method variability in either case. Study findings demonstrate the technical feasibility of multiple laboratories implementing this or other qPCR water quality monitoring methods with similar data quality acceptance criteria but suggest that additional practice and/or assistance may be valuable, even for some more generally experienced qPCR laboratories. Special attention should be placed on providing and following explicit guidance on the preparation, storage and handling of reference and control materials.

Standardized data quality acceptance criteria for a rapid Escherichia coli qPCR method (Draft Method C) for water quality monitoring at recreational beaches.

There is growing interest in the application of rapid quantitative polymerase chain reaction (qPCR) and other PCR-based methods for recreational water quality monitoring and management programs. This interest has strengthened given the publication of U.S. Environmental Protection Agency (EPA)-validated qPCR methods for enterococci fecal indicator bacteria (FIB) and has extended to similar methods for Escherichia coli (E. coli) FIB. Implementation of qPCR-based methods in monitoring programs can be facilitated by confidence in the quality of the data produced by these methods. Data quality can be determined through the establishment of a series of specifications that should reflect good laboratory practice. Ideally, these specifications will also account for the typical variability of data coming from multiple users of the method. This study developed proposed standardized data quality acceptance criteria that were established for important calibration model parameters and/or controls from a new qPCR method for E. coli (EPA Draft Method C) based upon data that was generated by 21 laboratories. Each laboratory followed a standardized protocol utilizing the same prescribed reagents and reference and control materials. After removal of outliers, statistical modeling based on a hierarchical Bayesian method was used to establish metrics for assay standard curve slope, intercept and lower limit of quantification that included between-laboratory, replicate testing within laboratory, and random error variability. A nested analysis of variance (ANOVA) was used to establish metrics for calibrator/positive control, negative control, and replicate sample analysis data. These data acceptance criteria should help those who may evaluate the technical quality of future findings from the method, as well as those who might use the method in the future. Furthermore, these benchmarks and the approaches described for determining them may be helpful to method users seeking to establish comparable laboratory-specific criteria if changes in the reference and/or control materials must be made.

Minigrants to Local Health Departments: An Opportunity to Promote Climate Change Preparedness.

CONTEXT: Human health is threatened by climate change. While the public health workforce is concerned about climate change, local health department (LHD) administrators have reported insufficient knowledge and resources to address climate change. Minigrants from state to LHDs have been used to promote a variety of local public health initiatives. OBJECTIVE: To describe the minigrant approach used by state health departments implementing the Centers for Disease Control and Prevention's (CDC's) Building Resilience Against Climate Effects (BRACE) framework, to highlight successes of this approach in promoting climate change preparedness at LHDs, and to describe challenges encountered. DESIGN: Cross-sectional survey and discussion. INTERVENTION: State-level recipients of CDC funding issued minigrants to local public health entities to promote climate change preparedness, adaptation, and resilience. MAIN OUTCOME MEASURES: The amount of funding, number of LHDs funded per state, goals, selection process, evaluation process, outcomes, successes, and challenges of the minigrant programs. RESULTS: Six state-level recipients of CDC funding for BRACE framework implementation awarded minigrants ranging from $7700 to $28 500 per year to 44 unique local jurisdictions. Common goals of the minigrants included capacity building, forging partnerships with entities outside of health departments, incorporating climate change information into existing programs, and developing adaptation plans. Recipients of minigrants reported increases in knowledge, engagement with diverse stakeholders, and the incorporation of climate change content into existing programs. Challenges included addressing climate change in regions where the topic is politically sensitive, as well as the uncertainty about the long-term sustainability of local projects beyond the term of minigrant support. CONCLUSIONS: Minigrants can increase local public health capacity to address climate change. Jurisdictions that wish to utilize minigrant mechanisms to promote climate change adaptation and preparedness at the local level may benefit from the experience of the 6 states and 44 local health programs described.

Estimate of incidence and cost of recreational waterborne illness on United States surface waters.

BACKGROUND: Activities such as swimming, paddling, motor-boating, and fishing are relatively common on US surface waters. Water recreators have a higher rate of acute gastrointestinal illness, along with other illnesses including respiratory, ear, eye, and skin symptoms, compared to non-water recreators. The quantity and costs of such illnesses are unknown on a national scale. METHODS: Recreational waterborne illness incidence and severity were estimated using data from prospective cohort studies of water recreation, reports of recreational waterborne disease outbreaks, and national water recreation statistics. Costs associated with medication use, healthcare provider visits, emergency department (ED) visits, hospitalizations, lost productivity, long-term sequelae, and mortality were aggregated. RESULTS: An estimated 4 billion surface water recreation events occur annually, resulting in an estimated 90 million illnesses nationwide and costs of $2.2- $3.7 billion annually (central 90% of values). Illnesses of moderate severity (visit to a health care provider or ED) were responsible for over 65% of the economic burden (central 90% of values: $1.4- $2.4 billion); severe illnesses (result in hospitalization or death) were responsible for approximately 8% of the total economic burden (central 90% of values: $108- $614 million). CONCLUSION: Recreational waterborne illnesses are associated with a substantial economic burden. These findings may be useful in cost-benefit analysis for water quality improvement and other risk reduction initiatives.

Monitoring urban beaches with qPCR vs. culture measures of fecal indicator bacteria: Implications for public notification.

BACKGROUND: The United States Environmental Protection Agency has established methods for testing beach water using the rapid quantitative polymerase chain reaction (qPCR) method, as well as "beach action values" so that the results of such testing can be used to make same-day beach management decisions. Despite its numerous advantages over culture-based monitoring approaches, qPCR monitoring has yet to become widely used in the US or elsewhere. Considering qPCR results obtained on a given day as the best available measure of that day's water quality, we evaluated the frequency of correct vs. incorrect beach management decisions that are driven by culture testing. METHODS: Beaches in Chicago, USA, were monitored using E. coli culture and enterococci qPCR methods over 894 beach-days in the summers of 2015 and 2016. Agreement in beach management using the two methods, after taking into account agreement due to chance, was summarized using Cohen's kappa statistic. RESULTS: No meaningful agreement (beyond that expected by chance) was observed between beach management actions driven by the two pieces of information available to beach managers on a given day: enterococci qPCR results ofsamples collected that morning and E. coli culture results of samples collected the previous day. The E. coli culture beach action value was exceeded 3.4 times more frequently than the enterococci qPCR beach action value (22.6 vs. 6.6% of beach-days). CONCLUSIONS: The largest evaluation of qPCR-based beach monitoring to date provides little scientific rationale for continued E. coli culture testing of beach water in our setting. The observation that the E. coli culture beach action value was exceeded three times as frequently as the enterococci qPCR beach action value suggests that, although the beach action values for bacteria using different measurement methods are thought to provide comparable information about health risk, this does not appear to be the case in all settings.