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Wastewater surveillance has emerged as a valuable tool for monitoring infectious disease agents including SARS-CoV-2 and Mpox virus. However, detecting the Mpox virus in wastewater is particularly challenging due to its relatively low prevalence in the community. In this study, we detected Mpox virus in wastewater from a US-Mexico border city with a low prevalence of Mpox disease during February and March 2023 using real-time PCR assays targeting the C22L, F3L, and F8L genes. An increasing trend of viral concentration was observed 1~2 weeks earlier than when the Mpox case was reported. Further sequencing and epidemiological analysis provided supporting evidence for unreported Mpox infections in the city. This study showcases a combined approach with multiple molecular assays for efficient detection of the Mpox virus in wastewater in a low-prevalence area. The findings emphasize the value of wastewater surveillance as a timely identification tool for infectious diseases in low-prevalence areas, and the need for heightened vigilance to control the spread of infectious diseases in such settings.

Wastewater is a discarded human by-product but analyzing it may help us understand the health of communities. Epidemiologists first analyzed wastewater to track outbreaks of poliovirus decades ago, but so-called wastewater-based epidemiology was reinvigorated to monitor SARS-CoV-2 levels. Current approaches overlook the activity of most human viruses and preclude a deeper understanding of human virome community dynamics. We conducted a comprehensive sequencing-based analysis of 363 longitudinal wastewater samples from ten distinct sites in two major cities. Over 450 distinct pathogenic viruses were detected. Sequencing reads of established pathogens and emerging viruses correlated to clinical data sets. Viral communities were tightly organized by space and time. Finally, the most abundant human viruses yielded sequence variant information consistent with regional spread and evolution. We reveal the viral landscape of human wastewater and its potential to improve our understanding of outbreaks, transmission, and its effects on overall population health.One-Sentence SummaryWastewater contains a trickle of circulating human viruses, and now we can sequence them to better track community transmission.

The border city of El Paso, Texas, and its water utility, El Paso Water, initiated a SARS-CoV-2 wastewater monitoring program to assess virus trends and the appropriateness of a wastewater monitoring program for the community. Nearly weekly sample collection at four wastewater treatment facilities (WWTFs), serving distinct regions of the city, was analyzed for SARS-CoV-2 genes using the CDC 2019-Novel coronavirus Real-Time RT-PCR diagnostic panel. Virus concentrations ranged from 86.7 to 268,000 gc/L, varying across time and at each WWTF. The lag time between virus concentrations in wastewater and reported COVID-19 case rates (per 100,00 population) ranged from 4-24 days for the four WWTFs, with the strongest trend occurring from November 2021 - June 2022. This study is an assessment of the utility of a geographically refined SARS-CoV-2 wastewater monitoring program to supplement public health efforts that will manage the virus as it becomes endemic in El Paso.

Rapid and accurate diagnosis of infections is fundamental to containment of disease. Several monkeypox virus (MPV) real-time diagnostic assays have been recommended by the CDC; however, the specificity of the primers and probes in these assays for the ongoing MPV outbreak has not been investigated. We analyzed the primer and probe sequences present in the CDC recommended monkeypox virus (MPV) generic real-time PCR assay by aligning those sequences against 1,730 MPV complete genomes reported in 2022 worldwide. Sequence mismatches were found in 99.08% and 97.46% of genomes for the MPV generic forward and reverse primers, respectively. Mismatch-corrected primers were synthetized and compared to the generic assay for MPV detection. Results showed that the two primer-template mismatches resulted in a ∼11-fold underestimation of initial template DNA in the reaction and 4-fold increase in the 95% LOD. We further evaluated the specificity of seven other real-time PCR assays used for MPV and orthopoxvirus (OPV) detection and identified two assays with the highest matching score (>99.6%) to the global MPV genome database in 2022. Genetic variations in the primer-probe regions across MPV genomes could indicate the temporal and spatial emergence pattern of monkeypox disease. Our results show that the current MPV real-time generic assay may not be optimal to accurately detect MPV, and the mismatch-corrected assay with full complementarity between primers and current MPV genomes could provide a more sensitive and accurate detection of MPV.

Aims Contaminated laundry can spread infections. However, current directives for safe laundering are limited to healthcare settings and not reflective of domestic conditions. We aimed to use quantitative microbial risk assessment to evaluate household laundering practices (e.g., detergent selection, washing and drying temperatures, and sanitizer use) relative to log10 reductions in pathogens and infection risks during the clothes sorting, washer/dryer loading, folding and storing steps. Methods and results Using published data, we characterized laundry infection risks for respiratory and enteric pathogens relative to a single user contact scenario and a 1.0 × 10-6 acceptable risk threshold. For respiratory pathogens, risks following cold water wash temperatures (e.g. median 14.4℃) and standard detergents ranged from 2.2 × 10-5 to 2.2 × 10-7 . Use of advanced, enzymatic detergents reduced risks to 8.6 × 10-8 and 2.2 × 10-11 respectively. For enteric pathogens, however, hot water, advanced detergents, sanitizing agents and drying are needed to reach risk targets. Significance and impact of the study Conclusions provide guidance for household laundry practices to achieve targeted risk reductions, given a single user contact scenario. A key finding was that hand hygiene implemented at critical control points in the laundering process was the most significant driver of infection prevention, additionally reducing infection risks by up to 6 log10 .

Wastewater-based surveillance (WBS) has been widely used as a public health tool to monitor SARS-CoV-2 transmission. However, epidemiological inference from WBS data remains understudied and limits its application. In this study, we have established a quantitative framework to estimate COVID-19 prevalence and predict SARS-CoV-2 transmission through integrating WBS data into an SEIR-V model. We conceptually divide the individual-level viral shedding course into exposed, infectious, and recovery phases as an analogy to the compartments in population-level SEIR model. We demonstrated that the temperature effect on viral losses in the sewer can be straightforwardly incorporated in our framework. Using WBS data from the second wave of the pandemic (Oct 02, 2020 – Jan 25, 2021) in the Great Boston area, we showed that the SEIR-V model successfully recapitulates the temporal dynamics of viral load in wastewater and predicts the true number of cases peaked earlier and higher than the number of reported cases by 16 days and 8.6 folds (R = 0.93), respectively. This work showcases a simple, yet effective method to bridge WBS and quantitative epidemiological modeling to estimate the prevalence and transmission of SARS-CoV-2 in the sewershed, which could facilitate the application of wastewater surveillance of infectious diseases for epidemiological inference and inform public health actions.

Marine oil spills and the resulting environmental contamination is common along coastal areas; however, information is lacking about the safety of impacted beaches for public use, especially for the most vulnerable population: children. One route of exposure for children at oil impacted beaches is through contact with sands. The purpose of this study was to evaluate beach sand skin adherence for children under the age of seven. Each of 122 children participated in a hand press trial conducted at one of four different U.S. beaches (two in Miami, FL, and two in Galveston, TX USA). During the hand press trials, hand conditions of the children were randomized (dry, wet, or with sunscreen), and soil adherence (mass of sand per palmar surface area of the hand) and the maximum pressure applied (force applied per area of hand) was measured and calculated. Each child was instructed to press their hands on a soil laden tray for 5 s and pressure of contact was measured using a scale. Results (n = 98) showed that the average soil adherence for both palmar hands across the four beaches ranged from 0.200 to 234 mg/cm2 with an average of 35.7 mg/cm2, with boys (40.4 mg/cm2) showing slightly higher means than girls (31.7 mg/cm2), but these differences were not significant even after adjusting for age. Among the three conditions evaluated, the highest loading was measured for children with wet hands (mean 65.3 mg/cm2), followed by dry hands (mean 24.5 mg/cm2). Sunscreen hands (mean 23.2 mg/cm2) had the lowest loadings. The pressure of contact ranged from 0.180 to 1.69 psi and varied by age groups and by height and weight, where pressure of contact did not have a significant influence on soil adherence. The average adhered sand grain size and average ambient sand grain size both had a statistically significant impact on hand soil adherence. Overall results from this study can be utilized in exposure and risk assessment models to evaluate the possible health impacts from contaminants found in beach sands.

Various methods exist to determine the surface area of hands. The consistency of these methods is essential given that risk assessments utilize hand surface area (HSA) to quantify exposure to environmental contaminants. HSA is also utilized in the clinical setting to estimate size of burns, and to determine specific treatments and medication dosages. A reliable method of surface area measurement is important to guide these decisions, especially in children who are vulnerable to environmental contaminants and medication side effects. Despite this, fewer HSA-determining studies have been performed for children compared to adults. In this study, 122 children completed hand tracings, and the tracings were digitized using an ImageJ program to determine HSA. Six previously published methods of determining HSA were utilized based on the child’s height, weight, and length and width of hand. Children were analyzed by age group including 0–2, 3–4, and 5–6 years. The HSA measurements determined by five of the six methods were statistically different from HSA determined using direct hand tracings/Image J methodology (p

During time-periods oil slicks are in the marine environment (age-at-sea), weathering causes significant changes in composition and mass loss (depletion) of oil spill chemicals including the more toxic polycyclic aromatic hydrocarbons (PAHs). The goal of this study was to estimate the age-at-sea of weathered oil slicks using the oil spill module of the Connectivity Modeling System and to use this age to interpret PAH concentration measurements. Percent depletion (PD) for each measurement was computed as the percentage difference between the original and measured PAH concentration in the crude oil and weathered oil slicks, normalized upon the mass losses relative to hopane. Mean PD increased with estimated age-at-sea for all PAHs. Less PD was observed for alkylated than for parent PAHs, likely due to decreasing vapor pressure with increasing degree of alkylation. We conclude that estimated age-at-sea can be used to explain PAH depletion in weathered oil slicks. We propose PAH vapor pressure can be coupled with the model to expand capacity for predicting concentration distributions of individual parent and alkylated PAHs in weathered oil along the coastline. This new module will advance the science supporting oil spill response by providing more certain estimates of health risks from oil spills.

The 2010 DWH disaster generated atmospheric pollutants of health concern which reached the Gulf Coast. This study evaluated whether changes in coastal air quality due to the disaster were captured by aerosol optical depth (AOD) estimated using satellite data and by ground-based monitoring of air pollution, including fine particulate matter ≤2.5 μm in aerodynamic diameter (PM

Anthropogenic contamination of beaches in the south of Brazil was assessed by detection of Escherichia coli, human mastadenovirus species C (HAdV-C) and F (HAdV-F) and hepatitis E virus (HEV). Sampling was carried out in October (2016), and in January, April and July (2017). Water, sediment, sea surface microlayer (SML), bivalves, and air sentinel samples were evaluated. Quantitative microbiological risk assessment (QMRA) was used to estimate the probability of swimmer infection. HAdV-C was present in 26% of the samples, for both qPCR and viral isolation. The highest rates of detection in genomic copies (GC) were in water (2.42E+10 GC/L), SML (2.08E+10 GC/L), sediment (3.82E+08 GC/g) and bivalves (3.91E+07 GC/g). QMRA estimated daily and annual risks with a maximum value (9.99E-01) in almost all of the samples. Viable HAdV-C was often detected in the SML, pointing that this is a source of infection for people bathing in these waters.

Jumping on the bed is a favorite behavior of children; however, no study has investigated the increased air pollutants resulting from jumping on the bed. Therefore, we aimed to investigate the elevated concentrations of particulate matter (PM) and bioaerosols from jumping on the bed and making the bed. Simulation of jumping on the bed and making the bed was performed at sixty schoolchildren's houses in Taiwan. PM10, PM2.5, PM1 (PM with aerodynamic diameter less than 10, 2.5, and 1 μm, respectively) and airborne bacteria, fungi and endotoxin concentrations were simultaneously measured over simulation and background periods. Our results show the increase of PM10, PM2.5, PM1, airborne bacteria and fungi through the behavior of jumping on the bed (by 414 μg m-3, 353 μg m-3, 349 μg m-3, 6569 CFU m-3 and 978 CFU m-3, respectively). When making the bed, the PM10, PM2.5, PM1, airborne bacteria and fungi also significantly increased by 4.69 μg m-3, 4.09 μg m-3, 4.15 μg m-3, 8569 CFU m-3, and 779 CFU m-3, respectively. Airborne endotoxin concentrations significantly increased by 21.76 EU m-3 following jumping on the bed and making the bed. Moreover, when jumping on the bed, higher PM2.5 and PM1 concentrations in houses with furry pets rather than no furry pets, and less airborne fungi in apartments than in townhouses were found. For making the bed, lower airborne fungi was found in houses using essential oils rather than no essential oils using. The airborne endotoxin concentrations were positively associated with furry pets and smokers in the homes and negatively correlated to the home with window opening with a statistical significance during the periods of jumping on the bed and making the bed. In conclusion, significant increases of PM and bioaerosols during jumping on the bed and making the bed may need to be concerned.

In a study to evaluate beach play activities, 120 children were videotaped to observe and quantify factors that could influence their exposure to contaminants in the beach environment. Children aged 1 to 6 years were followed by researchers with video cameras at beaches (two in Miami, Florida and two in Galveston, Texas) for approximately one hour each. Factors evaluated included time spent in various beach locations, various activities engaged in, and various surfaces contacted (including contacts by hand and mouth). Activities recorded in the videos were transcribed to text files to allow for quantitative analyses. Across all sexes, age groups, and beaches, Wading was the most common activity and Seawater was the most common location where children played. The left hand was found to not be in contact with objects most of the time, while the right hand, considered the most dominant hand in most cases, contacted Plastic-Toys the most. Although activity patterns collection through videotaping and videotranslation can be labor-intensive, once collected, they can be widely useful for estimates of exposures to all contaminants in the beach environment (e.g., microorganisms and chemicals) as well as UV exposure, with considerations for whether the contaminants are found in water, sand or both. These activity patterns were collected to potentially look at exposures following the Deepwater Horizon 2010 Spill.

The human health impact from exposure to contaminated shorelines following an oil spill event has been investigated to some extent. However, the health risks to children have largely been characterized through the use of surveys and extrapolation from adult health outcomes. There is limited information on children&rsquo, s behaviors during beach play requiring assumptions made based on observations from play activities in home settings. The Beach Exposure and Child Health Study (BEACHES) quantified specific beach activities that can be used to inform human health risk assessments of children playing on beaches impacted by oil spills. The results of this study characterize children&rsquo, s risk of cancer from exposure to oil spill chemicals by incorporating exposure-related information collected from the BEACHES study and by assuming oral, dermal, and inhalation exposure routes. Point risk estimates are compared with a previous, similar study that applied default exposure parameter values obtained from the published literature. The point risk estimates informed by BEACHES data are one order of magnitude lower compared with the previous risk assessment, with dermal exposures the overall risk driver in both. Additional Monte Carlo simulations evaluating the BEACHES data provide ranges of health risks with the highest estimates associated with dermal and oral exposure routes.

The Beach Exposure and Child Health Study (BEACHES) quantified the behavior of children at recreational beach areas to evaluate how various behaviors might affect their exposure to environmental contaminants such as bacteria and chemicals. Due to limited information in the study about abrasions, we conducted a literature review to examine how marine bacteria cause infections in open wounds. The literature review revealed possible adverse health effects from the bacterium Vibrio vulnificus due to its increasing prevalence and the severity of infection. We used data from the BEACHES study to review children&rsquo, s behavior and their susceptibility to abrasions. Children six years of age and younger were evaluated before and after 1 hour of play for open or healing abrasions at two beaches in Miami-Dade County, Florida (Crandon and Haulover), and two beaches in Galveston County, Texas (Stewart and Seawall). The children were videotaped to monitor their activities and to determine the behavior that would increase their susceptibility to obtaining abrasions. Overall, 58.2% of the children had at least one existing abrasion before playing at the beach, while 8.2% of the children acquired a new abrasion during their time at the beach. Children who acquired new abrasions most often played in the sea water, with new abrasions most frequently occurring on exposed skin surfaces such as the knees. Proper wound care before and after visiting the beach should be encouraged to minimize the risk of bacterial infection, especially considering the possible detrimental impacts that can be caused by some bacterial pathogens through wound exposures.

Skin adherence (SA) of soil affects exposure from soil contaminants through dermal routes via loading on the skin and through ingestion routes through hand to mouth activities. The objectives of this study were to evaluate the relationships between adherence versus child-specific and environmental factors. Two sets of soil-to-skin adherence were evaluated. The first was based on loading on hands following hand presses (Hand SA). The second was based on body rinses following one hour of play activities on the beach (Body SA). Results for 98&ndash, 119 children conducted at four beach sites show that mean Hand SA was 35.7 mg/cm2 (std. dev. 41.8 mg/cm2), while Body SA based on full coverage was 352.3 mg/cm2 (std. dev. 250.4 mg/cm2). Statistically significant differences in Body SA were observed between male (419.2 mg/cm2) and female (300.4 mg/cm2) children (p &lt, 0.05). No significant difference by sex was found for Hand SA. Other statistically different observations were that Hand SA (p &lt, 0.05), but not Body SA, differed across the four beaches (p &lt, 0.05). For Hand SA, this difference was associated soil size variability across the beaches. Hand and Body SA values measured during this study are recommended for use in risk assessments that evaluate beach exposures to oil spill chemicals for young children.

Faecal-oral transmission of SARS-CoV-2 is a hot topic and additional research is needed to elucidate the risks of the novel coronavirus in sanitation systems. This is the first article that investigates the potential health risks of SARS-CoV-2 in sewage to wastewater treatment plants (WWTPs) workers. A quantitative microbial risk assessment (QMRA) is applied for three COVID-19 scenarios (moderate, aggressive and extreme) to study the effect of different stages of the pandemic, in terms of percentage of infected population, on the probability of infection. Results reveal that estimates of viral loads in sewage at the entrance of WWTPs ranged from 1.03×102 to 1.31×104 GC.mL−1 (0.1 to 13.06 PFU.mL−1, respectively) and that estimated risks for the aggressive and extreme scenarios (6.5×10−3 and 3.1×10−2, respectively) were likely to be above a WHO benchmark of tolerable risk used for virus infection of 10−3 and higher than the risk of infection of E. coli, used herein as common pathogen indicator for a relative comparison, thus reinforcing the concern of sewage systems as a transmission pathway of SARS-CoV-2. These findings are helpful as an early-warning tool and in prioritizing upcoming risk management strategies in the sanitation sector during COVID-19 pandemic.

Marine oil spills and the resulting environmental contamination is common along coastal areas; however, information is lacking about the safety of impacted beaches for public use, especially for the most vulnerable population: children. One route of exposure for children at oil impacted beaches is through contact with sands. The purpose of this study was to evaluate beach sand skin adherence for children under the age of seven. Each of 122 children participated in a hand press trial conducted at one of four different U.S. beaches (two in Miami, FL, and two in Galveston, TX USA). During the hand press trials, hand conditions of the children were randomized (dry, wet, or with sunscreen), and soil adherence (mass of sand per palmar surface area of the hand) and the maximum pressure applied (force applied per area of hand) was measured and calculated. Each child was instructed to press their hands on a soil laden tray for 5 s and pressure of contact was measured using a scale. Results (n = 98) showed that the average soil adherence for both palmar hands across the four beaches ranged from 0.200 to 234 mg/cm

Gastrointestinal (GI) illness risks associated with exposure to waters impacted by human and nonhuman fecal sources were estimated using quantitative microbial risk assessment (QMRA). Microbial source tracking (MST) results had identified Escherichia coli (E. coli) contributors to the waterbody as human and unidentified (10%), cattle and domestic animals (25%), and wildlife (65%) in a rural watershed. The illness risks associated with ingestion during recreation were calculated by assigning reference pathogens for each contributing source and using pathogen dose&ndash, response relationships. The risk of GI illness was calculated for a specific sampling site with a geometric mean of E. coli of 163 colony forming units (cfu) 100 mL&minus, 1, and the recreational standard of E. coli, 126 cfu 100 mL&minus, 1. While the most frequent sources of fecal indicator bacteria at the sampling site were nonhuman, the risk of illness from norovirus, the reference pathogen representing human waste, contributed the greatest risk to human health. This study serves as a preliminary review regarding the potential for incorporating results from library-dependent MST to inform a QMRA for recreational waters. The simulations indicated that identifying the sources contributing to the bacterial impairment is critical to estimate the human health risk associated with recreation in a waterbody.

Strawberries are vulnerable to harboring microbial pathogens because they are generally not washed due to their perishable nature. The focus of this study was to quantify the reduction in infection risks associated with non-O157 Shiga toxin producing Escherichia coli serotypes contaminated strawberries if the strawberries are exposed to low doses ∼1 kGy (kiloGray) of electron beam (eBeam) irradiation. A cocktail of six serotypes of non O157 E. coli namely, O26:H11, O45:H2, O103:H2, O111:NM, O121:H19, and O145 was employed. Strawberry puree rather than whole strawberries were used in this study to ensure dose uniformity that is critical for accurate interpretation of microbial reduction. The results show that when these serotypes are exposed to ≤1 kGy eBeam dose, there is approximately 4-log reduction in their numbers when they are present within a strawberry matrix (puree). Quantitative microbial risk assessments suggest that if a typical strawberry serving (150 g) was heavily contaminated (∼105 CFU/serving size), 2 out of 10 susceptible individuals (20%) would get sick (without eBeam treatment). However, if these contaminated strawberries had been treated with 1 kGy of eBeam dose, the infection risks would have be significantly reduced to approximately 4 out of every 100,000 individuals (0.004%). Similarly, even at low levels of contamination (∼102 CFU/serving), the infection risks would be reduced from 6 out of 10,000 susceptible individuals to approximately 4 out of 100 million susceptible individuals.

High concentrations of air pollutants and increased morbidity and mortality rates are found in industrial areas, especially for the susceptible group, children, however, most studies use atmospheric dispersion modeling to estimate household air pollutants. Therefore, the aim of this study was to assess the indoor air quality, e.g., CO, CO2, NO2, SO2, O3, particulate matter with aerodynamic diameter less than 2.5 &mu, m (PM2.5), and their influence factors in children&rsquo, s homes in an industrial city. Children in the &ldquo, general school&rdquo, &ldquo, traffic school&rdquo, and &ldquo, industrial school&rdquo, were randomly and proportionally selected. Air pollutants were sampled for 24 h in the living rooms and on the balcony of their houses and questionnaires of time&ndash, microenvironment&ndash, activity-diary were recorded. The indoor CO concentration of the traffic area was significantly higher than that of the industrial area and the general area. In regard to the effects of window opening, household NO2 and PM2.5 concentrations during window opening periods were significantly higher than of the reference periods. For the influence of cooking, indoor CO2, NO2, and PM2.5 levels during the cooking periods were significantly higher than that of the reference periods. The indoor air quality of children in industrial cities were affected by residential areas and household activities.

Background: Oil spill chemicals (OSCs) result not only from the crude oil components but also from dispersants used in the clean-up activities, where some may result in adverse health effects under certain exposure and dosage conditions. One of the main populations of concern for exposure to OSCs are children, who are frequent beach users. Activities such as ingestion of and digging in sand can increase dermal and ingestion exposure. Longer times spent at the beach can also increase exposures for all routes. Objectives: The Beach Exposure and Child Health Study (BEaCHeS) was initiated to evaluate the risk of exposure to children from oil contaminants. Reported here are results for surveys collected, as a part of the project, to address exposure-related behavior patterns and risk perception for parents or guardians who visit the beach. Methods: Over 400 parental surveys were collected at four beaches, two in Miami and two in Texas, to evaluate children&rsquo, s exposure related activities. Surveys consisted of three general sections: demographics, exposure, and risk perception. Surveys were analyzed in REDcap and Stata to evaluate demographic and regional differences on activities related to beach behavior and potential exposures to oil contaminants (e.g., how much time spent on beach, cleaning habits following beach activities). The statistical analysis included the mean and standard errors, along with regressions to evaluate associations between parameters. Results: Overall, the data showed high variability in how children play on the beach, influenced more by age and less by gender. Variations were also seen in certain variables by beach region (e.g., hygiene practices). By race, variations were seen in income, distance of travel to beach, and preferred method of communication for beach warning. Other important findings are reflected in the article. Discussion: The data presented here may prove useful for those evaluating children exposures to a variety of contaminants, chemical, or bacterial in origin. In addition, coastal managers may find the risk perception and general behaviors useful for planning and maintenance of beach areas.

BACKGROUND To date, the effect of household airborne pollutants on the association between airborne endotoxin and lung function of schoolchildren is unknown. OBJECTIVES The objective of this study is to evaluate whether indoor air pollutants such as carbon monoxide (CO), carbon dioxide (CO2), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), particulate matter with aerodynamic diameter

Oil Spill Chemicals (OSCs) represent a risk to the environment and human health, especially in nearshore environments used for recreational purposes. Importantly, the starting point for human health risk assessment is to define the concentration of OSCs at nearshore locations. The objective of this study was to evaluate nearshore sampling data of OSC concentrations in different environmental matrices within time-space specific categories. The categories correspond to OSC concentration values for samples collected prior to nearshore oiling, post nearshore oiling and at no time impacted by oil as predicted by historic oil spill trajectories generated by an Oil Spill Trajectory Model. In general, concentration values for the post category were higher than prior which were higher than unimpacted. Results show differences in PAH concentration patterns within each matrix and for each category. Concentration frequency distributions for most chemicals in each category were log-normally distributed.

Oil spills can result in changes in chemical concentrations along coastlines. In prior work, these concentration changes were used to evaluate the date sediment was impacted by oil (i.e., oil exposure date). The objective of the current study was to build upon prior work by using the oil exposure date to compute oil spill chemical (OSC) concentrations in shoreline sediments before and after exposure. The new method was applied to OSC concentration measures collected during the Deepwater Horizon oil spill with an emphasis on evaluating before and after concentrations in muddy versus sandy regions. The procedure defined a grid that overlaid coastal areas with chemical concentration measurement locations. These grids were then aggregated into clusters to allow the assignment of chemical concentration measurements to a uniform coastal type. Performance of the method was illustrated for ten chemicals individually by cluster, and collectively for all chemicals and all clusters. Results show statistically significant differences between chemical concentrations before and after the calculated oil exposure dates (p

Background It is generally agreed that contaminated hospital surfaces play a role in the transmission of hospital-acquired infections (HAIs). The ability of an antimicrobial agent, engineered at Emory University, to reduce bacterial bioburden on hospital surfaces was examined. A quantitative microbial risk assessment was also conducted to quantify the potential reduction of human health risks associated with application of this antimicrobial product. Methods A 1-arm, prospective observational study was conducted. High-frequency contact surfaces within 18 hospital patient rooms were sampled in between patient use. Negative binomial regression with repeated measures was used to examine log CFU/100 cm 2 reductions in total, gram-negative, and Staphylococcus aureus microorganisms. Standard risk assessment methods were used. Results Multivariate regression demonstrated significant reductions in gram-negative ( P S aureus ( P = .009) bacteria with increasing patient turnover. No reduction was observed in total bacteria ( P = .93). Infection risks were reduced by 4 and 3 logs for gram-positive and gram-negative bacteria, respectively. These risk reductions, along with HAI survey studies, suggest that application of this antimicrobial product could prevent as many as 5%-10% of HAIs. Conclusions This study was the first evaluation of a distinctive antimicrobial agent for hospital surface treatment. The findings provide support for the utility of an antimicrobial product in potentially reducing HAI transmission from contaminated environment surfaces.

Faecal-oral transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is yet to be validated, but it is a critical issue and additional research is needed to elucidate the risks of the novel coronavirus in sanitation systems. This is the first study that investigates the potential health risks of SARS-CoV-2 in sewage to wastewater treatment plant (WWTP) workers. A quantitative microbial risk assessment (QMRA) is applied for three COVID-19 scenarios (moderate, aggressive and extreme) to study the effects of different stages of the pandemic in terms of percentage of infected population on the probability of infection to WWTP workers. A dose-response model for SARS-CoV-1 (as a surrogate pathogen) is assumed in the QMRA for SARS-CoV-2 using an exponential model with k = 4.1 × 102. Literature data are incorporated to inform assumptions for calculating the viral load, develop the model, and derive a tolerable infection risk. Results reveal that estimates of viral RNA in sewage at the entrance of WWTPs ranged from 4.14 × 101 to 5.23 × 103 GC·mL−1 (viable virus concentration from 0.04 to 5.23 PFU·mL−1, respectively). In addition, estimated risks for the aggressive and extreme scenarios (2.6 × 10−3 and 1.3 × 10−2, respectively) were likely to be above the derived tolerable infection risk for SARS-CoV-2 of 5.5 × 10−4 pppy, thus reinforcing the concern of sewage systems as a possible transmission pathway of SARS-CoV-2. These findings are helpful as an early health warning tool and in prioritizing upcoming risk management strategies, such as Emergency Response Plans (ERPs) for water and sanitation operators during the COVID-19 and future pandemics., Graphical abstract Unlabelled Image, Highlights • Viral loads and infectivity of SARS-CoV-2 in sewage affluent to WWTPs were estimated. • QMRA estimated the risk of infection for WWTP workers in three COVID-19 scenarios. • QMRA risk estimates will provide critical input for risk management decisions. • Wastewater operators can benefit from QMRA-informed Emergency Response Plans.

Oil spills can result in changes in chemical contaminant concentrations along coastlines. When concentrations are measured along the Gulf of Mexico over time, this information can be used to evaluate oil spill shoreline exposure dates. The objective of this research was to identify more accurate oil exposure dates based on oil spill chemical concentrations changes (CCC) within sediments in coastal zones after oil spills. The results could be used to help improve oil transport models and to improve estimates of oil landings within the nearshore. The CCC method was based on separating the target coastal zone into segments and then documenting the timing of large increases in concentration for specific oil spill chemicals (OSCs) within each segment. The dataset from the Deepwater Horizon (DWH) oil spill was used to illustrate the application of the method. Some differences in exposure dates were observed between the CCC method and between oil spill trajectories. Differences may have been caused by mixing at the freshwater and sea water interface, nearshore circulation features, and the possible influence of submerged oil that is unaccounted for by oil spill trajectories. Overall, this research highlights the benefit of using an integrated approach to confirm the timing of shoreline exposure.

Limited models are available to estimate human physical health risks (e.g., probability of outcomes such as lung disease, cancer, skin disease) from exposure to chemicals resulting from oil spills that may occur offshore and later impact coastline spills. An approach is presented to assess physical health risks from oil spills that involves establishing a platform capable of assessing aggregate health risk (via inhalation, ingestion, and dermal exposure routes). Gaps include the need to develop models reflecting oil spill concentration distributions given the influence from environmental, physical, biological and chemical factors. Human activities need to be quantified for different populations including emergency response workers, fishermen, shellfish consumers, and children who play at beaches that may be impacted by oil spills. Work is also needed in developing comprehensive toxicological profiles for the majority of chemicals - including dispersants found in oil spills - and to estimate toxicity from mixtures.

In this study, total coliforms (TC), Escherichia coli, enterovirus (EV), rotavirus (RV), and human mastadenovirus species C and F (HAdV-C and HAdV-F) were evaluated in water samples from Belo Stream. For HAdV-C and F, the infectivity was assessed by integrated cell culture quantitative real-time polymerase chain reaction (ICC-qPCR). Samples were collected monthly (May/2015 to April/2016) at four sites. Viral analyses were performed for both ultracentrifuge-concentrated and unconcentrated samples. For site P4 (used for recreational purposes), QMRA was applied to estimate health risks associated with exposure to E. coli and HAdV-C and F. TC and E. coli were present throughout the collection period. EV and RV were not detected. HAdV-C were present in 8.51% (1.89E + 06 to 2.28E + 07 GC (Genomic Copies)/L) and 21.27% (2.36E + 05 to 1.29E + 07 GC/L) for unconcentrated and concentrated samples, respectively. For HAdV-F were 12.76% (2.77E + 07 to 3.31E + 08 GC/L) and 48.93% (1.10E + 05 to 4.50E + 08 GC/L) for unconcentrated and concentrated samples, respectively. For unconcentrated samples, infectivity for HAdV-C was detected in 37.20% (1st ICC-qPCR) and 25.58% (2nd ICC-qPCR). For HAdV-F, infectivity was detected in 6.97% (1st ICC-qPCR) and 6.97% (2nd ICC-qPCR). For concentrated samples, HAdV-C infectious was observed in 17.02% (1st ICC-qPCR) and in 8.51% (2nd ICC-qPCR). For HAdV-F, were present in 8.51% for both 1st and 2nd ICC-qPCR. Statistical analyzes showed significant difference between the collection sites when analyzed the molecular data of HAdV-F, data of TC and E. coli. Correlation tests showed direct correlation between HAdV-F with E. coli and TC. E. coli concentrations translated to the lowest estimates of infection risks (8.58E-05 to 2.17E-03). HAdV-F concentrations were associated with the highest infection risks at 9.99E-01 and for group C, 1.29E-01 to 9.99E-01. These results show that commonly used bacterial indicators for water quality may not infer health risks associated with viruses in recreational freshwaters.

Survival of bacterial pathogens in different environments is due, in part, to their ability to form biofilms. Four wild-type Salmonella enterica strains, two Oranienburg and two Saintpaul isolated from river water and animal feces, were tested for biofilm formation at the air-liquid interface under stressful conditions (pH and salinity treatments such as pH 3, NaCl 4.5 w/v; pH 7, NaCl 4.5 w/v; pH 10, NaCl 4.5 w/v; pH 3, Nacl 0.5 w/v; pH 7, NaCl 0.5 w/v; and pH 10, NaCl 0.5 w/v); Salmonella Typhimurium DT104 was used as a control strain. Salmonella Oranienburg and Saintpaul from feces were moderately hydrophobic and motile, while S. Saintpaul from water and the control strain S. Typhimurium showed high hydrophobicity, which helped them form more resistant biofilms than S. Oranienburg. Under stressful conditions, all strains experienced difficulties in forming biofilms. Salmonella Saintpaul and Typhimurium expressed the red dry and rough (RDAR) morphotype and were able to form biofilm at air-liquid interface, contrarily to Oranienburg that showed incomplete rough morphology. This study contributes to the knowledge of biofilm formation as a survival strategy for Salmonella in aquatic environments.

This study was undertaken to identify water intake and source patterns among a population that resides in a hot, arid region on the US-Mexico border. A cross-sectional community-based survey was conducted among households in the neighbouring cities of El Paso, TX, USA and Ciudad Juárez, Chihuahua, Mexico to obtain data on the quantity and source of water consumed. The study was also designed to identify factors that impact water consumption patterns, including gender, demographics, socio-economic status, cultural characteristics, health status, types of occupations and residences, available water sources and outdoor temperature, among many others. Of all factors studied, outdoor air temperature was found to have the strongest impact upon water intake quantity. Specifically, among the survey participants, when the outdoor air temperature exceeded 90 °F, water consumption increased by 28 %. Additionally, it was found that participants in this region consumed approximately 50 % more water than the values reported in previous studies.

More than 10 years ago, food-borne pathogens were estimated to cause 76 000 illnesses and 5 000 deaths in the USA alone. Given the under-reporting of food-borne illnesses, the numbers of illnesses and deaths associated with food are actually higher. Food-borne pathogens continue to impact public health through worldwide disease outbreaks as they have many opportunities to enter the food chain - from the pre-harvest environment to the consumer. With over half of all disease-causing micro-organisms having the ability to be transmitted zoonotically, food animal production is a key source of pathogens in the farm-to-fork continuum. The protozoan parasites, Cryptosporidium and Giardia , have both been implicated in food-borne disease, and have the potential to be transmitted zoonotically in the farm environment. Farm management strategies have been developed to minimize the transmission of protozoa (from animals) that may infect farm workers, and contaminate nearby waterways and food crops. Such strategies target protecting the health of the herd, preventing (oo)cyst transmission to surface water and vegetable crops, and providing education to animal husbandry personnel and veterinarians on best management practices. To fully address the challenges associated with food safety, post-harvest control measures should also be implemented.

Untreated sewage has adversely affected the quality of marine recreational waters worldwide. Exposure to marine recreational water with poor microbial quality may pose a threat to bathers. The objectives of this study were to assess the effect of physicochemical parameters on Cryptosporidium and Giardia presence in marine recreational water of Sinaloa, Mexico, by Logistic Regression Analyses. Thirty-two 10-litre water samples were collected from two tourist beaches, Altata and Mazatlan, between November 2006 and May 2007. Water samples were processed by the EPA 1623 method and pH, temperature, salinity and turbidity were also determined. Cryptosporidium and Giardia were present in 71 and 57% of the samples collected from Altata, respectively. In Mazatlan, Cryptosporidium and Giardia were found in 83 and 72% of the samples, respectively. The overall concentration of Cryptosporidium ranged from 150 to 2,050 oocysts/10 L with an average of 581 oocysts/10 L and Giardia ranged from 10 to 300 cysts/10 L with an average of 73 cysts/10 L. The occurrence of both parasites increased in water with decreasing temperatures and increasing turbidity of the water.

Piped water is available in Ciudad Juarez, Chihuahua, Mexico, but residual disinfectant is not reliably found in the public drinking water supply. Lack of confidence in the public supply leads many residents to rely on bottled water. To provide consistent disinfection, two health clinics were equipped with ultraviolet disinfection systems, and neighboring households were encouraged to obtain their drinking water from the treatment systems. Use of the treated water declined from 62% of self-selected study participants at the time of the first visit to 40% at the second visit. During the first visit, diarrhea prevalence was similar among households using treated water and other water sources yet diarrhea prevalence was higher among households using the treated water during the second visit. Microbiological quality of the treated water in the homes was not demonstrably superior to that of other sources.

Quantitative microbial risk assessment is a useful way to predict the incidence of infection and illness within a community following exposure to pathogens. We used this risk assessment technique to determine the expected number of Salmonella infections and illnesses resulting from a drinking water – wastewater cross-connection incident using data generated from a distribution system simulator study and compared our results to a reported cross-contamination event that occurred in Pineville, Louisiana in 2000. Probabilities of infection and illness were estimated for different exposure scenarios representing different Salmonella concentrations and the characteristic varied attack rates for waterborne Salmonella. Risks of Salmonella infection range from 10% after a 1 day exposure (assuming the lower bound Salmonella concentration) to a 1-log greater risk of infection for all other scenarios, with risks of infection approximately 99% for 30 and 90 day exposure durations.

Taenia solium and T. saginata are zoonotic tapeworms of substantial medical and economic importance. Although human taeniasis is widely recognised as an endemic problem in Mexico, its presence in the United States is poorly understood. The first population-based study to estimate the prevalence of human infection with Taenia tapeworms along the Texas-Mexico border has recently been conducted. Households were interviewed in the Texan city of El Paso and in the neighbouring Ciudad Juárez, in Mexico. Faecal samples from household members were then checked for Taenia eggs by flotation and/or for Taenia copro-antigens in an ELISA. The overall prevalence of taeniasis in this border region was found to be 3% but, compared with the residents of Juárez, El Paso residents were 8.6-fold more likely to be tapeworm carriers. The interviews revealed some important differences between the two study sites, particularly the more frequent use of anthelminthic drugs on the Mexican side of the border. These findings have implications in terms of the planning of effective health-education campaigns to decrease the prevalence of taeniasis in the human populations along the Texas-Mexico border.

Quantitative risk assessment for Cryptosporidium oocysts and Giardia cysts was performed to determine the public health significance of non-potable use of tertiary treated reclaimed water. Seven reclaimed water treatment plants in the southwestern United States participated in this study. The average public exposure to oocysts and cysts was estimated, based on concentrations, recovery efficiency, viability and three exposure scenarios. The exponential dose-response model was chosen to determine the probability of infection from ingestion of various numbers of oocysts and cysts. The risks of infection for Giardia were approximately one or two orders of magnitude higher than those for Cryptosporidium. The combined risks of infection from oocysts and cysts at sites using a combination of chlorination and UV disinfection would meet the annual acceptable risk of 1.00E-04, whereas those at the other utilities using only chlorination indicated higher probability of infection than the 1.00E-04 resulting from accidental consumption of a small amount of non-potable reclaimed water.

This study evaluated user preferences among three alternative in-home water treatment technologies suitable for households relying on trucked water in El Paso County, Texas, which is on the border with Mexico. The three technologies were: chlorination of household storage tanks, small-scale batch chlorination, and point-of-use ultraviolet disinfection. Fifteen households used each of the three technologies in succession for roughly four weeks each during April through June of 2004. Data were collected on treated water quality, and a face-valid survey was administered orally to assess user satisfaction with the technologies on a variety of attributes. Treatment with a counter-top ultraviolet disinfection system received statistically significantly higher ratings for taste and odor and likelihood of future use than the other two approaches. Ultraviolet disinfection and small-scale batch chlorination both received significantly higher ratings for ease of use than did storage tank chlorination. Over-chlorination was a common problem with both batch chlorination and storage tank chlorination. Water quality in the households using trucked water is now higher than was reported by a previous study, suggesting that water quality has improved over time.Este estudio evaluó las preferencias de los consumidores de tres tecnologías domésticas para el tratamiento del agua, apropiadas para viviendas del condado de El Paso, Texas, situado en la frontera con México, que dependen del agua transportada en camiones. Las tres tecnologías fueron cloración de los tanques domésticos de almacenamiento, cloración de pequeños lotes de agua y desinfección mediante luz ultravioleta en el punto de dispensación. Quince viviendas utilizaron sucesivamente cada una de las tres tecnologías durante aproximadamente cuatro semanas entre abril y junio de 2004. Se registraron los datos sobre la calidad del agua tratada y se realizó una encuesta oral aceptada por los expertos para medir el grado de satisfacción de los usuarios con relación a diversos atributos de esas tecnologías. El tratamiento con el sistema de desinfección mediante luz ultravioleta instalado sobre la barra de la cocina tuvo una mejor valoración según el gusto y el olor del agua y una mayor probabilidad de uso futuro que los otros dos métodos. La desinfección mediante luz ultravioleta y la cloración de pequeños lotes recibieron mayor puntuación por su facilidad de uso con respecto a la cloración de los tanques de almacenamiento. La cloración excesiva fue un problema frecuente, tanto en la cloración de pequeños lotes como de los tanques de almacenamiento. La calidad del agua en las viviendas que utilizan agua transportada en camiones es ahora superior que la encontrada en estudios anteriores, lo que parece indicar que la calidad del agua ha mejorado.

Modern animal husbandry in the United States and other parts of the world has evolved the swine industry from one that was pasture based into a system based predominantly upon confinement and concentration of animals (Perez-Trallero and Zigorraga 1995; Scarpino and Quinn 1998). Most current animal production facilities rely on confined animal feeding operations (CAFOs) and the addition of subtherapeutic doses of broad-spectrum antibiotics to swine feed as a cheaper way to prevent disease and maintain production yields (Witte 1998). Antimicrobials are known to promote growth in swine and improve the efficiency of feed conversion and can affect bacterial and fungal disease prophylaxis among the confined animals (Davies and Roberts 1999). These treated animals generally gained weight 4–5% faster than other animals not given the antibiotics. Feeding animals antibiotics is associated with the development of antibiotic-resistant bacteria within these animals (Burriel 1997; Nijsten et al. 1996; Threlfall et al. 1993). Antibiotic use within food production animals has raised concern among public health authorities regarding the development of antibiotic-resistant bacteria in dosed animals and the possible subsequent impact on the health of farmworkers and others in proximity to the CAFOs (Witte 1998). Antibiotics are the leading treatment method for bacterial infectious diseases, which remain the most common cause of death worldwide (McGeer 1998). It is widely accepted that antibiotic-resistant pathogens make clinical treatment more difficult (Takafuji 1977). At local levels, areas surrounding swine production facilities might notice a rise in the difficulty of treating human health problems (Haglind and Rylander 1987). These health concerns include, but are not limited to, respiratory problems, infectious disease, and hypersensitive reactions (DuPont and Steele 1987). Those individuals who live or work in proximity to a facility spreading antibiotic-resistant bacteria could face higher exposures to these organisms (Scarpino and Quinn 1998). Gibbs et al. (2004) recovered antibiotic-resistant organisms known to have adverse human health effects both inside and downwind of the facility. It is an important next step to begin evaluating the distance these organisms can travel within bioaerosols to eventually address public health impact. The CAFO evaluated in this study was not using subtherapeutic doses of antibiotics at the time air sampling was conducted; however, the animals had received subtherapeutic levels of antibiotics 4 weeks before sampling. The primary objective of this study was to determine the levels of antibiotic-resistant bacteria, including multidrug-resistant bacteria (those resistant to at least two classes of antibiotics) found in air plumes 25 m upwind and 25, 50, 100, and 150 m downwind from a CAFO. These organisms could affect the health of those in proximity to the facility, such as employees. We hypothesized that the quantity of antibiotic-resistant bacteria would show a negative correlation with distance from the CAFO facility, which would support previous research showing that the animals within CAFOs are significant sources of antibiotic-resistant organisms (Gibbs et al. 2004).

This study evaluated prevalence of unsafe storage of toxic products and evaluated the association of demographic-socio-cultural variables with risk of young-child exposure to household poisons. Interviews were conducted with 698 low-income caregivers living on the U.S./Mexico border. Multiple-ordinal regression was used to analyze associations between very unsafe storage of toxic products and household factors. At least one toxic product was accessible to children in 49.4% of households and 18.5% of these households' stored substances very unsafely in that products were accessible and stored either in non-original containers or without childproof caps. At-risk households were associated with U.S.-born caregivers who were single, employed, and live in more U.S. acculturated communities. These homes stored an increased number of toxins and were more likely to house a smoker. U.S./Mexico border childhood poisoning prevention programs should focus on potentially acculturated families with personal and household characteristics akin to the U.S. mores and customs.

Virus contamination of the water environment through disposal of human wastewater remains a concern for the water industry. Coxsackieviruses are the most common nonpolio enteroviruses found in domestic wastewater and in contaminated surface water, groundwater, and drinking water. Although most infections result in mild febrile illness, coxsackieviruses are capable of causing a wide range of serious illnesses (including aseptic meningitis, myocarditis, and respiratory illness) and are associated with cases of insulin-dependent diabetes mellitus. A risk assessment approach was used to evaluate the potential public health effects associated with contaminated drinking water and recreational waters. An exponential model developed from human dose--response studies was used to describe the infectivity of coxsackievirus type B and estimate daily and yearly risks of infection, morbidity, and mortality. Concentrations of coxsackievirus reported in the literature were used to examine potential exposure. Although risks of infection for coxsackievirus are lower than for rotavirus, levels detected during outbreaks resulted in risks of 10 - 1 annually for drinking water. Risks assuming an ingestion of 100 mL per swim were 10 - 2 for a 10-day exposure to freshwater. The severity of the diseases associated with this type of virus and its widespread contamination emphasize the importance of maintaining reliable wastewater and drinking water treatment.