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Background: Diarrhoeal outcomes in children are often ascertained using caregiver-reported symptoms, which are subject to a variety of biases and methodological challenges. One source of bias is the time window used for reporting diarrhoeal illness and the ability of caregivers to accurately recall episodes in children.Methods: Diarrhoea period prevalence in children under five was determined using two similarly administered, nationally representative household surveys: Performance Monitoring and Accountability 2020 (PMA2020) (1-week recall, N = 14 603) and Demographic and Health Surveys (DHS) (2-week recall, N = 66 717). Countries included in the analysis were the Democratic Republic of the Congo, Ethiopia, Ghana, Kenya and Uganda. Diarrhoea period prevalence estimates were compared and water, sanitation and hygiene risk factors were analysed.Results: Childhood diarrhoea prevalence using 1-week recall (PMA2020) pooled across countries was 21.4% [95% confidence interval (CI): 19.9%, 22.9%] versus 16.0% using 2-week recall (DHS) (95% CI: 15.4%, 16.5%). In stratified analyses for all five countries, the number of diarrhoea cases detected was consistently higher using 1-week recall versus 2-week recall. The key risk factors identified in the PMA2020 data that were not associated with diarrhoeal episodes or were attenuated in the DHS data included: the main sanitation classifications for households, disposal method used for child faeces, number of household members and wealth quintiles.Conclusions: For nationally representative household surveys assessing childhood diarrhoea period prevalence, a 2-week recall period may underestimate diarrhoea prevalence compared with a 1-week period. The household sanitation facility and practices remain key risk factors for diarrhoeal disease in children under five. [ABSTRACT FROM AUTHOR]

Understanding the excretion and treatment of human waste (feces and urine) in low and middle income countries (LMICs) is necessary to design appropriate waste management strategies. However, excretion and treatment are often difficult to quantify due to decentralization of excreta management. We address this gap by developing a mechanistic, stochastic model to characterize phosphorus, nitrogen, biochemical oxygen demand (BOD), and fecal coliform pollution from human excreta for 108 LMICs. The model estimates excretion and treatment given three scenarios: (1) use of existing sanitation systems, (2) use of World Health Organization-defined "improved sanitation", and (3) use of best available technologies. Our model estimates that more than 109 kg/yr each of phosphorus, nitrogen and BOD are produced. Of this, 22(19-27)%, 11(7-15)%, 17(10-23)%, and 35 (23-47)% (mean and 95% range) BOD, nitrogen, phosphorus, and fecal coliforms, respectively, are removed by existing sanitation systems. Our model estimates that upgrading to "improved sanitation" increases mean removal slightly to between 17 and 53%. Under the best available technology scenario, only approximately 60-80% of pollutants are treated. To reduce impact of nutrient and microbial pollution on human and environmental health, improvements in both access to adequate sanitation and sanitation treatment efficiency are needed. [ABSTRACT FROM AUTHOR]

Tangential-flow ultrafiltration was optimized for the recovery of Escherichia coli, Enterococcus faecalis, Clostridium perfringens spores, bacteriophages MS2 and PRD1, murine norovirus, and poliovirus seeded into 100-liter surface water (SW) and drinking water (DW) samples. SW and DW collected from two drinking water treatment plants were then evaluated for human enteric viruses. [ABSTRACT FROM AUTHOR]

Tangential flow ultrafiltration (UF) was used to concentrate and recover bacterial indicators and enteric viruses from 100 liters of groundwater (GW; n = 10) and surface water (SW; n = 11) samples collected in Lower Yakima Valley, WA. Human and bovine enteric viruses were analyzed in SW and GW concentrates by real-time PCR by using integrated inhibition detection. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effect of aerosol generation, relative humidity, and method of sampling on the culturability of the vegetative bacteria Pantoea agglomerans (P. agglomerans) formerly known as Erwinia herbicola. This research has relevance both for the use of this organism as a biowarfare simulant and for bioaerosol exposure assessment and public health. The culturability of P. agglomerans was tested using a test chamber against two generating systems (Collison and Bubble nebulizers), two sampling systems (the all-glass impinger (AGI-30), and the BioSampler), three collection media (water, TSB, and PBS) and across a range of humidities. Results indicated that the Bubble nebulizer was 15% more efficient in generating viable P. agglomerans counts (p ≤ 0.05). No difference was observed in overall efficiency between sampling methods (p > 0.05). However, as a collection media, PBS was observed to yield higher (p ≤ 0.01) viable counts compared to sterile deionized water. Relative humidity was found to strongly influence airborne P. agglomerans culturability. Culturable P. agglomerans was below the limit of detection for RH < 15% and then increased in a log-linear fashion to humidities of 75%. This research will help identify optimal means for evaluation of environmentally sensitive airborne bacteria for purposes of exposure assessment and public health as well as homeland security. [ABSTRACT FROM AUTHOR]

Human noroviruses (NoVs) are a significant cause of nonbacterial gastroenteritis worldwide, with contaminated drinking water a potential transmission route. The absence of a cell culture infectivity model for NoV necessitates the use of molecular methods and/or viral surrogate models amenable to cell culture to predict NoV inactivation. The NoV surrogates murine NoV (MNV), feline calicivirus (FCV), poliovirus (PV), and male-specific coliphage MS2, in conjunction with Norwalk virus (NV), were spiked into surface water samples (n = 9) and groundwater samples (n = 6). Viral persistence was monitored at 25°C and 4°C by periodically analyzing virus infectivity (for all surrogate viruses) and nucleic acid (NA) for all tested viruses. FCV infectivity reduction rates were significantly higher than those of the other surrogate viruses. Infectivity reduction rates were significantly higher than NA reduction rates at 25°C (0.18 and 0.09 log10/day for FCV, 0.13 and 0.10 log10/day for PV, 0.12 and 0.06 log10/day for MS2, and 0.09 and 0.05 log10/day for MNV) but not significant at 4°C. According to a multiple linear regression model, the NV NA reduction rates (0.04 ± 0.01 log10/day) were not significantly different from the NA reduction rates of MS2 (0.05 ± 0.03 log10/day) and MNV (0.04 ± 0.03 log10/day) and were significantly different from those of FCV (0.08 ± 0.03 log10/day) and PV (0.09 ± 0.03 log10/day) at 25°C. In conclusion, MNV shows great promise as a human NoV surrogate due to its genetic similarity and environmental stability. FCV was much less stable and thus questionable as an adequate surrogate for human NoVs in surface water and groundwater. [ABSTRACT FROM AUTHOR]

The city of New Orleans, LA was severely impacted by flooding and wind damage following landfall of Hurricane Katrina in August 2005. The city's drinking water infrastructure was severely compromised and massive amounts of sediment were redeposited throughout the flooded region. Thousands of homes were water-damaged resulting in the rapid growth of mold. In September and October 2005 a convenience sample of selected homes, tap water, surface water, and sediment within New Orleans was assessed for mold contamination, microbial contamination, and heavy metal concentrations. At selected sites, indoor mold spore concentrations were compared to outdoor concentrations. The purpose of this study was to conduct a baseline environmental assessment in an effort to identify public health threats caused by wind and flood damage. Surface waters contained high concentrations of bacterial indicators whereas no bacteria were detected in tap water, even from taps containing no chlorine residual. Sediment samples contained concentrations of lead and arsenic similar to pre-Katrina concentrations. Outdoor total spore (sp) concentrations ranged from >6500 to 84 713 sp/m³. Indoor concentrations ranged from 6142 to 735 123 sp/m³. For the 13 locations with matched indoor/outdoor samples, the mean indoor/outdoor spore ratio was 4.11 (ranging from 0.27 to >11.44). Inside 5 of the 13 homes, total spore counts/m³ exceeded 100 000, with measurements in the moldiest home exceeding 700 000 sp/m³. In conclusion, surface waters had high concentrations of bacterial contamination but no bacterial indicators were present in tap water. Sediment samples did not have appreciable increases in lead or arsenic. Flooded homes, however, contained substantial concentrations of mold which could present a public health exposure route to individuals repopulating and restoring the City of New Orleans. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) represents a rapid technique for the identification of microbial monocultures, and its adaptation to the detection of pathogens in real-world samples is a public health and homeland security priority. Norovirus, a leading cause of gastroenteritis in the world, is difficult to monitor because it cannot be cultured outside the human body. The detection of norovirus capsid protein was explored using three common MS-based methods: scanning of intact proteins, peptide mass fingerprinting, and peptide sequencing. Detection of intact target protein was limited by poor selectivity and sensitivity. Detection of up to 16 target peptides by peptide mass fingerprinting allowed for the reproducible and confident (P < 0.05) detection of the 56-kDa norovirus capsid protein in the range of 0.1 × 10-12 to 50 × 10-12 mol in authentic standards of recombinant norovirus virus-like particles (VLPs). To explore assay performance in complex matrixes, a non-gel-based, rapid method (2 to 3 h) for virus extraction from human stool was evaluated (72% ± 12% recovery), and additional analyses were performed on norovirus-free stool extracts fortified with VLPs. Whereas peptide mass fingerprinting was rendered impractical by sample interferences, peptide sequencing using nanospray tandem MS facilitated unambiguous identification of >250 fmol of capsid protein in stool extracts. This is the first report on MS-based detection of norovirus, accomplished by using structurally identical, noninfective VLPs at clinically relevant concentrations. It represents an important milestone in the development of assays for surveillance of this category B bioterrorism agent. [ABSTRACT FROM AUTHOR]

Rapidly growing populations and migration to urban areas in developing countries has resulted in a vital need for the establishment of centralized water systems to disseminate potable water to residents. Protected source water and modern, well-maintained drinking water treatment plants can provide water adequate for human consumption. However, ageing, stressed or poorly maintained distribution systems can cause the quality of piped drinking water to deteriorate below acceptable levels and pose serious health risks. This review will outline distribution system deficiencies in developing countries caused by: the failure to disinfect water or maintain a proper disinfection residual; low pipeline water pressure; intermittent service; excessive network leakages; corrosion of parts; inadequate sewage disposal; and inequitable pricing and usage of water. Through improved research, monitoring and surveillance, increased understanding of distribution system deficiencies may focus limited resources on key areas in an effort to improve public health and decrease global disease burden. [ABSTRACT FROM AUTHOR]

Infections caused by Toxoplasma gondii are widely prevalent in animals and humans throughout the world. In the United States, an estimated 23% of adolescents and adults have laboratory evidence of T. gondii infection. T. gondii has been identified as a major opportunistic pathogen in immunocompromised individuals, in whom it can cause life-threatening disease. Water contaminated with feces from domestic cats or other felids may be an important source of human exposure to T. gondii oocysts. Because of the lack of information regarding the prevalence of T. gondii in surface waters, there is a clear need for a rapid, sensitive method to detect T. gondii from water. Currently available animal models and cell culture methods are time-consuming, expensive, and labor-intensive, requiring days or weeks for results to be obtained. Detection of T. gondii nucleic acid by PCR has become the preferred method. We have developed a PCR amplification and detection method for T. gondii oocyst nucleic acid that incorporates the use of hot-start amplification to reduce nonspecific primer annealing, uracii-N-glycosylase to prevent false-positive results due to carryover contamination, an internal standard control to identify false-negative results due to inadequate removal of sample inhibition, and PCR product oligoprobe confirmation using a nonradioactive DNA hybridization immunoassay. This method can provide positive, confirmed results in less than 1 day. Fewer than 50 oocysts can be detected following recovery of oocyst DNA. Development of a T. gondii oocyst PCR detection method will provide a useful technique to estimate the levels of T. gondii oocysts present in surface waters. [ABSTRACT FROM AUTHOR]

Reports on the development of a reverse transcription-PCR-DNA enzyme immunoassay for detection of 'norwalk-like' viruses and hepatitis A virus in stool and shellfish. Main cause of outbreaks of food- and waterborne gastroenteritis; Principles of the developed method; General applicability of the developed method in the detection of viruses.

Focuses on methods for the detection of Norwalk-like viruses (NLV) and hepatitis A virus (HAV) in delicatessen foods. Isolation and purification of NLV from deli meats; Detection of genogroup II NLV in ham using polymerase- and capsid-specific primers and probes; Similarity of capsid sequences from stool and ham samples.

BACKGROUND: Chronic arsenic exposure has been associated with an increased risk of cardiovascular disease; diabetes; cancers of the lung, pancreas and prostate; and all-cause mortality in American Indian communities in the Strong Heart Study. OBJECTIVE: The Strong Heart Water Study (SHWS) designed and evaluated a multilevel, community-led arsenic mitigation program to reduce arsenic exposure among private well users in partnership with Northern Great Plains American Indian Nations. METHODS: A cluster randomized controlled trial (cRCT) was conducted to evaluate the effectiveness of the SHWS arsenic mitigation program over a 2-y period on a) urinary arsenic, and b) reported use of arsenic-safe water for drinking and cooking. The cRCT compared the installation of a pointof- use arsenic filter and a mobile Health (mHealth) program (3 phone calls; SHWS mHealth and Filter arm) to a more intensive program, which included this same program plus three home visits (3 phone calls and 3 home visits; SHWS Intensive arm). RESULTS: A 47% reduction in urinary arsenic [geometric mean (GM)=13.2 to 7.0 μg/g creatinine] was observed from baseline to the final follow-up when both study arms were combined. By treatment arm, the reduction in urinary arsenic from baseline to the final follow-up visit was 55% in the mHealth and Filter arm (GM=14.6 to 6.55 μg/g creatinine) and 30% in the Intensive arm (GM=11.2 to 7.82 μg/g creatinine). There was no significant difference in urinary arsenic levels by treatment arm at the final follow-up visit comparing the Intensive vs. mHealth and Filter arms: GM ratio of 1.21 (95% confidence interval: 0.77, 1.90). In both arms combined, exclusive use of arsenic-safe water from baseline to the final follow-up visit significantly increased for water used for cooking (17% to 53%) and drinking (12% to 46%). DISCUSSION: Delivery of the interventions for the community-led SHWS arsenic mitigation program, including the installation of a point-of-use arsenic filter and a mHealth program on the use of arsenic-safe water (calls only, no home visits), resulted in a significant reduction in urinary arsenic and increases in reported use of arsenic-safe water for drinking and cooking during the 2-y study period. These results demonstrate that the installation of an arsenic filter and phone calls from a mHealth program presents a promising approach to reduce water arsenic exposure among private well users. [ABSTRACT FROM AUTHOR]

Background: The lack of established measurement tools in the study of menstrual health and hygiene has been a significant limitation of quantitative studies to date. However, there has been limited exploration of existing measurement to identify avenues for improvement. Methods: We undertook two linked systematic reviews of (1) trials of menstrual health interventions and their nested studies in low- and middle-income countries, (2) studies developing or validating measures of menstrual experiences from any location. Systematic searching was undertaken in 12 databases, together with handsearching. We iteratively grouped and audited concepts measured across included studies and extracted and compared measures of each concept. Results: A total of 23 trials, 9 nested studies and 22 measure development studies were included. Trials measured a range of outcomes including menstrual knowledge, attitudes, and practices, school absenteeism, and health. Most measure validation studies focused on assessing attitudes towards menstruation, while a group of five studies assessed the accuracy of women's recall of their menstrual characteristics such as timing and cycle length. Measures of menstrual knowledge, attitudes, beliefs and restrictions were inconsistent and frequently overlapped. No two studies measured the same menstrual or hygiene practices, with 44 different practices assessed. This audit provides a summary of current measures and extant efforts to pilot or test their performance. Conclusions: Inconsistencies in both the definition and operationalisation of concepts measured in menstrual health and hygiene research should be addressed. To improve measurement, authors should clearly define the constructs they aim to measure and outline how these were operationalised for measurement. Results of this audit indicate the need for the development and validation of new measures, and the evaluation of the performance of existing measures across contexts. In particular, the definition and measurement of menstrual practices, knowledge, attitudes, norms and restrictions should be addressed. Review protocol registration: CRD42018089884. [ABSTRACT FROM AUTHOR]

Inadequate menstrual hygiene presents a barrier to women's dignity and health. Recent attention to this marginalised challenge has resulted in the first national assessments of menstrual practices. Intuitively, surveys require women to have had a recent menses to be eligible. This study seeks to determine if there are demographic differences between women who are eligible and ineligible to answer questions about their menstrual hygiene during these assessments. Secondary analyses were undertaken on nationally or state representative data collected by the Performance Monitoring and Accountability 2020 survey programme across eight countries (Burkina Faso, Ethiopia, Ghana, India, Kenya, Niger, Nigeria, and Uganda). Female respondents were included in the study and compared on whether they had a menstrual period within the past three months and thus were eligible to answer questions regarding menstrual practices. On average, 29% of surveyed women across samples were ineligible to be asked menstrual hygiene questions. Higher levels of education, wealth, and urban residence were associated with higher odds of eligibility. Young and unmarried women were also more likely to be eligible. Demographic differences between eligible and ineligible women were consistent across all countries. Wealthy, urban, and educated women are more likely to be eligible to answer survey questions about menstrual hygiene. While population surveys may be representative of menstruating women, proportions of menstrual hygiene practices reported underrepresent the experiences of more vulnerable groups. These groups are likely to have greater struggles with menstrual hygiene when they are menstruating. [ABSTRACT FROM AUTHOR]

Background: Women worldwide experience challenges managing their periods. Menstrual and genital hygiene behaviours have been linked to negative health outcomes, including urogenital symptoms and confirmed infections. However, evidence testing this association has been limited and mixed. This study aimed to (1) describe the menstrual care practices and prevalence of self-reported urogenital symptoms among working women in Mukono District, Uganda, and (2) test the associations between menstrual and genital care practices, and urogenital symptoms. Methodology: We undertook a cross-sectional survey of women aged 18–45 working in markets, schools, and healthcare facilities in Mukono District, with 499 participants who had menstruated in the past two months included in this analysis. We developed an aggregated measure of menstrual material cleanliness, incorporating material type and laundering practices. Associations with urogenital symptoms were tested using the aggregated material cleanliness measure alongside the frequency of changing materials, handwashing before menstrual tasks, and sanitation practices. Results: Among our sample, 41% experienced urogenital symptoms in the past month. Compared to women exclusively using disposable pads, using appropriately cleaned or non-reused improvised materials (PR = 1.33, 95%CI 1.04–1.71), or inadequately cleaned materials (improvised or commercially produced reusable pads) (PR = 1.84, 95%CI 1.46–3.42) was associated with an increased prevalence of self-reported urogenital symptoms in the last month. There was no difference between those using disposable pads and those using clean reusable pads (PR = 0.98; 95%CI 0.66–1.57). Infrequent handwashing before changing materials (PR 1.18, 95%CI: 0.96–1.47), and delaying urination at work (PR = 1.37, 95%CI: 1.08–1.73) were associated with an increased prevalence of self-reported symptoms. Conclusion: Prevalence of self-reported urogenital symptoms was associated with the type and cleanliness of menstrual material used as well as infrequent handwashing and urinary restriction. There is a need for interventions to enable women to maintain cleanliness of their menstrual materials and meet their menstruation, urination and hand washing needs at home and work. [ABSTRACT FROM AUTHOR]

Peracetic acid (PAA) is a strong oxidant/bactericide that has been applied in various industries ( e.g. , food processing, pharmaceuticals, medical device sterilization, etc.) as a disinfectant. There is increasing interest in using PAA for wastewater disinfection because it does not form halogenated byproducts, and no post-treatment quenching is required. Previous studies have demonstrated good efficiency in controlling bacteria in wastewater, but limited information is available for viruses, especially those hosted by mammals ( e.g. , norovirus). Therefore, a study on the infectivity reduction of murine norovirus (MNV) was undertaken to evaluate the disinfection efficacy of PAA or UV alone and in combination with UV irradiation in undisinfected secondary effluent from a municipal wastewater reclamation facility (MWW) and phosphate buffer solution (PBS) at pH 7. Experiments employing MS2 bacteriophage were also performed in parallel for comparison purposes. MS2 infectivity reduction was found to be lower than MNV infectivity reduction for each condition studied – PAA, PAA + UV, and UV disinfection. These data suggest that MS2 may not be an appropriate surrogate to accurately predict the reduction of MNV infectivity. UV irradiation, in a dose range of 5–250 mJ/cm 2 , provided linear log inactivation (-log (N/N 0 )) with a regression slope (cm 2 mJ −1 ) of 0.031–0.034 and 0.165–0.202 for MS2 and MNV, respectively. UV irradiation provided similar inactivation for MS2 and MNV in both suspensions (PBS or MWW). Low infectivity reduction of MS2 was observed when PAA was used alone at a practical dose of 1.5 mg/L and below. A greater reduction of both MNV and MS2 was observed in PAA disinfection experiments using PBS as the microbial suspension medium, than in secondary effluent. Similar results were observed in PAA + UV experiments, in which greater synergistic effects were found in PBS than in MWW. Results of OH radical formation experiments suggest the presence of radical scavengers in MWW, which resulted in less opportunity for MNV and MS2 to encounter OH radicals. This study also demonstrated that the type of water can have a substantial impact on wastewater disinfection when employing PAA or PAA + UV treatment due to the matrix effect and the presence of radical scavengers, respectively. The results from this study could be employed to aid in the conceptual design of PAA and UV disinfection facilities, especially when norovirus is the organism of concern. [ABSTRACT FROM AUTHOR]

Chlorination has long been used for disinfection of municipal wastewater (MWW) effluent while the use peracetic acid (PAA) has been proposed more recently in the United States. Previous work has demonstrated the bactericidal effectiveness of PAA and monochloramine in wastewater, but limited information is available for viruses, especially ones of mammalian origin (e.g., norovirus). Therefore, a comparative assessment was performed of the virucidal efficacy of PAA and monochloramine against murine norovirus (MNV) and MS2 bacteriophage in secondary effluent MWW and phosphate buffer (PB). A suite of inactivation kinetic models was fit to the viral inactivation data. Predicted concentration-time (CT) values for 1-log10 MS2 reduction by PAA and monochloramine in MWW were 1254 and 1228 mg-min/L, respectively. The 1-, 2-, and 3-log10 model predicted CT values for MNV viral reduction in MWW were 32, 47, and 69 mg-min/L for PAA and 6, 13, and 28 mg-min/L for monochloramine, respectively. Wastewater treatment plant disinfection practices informed by MS2 inactivation data will likely be protective for public health but may overestimate CT values for reduction of MNV. Additionally, equivalent CT values in PB resulted in greater viral reduction which indicate that viral inactivation data in laboratory grade water may not be generalizable to MWW applications. [ABSTRACT FROM AUTHOR]

Norovirus infections are one of the most prominent public health problems of microbial origin in the U.S. and other industrialized countries. Surveillance is necessary to prevent secondary infection, confirm successful cleanup after outbreaks, and track the causative agent. Quantitative mass spectrometry, based on absolute quantitation with stable-isotope labeled peptides, is a promising tool for norovirus monitoring because of its speed, sensitivity, and robustness in the face of environmental inhibitors. In the current study, we present two new methods for the detection of the norovirus genogroup I capsid protein using electrospray and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The peptide TLDPIEVPLEDVR was used to quantify norovirus-like particles down to 500 attomoles with electrospray and 100 attomoles with MALDI. With MALDI, we also demonstrate a detection limit of 1 femtomole and a quantitative dynamic range of 5 orders of magnitude in the presence of an environmental matrix effect. Due to the rapid processing time and applicability to a wide range of environmental sample types (bacterial lysate, produce, milk, soil, and groundwater), mass spectrometry-based absolute quantitation has a strong potential for use in public health and environmental sciences. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic ion exchange (MIEX) pretreatment has been increasingly employed by water treatment plants for removal of dissolved organic carbon (DOC). In this study, the effects of MIEX pretreatment on low pressure membrane filtration of natural surface water were investigated under different feedwater qualities, membrane properties, and MIEX dosing conditions. Regardless of feedwater DOC, moderate decrease in the total and hydraulically irreversible fouling was observed for a polyvinylidene fluoride (PVDF) microfiltration membrane and a polyethersulfone ultrafiltration (UF) membrane after MIEX pretreatment, which was coincident with moderate removals of high molecular weight DOC in the feedwaters. Comparatively, the fouling of a PVDF UF membrane did not decrease after MIEX pretreatment, revealing the impact of membrane properties on membrane fouling in the presence of MIEX pretreatment. Reuse of virgin or regenerated MIEX resulted in similar membrane fouling as observed with single use of the virgin MIEX. The level of DOC removal by MIEX was similar to the removal of MS2 bacteriophage spiked in the feedwater, suggesting a potential similarity in the removal of organic and microbial particles. In conclusion, MIEX pretreatment was effective for DOC removal, but less effective in controlling short-term membrane fouling or removing viruses. [Copyright &y& Elsevier]

Abstract: As available drinking water supplies are increasingly strained, use of low pressure membranes (LPMs 1 [1] Low pressure membranes (LPMs). ) for wastewater reuse has become more widespread. Control of viruses in reclaimed water is critical to the protection of public health. The interaction between viruses, water chemistry and membrane properties plays an important role in the organism''s removal, especially when its size is smaller than the size of reported membrane pores. Using MS2 bacteriophage as an indicator organism, the log removal value (LRV 2 [2] Log removal value (LRV). ) of the virus in waters containing secondary effluent organic matter increased with filtration time and concentration of high molecular weight organic foulants. The LRV increased from 2.1 to 3.0 for high fouling water, while removal in low fouling water ranged from 0.8 to 1.7. In comparison, a LRV of 1.0 was achieved in model water prepared to simulate a non-fouling condition. Addition of equal ionic strength of either sodium or calcium to model water reduced the LRV from 2.5 to 1.6 for sodium and to 0.9 for calcium. Mechanisms are proposed to explain the complexity of the observed membrane virus exclusion. The data in this study show that the use of pretreatment to reduce membrane fouling may ultimately impair virus removal efficiency. [Copyright &y& Elsevier]

Decentralized membrane filtration systems (DMFS) have the potential to supply safe drinking water in low-income countries (LICs) where centralized municipal water treatment is practically infeasible. This study aimed at applying an integrated bench-scale and field-testing approach to assess the sustainability of a DMFS in producing safe drinking water in LICs. The state-of-the-art DMFS employed in this study was capable of removing bacteria, surrogate parasites, and viruses at log reductions above 7, 5, and 4, respectively, from evaluated waters (n=4). The technological sustainability of the DMFS was primarily affected by membrane fouling, and a linear correlation was found between the reversible/irreversible fouling rates of a miniature bench-scale system and those of the full-size DMFS caused by representative types of source waters. The total and irreversible fouling rates of the full-size DMFS were approximately 50% of those of the miniature system, regardless of the properties of the source waters. Similar quantitative relationships may be established between the fouling rates of the bench-scale system and those of other full-size DMFS. Overall, easy and cost-effective fouling control is warranted for sustainable application of DMFS in LICs, and bench-scale membrane testing serves as a potential screening tool for this purpose. [ABSTRACT FROM AUTHOR]

To examine the long-term infectivity of human norovirus in water, 13 study subjects were challenged at different time points with groundwater spiked with the prototype human norovirus, Norwalk virus. Norwalk virus spiked in groundwater remained infectious after storage at room temperature in the dark for 61 days (the last time point tested). The Norwalk virus-seeded groundwater was stored for 1,266 days and analyzed, after RNase treatment, by reverse transcription-quantitative PCR (RT-qPCR) to detect Norwalk virus RNA contained within intact capsids. Norwalk virus RNA within intact capsids was detected in groundwater for 1,266 days, with no significant log10 reduction throughout 427 days and a significant 1.10-log10 reduction by day 1266. Purified Norwalk virus RNA (extracted from Norwalk virus virions) persisted for 14 days in groundwater, tap water, and reagent-grade water. This study demonstrates that Norwalk virus in groundwater can remain detectable for over 3 years and can remain infectious for at least 61 days. [ABSTRACT FROM AUTHOR]

Crassostrea ariakensis oysters are under review for introduction into the Chesapeake Bay. However, the human health implications of the introduction have not been fully addressed. This study evaluated rates of bioaccumulation, retention, and depuration of viruses by Crassostrea virginica and C. ariakensis when the two oyster species were maintained in separate tanks containing synthetic seawater of various salinities (8, 12, or 20 ppt). Oyster bioaccumulation tanks were seeded with 103 PFU/ml of hepatitis A virus (HAV), poliovirus, male-specific bacteriophage (MS2), and murine norovirus 1 (MNV-1) and 103 PCR units/mI of human norovirus (NoV). After 24 h, depuration commenced as oysters (n = 255) were placed in pathogen-free seawater under continuous filtration. Oysters (n = 6) were sampled weekly for 1 month from each tank. Viral RNA was recovered using a modified proteinase K, guanidine, and glassmilk method and analyzed by quantitative reverse transcription-PCR. The odds of C. ariakensis oysters harboring NoV, MNV-1, or HAV were statistically greater than the odds of C. virginica oysters harboring the same viruses (MNV-1 odds ratio [OR], 4.5; P = 0.01; NoV OR, 8.4; P < 0.001; HAV OR, 11.4; P < 0.001). Unlike C. virginica, C. ariakensis bioaccumulated and retained NoV, MNV-1, and HAY for 1 month at all salinities. Additionally, the odds of an oyster testing positive for NoV was 25.5 times greater (P < 0.001) when the oyster also tested positive for MNV-1. This research helps assess the threat of C. ariakensis as a vehicle for viral pathogens due to the consumption of raw oysters and validates the role for MNV-1 as a surrogate for NoV. [ABSTRACT FROM AUTHOR]

Cryptosporidiosis, giardiasis and microsporidiosis are serious human diseases of waterborne origin; their etiologic agents and a substantial fecal coliform load can enter surface, drinking and recreational water resources from aquatic birds. The aim of this article is to present interactions between waterfowl and these waters that imply a negative public health impact, reinforcing the need for either better water-quality indicators or for water monitoring specifically for Cryptosporidium, Giardia and microsporidia. Where justifiable, the presence of waterfowl should be supported; however, management of drinking and recreational water resources needs to be improved by incorporating effective protection measures for pathogens linked to these birds. [Copyright &y& Elsevier]

Reports of school and work absences due to unmet menstrual needs have prompted increased attention to menstruation in policy and practice. However, there appear to be few quantitative studies reported in published literature capturing the prevalence of this hypothesised absenteeism. This study undertook secondary analysis of nationally representative Performance Monitoring and Accountability 2020 (PMA2020) data from Burkina Faso and Nigeria, and city-representative data from Niamey, Niger to determine the extent of women's and girls' self-reported absence from school and work due to menstruation. Among women and adolescent girls aged 15–49 years who had worked outside the household in the past month in Burkina Faso (n = 998), Niger (n = 212) and Nigeria (n = 3638), 19%, 11% and 17%, respectively, reported missing work due to menstruation. Among those aged 15–24 years who attended school in the past year in Burkina Faso (n = 461), Niger (n = 213) and Nigeria (n = 1574), 17%, 15% and 23% reported missing school in the past year due to menstruation. Findings support the assertion that menstruation is a source of absenteeism in West Africa and indicate that greater attention from research, practice, and policy is needed. In presenting this data we also reflect critically on the performance of questions regarding menstrual-related absenteeism in national monitoring surveys. Future monitoring efforts should consider the interpretability of similar survey data when many respondents did not attend any school or work and were ineligible to answer questions regarding absenteeism. Further, without additional research identifying the reasons for absenteeism, findings from similar survey questions may be difficult to interpret with relevance for policy decision making. [ABSTRACT FROM AUTHOR]

Foodborne contamination and associated illness in the United States is responsible for an estimated 48 million cases per year. Increased food demand, global commerce of perishable foods, and the growing threat of antibiotic resistance are driving factors elevating concern for food safety. Foodborne illness is often associated with fresh-cut, ready-to-eat produce commodities due to the perishable nature of the product and relatively minimal processing from farm to the consumer. The research presented here optimizes and evaluates the utility of microfluidic droplets, also termed ultra-miniaturized bioreactors, for rapid detection of viable Salmonella enterica ser. Typhimurium in a shredded lettuce wash water acquired from a major Mid-Atlantic produce processing facility (denoted as Producer) in the U.S. Using a fluorescently-labeled anti-S. Typhimurium antibody and relative fluorescence intensities, paired with in-droplet incubation, S. Typhimurium was detected and identified with 100% specificity in less than 5 h. In initial optimization experiments using S. Typhimurium-spiked sterile water, the relative fluorescence intensity of S. Typhimurium was approximately two times that of the observed relative intensities of five non-S. Typhimurium negative controls at 4-h incubation in droplets containing Rappaport-Vasiliadis (RV) broth at 37°C: relative fluorescence intensity for S. Typhimurium = 2.36 (95% CI: 2.15–2.58), Enterobacter aerogens 1.12 (95% CI: 1.09–1.16), Escherichia coli 700609 = 1.13 (95% CI: 1.09–1.17), E. coli 13706 1.13 (95% CI: 1.07–1.19), E. coli 700891 1.05 (95% CI: 1.03–1.07) and Citrobacter freundii 1.04 (95% CI: 1.03–1.05). S. Typhimurium- and E. aerogens-spiked shredded lettuce wash waters acquired from the Producer were then incubated 4 h in-droplet at 37°C with RV broth. The observed relative fluorescence of S. Typhimurium was significantly higher than that of E. aerogens, 1.56 (95% CI: 1.42–1.71) and 1.10 (95% CI: 1.08–1.12), respectively. While further optimization focusing on compatible concentration methodologies for highly-dilute produce water samples is needed, this application of droplet microfluidics shows great promise in dramatically shortening the time necessary–from days to hours–to confirm viable bacterial contamination in ready-to-eat produce wash waters used throughout the domestic and international food industry. [ABSTRACT FROM AUTHOR]

High-quality evidence is needed to inform policies and programmes aiming to improve menstrual health. Quantitative studies must address the many evidence gaps in this field, and practitioners have increased monitoring and evaluation efforts to track their progress. A significant barrier to improving the rigor of this work is the lack of comprehensive and comparable measures to capture core concepts. The Menstrual Practices Questionnaire (MPQ) is a new tool to support comprehensive and standardised assessment of the activities undertaken in order to collect, contain, and remove menstrual blood from the body in self-report surveys. The questionnaire is freely available online for download and can be adapted for use across contexts and age groups. In this article, we describe the purpose of the MPQ as a best-practice tool to align the description of menstrual practices and provide a foundation for further question refinement. We outline the development of the tool using systematic review of qualitative studies of menstrual experiences, audit of measures used in the study of menstrual health and hygiene, survey of experts, insights from past research, and examples from piloted questions in a survey of adolescent girls in Soroti, Uganda. We describe the identification of menstrual practices as a priority for measurement, coverage of practices included in the MPQ, and justify the inclusion of location-specific questions. For each section of the questionnaire, we outline key reasons for the inclusion of practice items alongside elaboration for users to help inform item selection. Finally, we outline priorities for future research to refine the assessment and reporting of menstrual practices, including the identification of minimum reporting requirements for population characteristics to facilitate comparison across studies, testing the extent to which experiences during the most recent menstrual period reflect those over longer time periods, and further exploration of biases in self-report. [ABSTRACT FROM AUTHOR]

High-quality evidence is needed to inform policies and programmes aiming to improve menstrual health. Quantitative studies must address the many evidence gaps in this field, and practitioners have increased monitoring and evaluation efforts to track their progress. A significant barrier to improving the rigor of this work is the lack of comprehensive and comparable measures to capture core concepts. The Menstrual Practices Questionnaire (MPQ) is a new tool to support comprehensive and standardised assessment of the activities undertaken in order to collect, contain, and remove menstrual blood from the body in self-report surveys. The questionnaire is freely available online for download and can be adapted for use across contexts and age groups. In this article, we describe the purpose of the MPQ as a best-practice tool to align the description of menstrual practices and provide a foundation for further question refinement. We outline the development of the tool using systematic review of qualitative studies of menstrual experiences, audit of measures used in the study of menstrual health and hygiene, survey of experts, insights from past research, and examples from piloted questions in a survey of adolescent girls in Soroti, Uganda. We describe the identification of menstrual practices as a priority for measurement, coverage of practices included in the MPQ, and justify the inclusion of location-specific questions. For each section of the questionnaire, we outline key reasons for the inclusion of practice items alongside elaboration for users to help inform item selection. Finally, we outline priorities for future research to refine the assessment and reporting of menstrual practices, including the identification of minimum reporting requirements for population characteristics to facilitate comparison across studies, testing the extent to which experiences during the most recent menstrual period reflect those over longer time periods, and further exploration of biases in self-report. [ABSTRACT FROM AUTHOR]

Background: To improve schistosomiasis control programs in Uganda, where intestinal schistosomiasis is a widespread public health problem, a country-wide assessment of the disease prevalence among all age ranges is needed. Few studies have aimed to quantify the relationships between disease prevalence and water and sanitation characteristics across Uganda to understand the potential to interrupt disease transmission with an integrated package of interventions. Methodology/Principal findings: A nationally representative survey was undertaken that included a household and individual questionnaire followed by disease testing based on detection of worm antigens (circulating cathodic antigen–CCA), diagnosis and treatment. A comprehensive set of questions was asked of randomly sampled individuals, two years of age and above, to understand their water and sanitation infrastructure, open defecation behaviors, exposure to surface water bodies, and knowledge of schistosomiasis. From a set of 170 randomly sampled, geographically diverse enumeration areas, a total of 9,183 study participants were included. After adjustment with sample weights, the national prevalence of schistosomiasis was 25.6% (95% confidence interval (CI): 22.3, 29.0) with children ages two to four most at risk for the disease with 36.1% infected (95% CI: 30.1, 42.2). The defecation behaviors of an individual were more strongly associated with infection status than the household water and sanitation infrastructure, indicating the importance of incorporating behavior change into community-led total sanitation coverage. Conclusions/Significance: Our results highlight the importance of incorporating monitoring and evaluation data into control programs in Uganda to understand the geographic distribution of schistosomiasis prevalence outside of communities where endemicity is known to be high. The high prevalence of schistosomiasis among the youngest age group, ineligible to receive drug treatment, shows the imperative to develop a child-appropriate drug protocol that can be safely administered to preschool-aged children. Water and sanitation interventions should be considered an essential investment for elimination alongside drug treatment. [ABSTRACT FROM AUTHOR]

Background: Attention to women's and girls' menstrual needs is critical for global health and gender equality. The importance of this neglected experience has been elucidated by a growing body of qualitative research, which we systematically reviewed and synthesised.Methods and Findings: We undertook systematic searching to identify qualitative studies of women's and girls' experiences of menstruation in low- and middle-income countries (LMICs). Of 6,892 citations screened, 76 studies reported in 87 citations were included. Studies captured the experiences of over 6,000 participants from 35 countries. This included 45 studies from sub-Saharan Africa (with the greatest number of studies from Kenya [n = 7], Uganda [n = 6], and Ethiopia [n = 5]), 21 from South Asia (including India [n = 12] and Nepal [n = 5]), 8 from East Asia and the Pacific, 5 from Latin America and the Caribbean, 5 from the Middle East and North Africa, and 1 study from Europe and Central Asia. Through synthesis, we identified overarching themes and their relationships to develop a directional model of menstrual experience. This model maps distal and proximal antecedents of menstrual experience through to the impacts of this experience on health and well-being. The sociocultural context, including menstrual stigma and gender norms, influenced experiences by limiting knowledge about menstruation, limiting social support, and shaping internalised and externally enforced behavioural expectations. Resource limitations underlay inadequate physical infrastructure to support menstruation, as well as an economic environment restricting access to affordable menstrual materials. Menstrual experience included multiple themes: menstrual practices, perceptions of practices and environments, confidence, shame and distress, and containment of bleeding and odour. These components of experience were interlinked and contributed to negative impacts on women's and girls' lives. Impacts included harms to physical and psychological health as well as education and social engagement. Our review is limited by the available studies. Study quality was varied, with 18 studies rated as high, 35 medium, and 23 low trustworthiness. Sampling and analysis tended to be untrustworthy in lower-quality studies. Studies focused on the experiences of adolescent girls were most strongly represented, and we achieved early saturation for this group. Reflecting the focus of menstrual health research globally, there was an absence of studies focused on adult women and those from certain geographical areas.Conclusions: Through synthesis of extant qualitative studies of menstrual experience, we highlight consistent challenges and developed an integrated model of menstrual experience. This model hypothesises directional pathways that could be tested by future studies and may serve as a framework for program and policy development by highlighting critical antecedents and pathways through which interventions could improve women's and girls' health and well-being.Review Protocol Registration: The review protocol registration is PROSPERO: CRD42018089581. [ABSTRACT FROM AUTHOR]

Background: Norovirus is a leading cause of acute gastroenteritis worldwide. Routine norovirus diagnosis requires stool collection. The goal of this study was to develop and validate a noninvasive method to diagnose norovirus to complement stool diagnostics and to facilitate studies on transmission.Methods: A multiplex immunoassay to measure salivary immunoglobulin G (IgG) responses to 5 common norovirus genotypes (GI.1, GII.2, GII.4, GII.6, and GII.17) was developed. The assay was validated using acute and convalescent saliva samples collected from Peruvian children <5 years of age with polymerase chain reaction (PCR)-diagnosed norovirus infections (n = 175) and controls (n = 32). The assay sensitivity and specificity were calculated to determine infection status based on fold rise of salivary norovirus genotype-specific IgG using norovirus genotype from stool as reference.Results: The salivary assay detected recent norovirus infections and correctly assigned the infecting genotype. Sensitivity was 71% and specificity was 96% across the evaluated genotypes compared to PCR-diagnosed norovirus infection.Conclusions: This saliva-based assay will be a useful tool to monitor norovirus transmission in high-risk settings such as daycare centers or hospitals. Cross-reactivity is limited between the tested genotypes, which represent the most commonly circulating genotypes. [ABSTRACT FROM AUTHOR]

Noroviruses cause significant global health burdens and waterborne transmission is a known exposure pathway. Chlorination is the most common method of disinfection for water and wastewater worldwide. The purpose of this study was to investigate the underlying causes for discrepancies in human norovirus (hNoV) resistance to free chlorine that have been previously published, and to assess hNoV GI and GII persistence during disinfection of municipal secondary wastewater (WW) effluent. Our results reveal that choice of hNoV purification methodology prior to seeding the viruses in an experimental water matrix influences disinfection outcomes in treatment studies. Common hNoV purification processes such as solvent extraction and 0.45-μm filtration were ineffective in removing high levels of organics introduced into water or wastewater samples when seeding norovirus positive stool. These methods resulted in experimental water matrices receiving an additional 190 mg/L as Cl 2 of 15-s chlorine demand and approximately 440 mg/L as Cl 2 of 30-min chlorine demand due to seeding norovirus positive stool at 1% w/v. These high organic loads impact experimental water chemistry and bias estimations of hNoV persistence. Advanced purification of norovirus positive stool using sucrose cushion ultracentrifugation and ultrafiltration reduced 15-s chlorine demands by 99% and TOC by 93% for loose (i.e. unformed diarrhea) stools. Using these methods, hNoV GI and GII persistence was investigated during free chlorination of municipal WW. A suite five of kinetic inactivation models was fit to viral reverse transcription-qPCR reduction data, and model predicted CT values for 1, 2, and 3 log 10 reduction of hNoV GI in municipal WW by free chlorine were 0.3, 2.1, and 7.8 mg-min/L, respectively. Model predicted CT values for reduction of hNoV GII in WW were 0.4, 2.0, and 7.0 mg-min/L, respectively. These results indicate that current WW treatment plant disinfection practices employing free chlorine are likely protective for public health with regards to noroviruses, and will achieve at least 3-log reduction of hNoV GI and GII RNA despite previous reports of high hNoV resistance. [ABSTRACT FROM AUTHOR]

Human noroviruses (hNoVs) are a known public health concern associated with the consumption of leafy green vegetables. While a number of studies have investigated pathogen reduction on the surfaces of leafy greens during the postharvest washing process, there remains a paucity of data on the level of treatment needed to inactivate viruses in the wash water, which is critical for preventing cross-contamination. The objective of this study was to quantify the susceptibility of hNoV genotype I (GI), hNoV GII, murine norovirus (MNV), and bacteriophage MS2 to free chlorine in whole leaf, chopped romaine, and shredded iceberg lettuce industrial leafy green wash waters, each sampled three times over a 4-month period. A suite of kinetic inactivation models was fit to the viral reduction data to aid in quantification of concentration-time (CT) values. Results indicate that 3-log10 infectivity reduction was achieved at CT values of less than 0.2 mg · min/liter for MNV and 2.5 mg · min/liter for MS2 in all wash water types. CT values for 2-log10 molecular reduction of hNoV GI in whole leaf and chopped romaine wash waters were 1.5 and 0.9 mg · min/liter, respectively. For hNoV GII, CT values were 13.0 and 7.5 mg · min/liter, respectively. In shredded iceberg wash water, 3-log10 molecular reduction was not observed for any virus over the time course of experiments. These findings demonstrate that noroviruses may exhibit genogroup-dependent resistance to free chlorine and emphasize the importance of distinguishing between genogroups in hNoV persistence studies. IMPORTANCE Postharvest washing of millions of pounds of leafy greens is performed daily in industrial processing facilities with the intention of removing dirt, debris, and pathogenic microorganisms prior to packaging. Modest inactivation of pathogenic microorganisms (less than 2 log10) is known to occur on the surfaces of leafy greens during washing. Therefore, the primary purpose of the sanitizing agent is to maintain microbial quality of postharvest processing water in order to limit cross-contamination. This study modeled viral inactivation data and quantified the free-chlorine CT values that processing facilities must meet in order to achieve the desired level of hNoV GI and GII reduction. Disinfection experiments were conducted in industrial leafy green wash water collected from a full-scale fresh produce processing facility in the United States, and hNoV GI and GII results were compared with surrogate molecular and infectivity data. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus naturally occurs in brackish and marine waters and is one of the leading causes of seafood-borne illness. Previous work studying the ecology of V. parahaemolyticus has often been limited in geographic extent and lacked a full range of environmental measures. This study used a unique large data set of surface water samples in the Chesapeake Bay (n = 1,385) collected from 148 monitoring stations from 2007 to 2010. Water was analyzed for more than 20 environmental parameters, with additional meteorological and surrounding land use data. The V. parahaemolyticus-specific genetic markers thermolabile hemolysin (tlh), thermostable direct hemolysin (tdh), and tdh-related hemolysin (trh) were assayed using quantitative PCR (qPCR), and interval-censored regression models with nonlinear effects were estimated to account for limits of detection and quantitation. tlh was detected in 19.6% of water samples; tdh or trh markers were not detected. The results confirmed previously reported positive associations for V. parahaemolyticus abundance with temperature and turbidity and negative associations with high salinity (>10 to 23‰). Furthermore, the salinity relationship was determined to be a function of both low temperature and turbidity, with an increase of either nullifying the high salinity effect. Associations with dissolved oxygen and phosphate also appeared stronger when samples were taken near human developments. A renewed focus on the V. parahaemolyticus ecological paradigm is warranted to protect public health. IMPORTANCE Vibrio parahaemolyticus is one of the leading causes of seafood-borne illness in the United States and across the globe. Exposure is often through consuming raw or undercooked shellfish. Given the natural presence of the bacterium in the marine environment, an improved understanding of its environmental determinants is necessary for future preventative measures. This analysis of environmental Vibrio parahaemolyticus is one of only a few that utilize a large data set measured over a wide geographic and temporal range. The analysis also includes a large number of environmental parameters for Vibrio modeling, many of which have previously only been tested sporadically, and some of which have not been considered before. The results of the analysis revealed previously unknown relationships between salinity, turbidity, and temperature that provide significant insight into the abundance and persistence of V. parahaemolyticus bacterium in the environment. This information will be essential for developing environmental forecast models for the bacterium. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize human norovirus (hNoV) GI and GII reductions during disinfection by peracetic acid (PAA) and monochloramine in secondary wastewater (WW) and phosphate buffer (PB) as assessed by reverse transcription-qPCR (RT-qPCR). Infectivity and RT-qPCR reductions are also presented for surrogate viruses murine norovirus (MNV) and bacteriophage MS2 under identical experimental conditions to aid in interpretation of hNoV molecular data. In WW, RT-qPCR reductions were less than 0.5 log10 for all viruses at concentration-time (CT) values up to 450 mg-min/L except for hNoV GI, where 1 log10 reduction was observed at CT values of less than 50 mg-min/L for monochloramine and 200 mg-min/L for PAA. In PB, hNoV GI and MNV exhibited comparable resistance to PAA and monochloramine with CT values for 2 log10 RT-qPCR reduction between 300 and 360 mg-min/L. Less than 1 log10 reduction was observed for MS2 and hNoV GII in PB at CT values for both disinfectants up to 450 mg-min/L. Our results indicate that hNoVs exhibit genogroup dependent resistance and that disinfection practices targeting hNoV GII will result in equivalent or greater reductions for hNoV GI. These data provide valuable comparisons between hNoV and surrogate molecular signals that can begin the process of informing regulators and engineers on WW treatment plant design and operational practices necessary to inactivate hNoVs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Common breakthrough models were used to calculate fundamental treatment parameters. • PFAS breakthrough curves at different EBCTs evaluated for fundamental parameters. • Order-of-magnitude agreement was observed among all three fundamental parameters. • Fundamental parameters provided insight into solute properties. • Fundamental parameters also allow for models to be used in predictive application. Successful treatment of per- and polyfluoroalkyl substances (PFAS) contamination by adsorptive fixed bed media has been well established in literature and practice, but kinetic effects are important for these compounds. Common kinetic models of adsorption are descriptively fit to experimental data obtained from a particular design case, leading previous literature to dismiss these models as unable to provide useful information across changes to key operational variables. However, some descriptive models, such as the Clark and Bohart-Adams models, have mechanistic derivations with fundamental constants. The objective of this study was to evaluate the consistency of these fundamental constants across different experimental empty-bed contact times (EBCTs), and to evaluate the accuracy of using fundamental constants obtained at one EBCT to predict breakthrough at another EBCT. A total of 53 pilot-scale PFAS breakthrough curves through granular activated carbon (GAC) and ion exchange (IX) media were fitted to the Bohart-Adams and Clark models. Models were used to generate fundamental bed capacity, Freundlich, and kinetic constants. For each solute-media pair, the fundamental bed capacity and Freundlich constants had good agreement and low error across different EBCTs, while the kinetic constant had higher error with some EBCT dependance, but good order-of-magnitude agreement. The fundamental constants provided insights into the solute-media interaction, and predictive curves based on these fundamental constants provided reasonable estimates of breakthrough. The measurement of consistent values of underlying constants measured at different EBCT in this study suggests that the Clark and Bohart-Adams models can indeed be used to make predictions by varying parameters that are explicitly accounted for in the models, allowing for breakthrough curves generated at one EBCT to be used to predict breakthrough at another EBCT. [ABSTRACT FROM AUTHOR]

Water and sanitation indicators under the Millennium Development Goals failed to capture high-risk practices undertaken on a regular basis. In conjunction with local partners, fourteen rounds of household surveys using mobile phones with a customized open-source application were conducted across nine study geographies in Asia and Africa. In addition to the main water and sanitation facilities, interviewees (n = 245,054) identified all water and sanitation options regularly used for at least one season of the year. Unimproved water consumption and open defecation were targeted as high-risk practices. We defined underreporting as the difference between the regular and main use of high-risk practices. Our estimates of high-risk practices as the main option matched the widely accepted Demographic and Health Surveys (DHS) estimates within the 95% confidence interval. However, estimates of these practices as a regular option was far higher than the DHS estimates. Across the nine geographies, median underreporting of unimproved water use was 5.5%, with a range of 0.5% to 13.9%. Median underreporting of open defecation was much higher at 9.9%, with a range of 2.7% to 11.5%. This resulted in an underreported population of 25 million regularly consuming unimproved water and 50 million regularly practicing open defecation. Further examination of data from Ethiopia suggested that location and socio-economic factors were significant drivers of underreporting. Current global monitoring relies on a framework that considers the availability and use of a single option to meet drinking water and sanitation needs. Our analysis demonstrates the use of multiple options and widespread underreporting of high-risk practices. Policies based on current monitoring data, therefore, fail to consider the range of challenges and solutions to meeting water and sanitation needs, and result in an inflated sense of progress. Mobile surveys offer a cost-effective and innovative platform to rapidly and repeatedly monitor critical development metrics. [ABSTRACT FROM AUTHOR]

• Anion exchange generally outperformed granular activated carbon. • Correlation between chain-length and bed life within PFAS class. • Short service times for short and ultrashort-chain perfluorocarboxylic acids. • Competitive adsorption behavior on activated carbon shown with molar mass balance. • Systematic reduction in bed lives for branched versus linear isomers. Widespread contamination of groundwater with per- and polyfluoroalkyl substances (PFAS) has required drinking water producers to quickly adopt practical and efficacious treatments to limit human exposure and deleterious health outcomes. This pilot-scale study comparatively investigated PFAS adsorption behaviors in granular activated carbon (GAC) and two strong-base gel anion exchange resin (AER) columns operated in parallel over a 441-day period to treat contaminated groundwater dominated by short-chain perfluorocarboxylic acids (PFCA). Highly-resolved breakthrough profiles of homologous series of 2–8 CF 2 PFCA and perfluorosulfonic acids (PFSA), including ultrashort-chain compounds and branched isomers, were measured to elucidate adsorption trends. Sample ports at intermediate bed depths could predict 50% breakthrough of compounds on an accelerated basis, but lower empty bed contact times led to conservative estimates of initial breakthrough. Homologous PFAS series displayed linear (GAC) and log-linear (AER) relationships between chain-length and breakthrough, independent of initial concentration. AERs generally outperformed GAC on a normalized bed volume basis, and this advantage widened with increasing PFAS chain-length. As designed, all treatments would have short full-scale service times (≤142 days for GAC; ≤61 days for AERs) before initial breakthrough of short-chain (2–4 CF 2) PFCA. However, AER displayed far longer breakthrough times for PFSA compared to GAC (>3× treatment time), and breakthrough was not observed for PFSA with >4 CF 2 in AERs. GAC had a finite molar adsorption capacity for total PFAS, leading to a stoichiometric replacement of short-chain PFCA by PFSA and longer-chain PFCA over time. AERs quickly reached a finite adsorption capacity for PFCA, but they showed substantially greater selectivity for PFSA whose capacity was not reached within the duration of the pilot. Breakthrough characteristics of keto- and unsaturated-PFSA, identified in the groundwater by suspect screening, were also evaluated in absence of reference standards. Modified PFAS structures (branched, keto-, unsaturated-) broke through faster than linear and unmodified perfluorinated structures with equal degrees of fluorination, and the effects were more pronounced in GAC compared to AERs. The results highlight that the design of robust PFAS treatment systems should consider facets beyond current PFAS targets including operational complexities and impacts of unregulated and unmonitored co-contaminants. [Display omitted] [ABSTRACT FROM AUTHOR]

Over two billion people worldwide lack access to an improved sanitation facility that adequately retains or treats feces. This results in the potential for fecal material containing enteric pathogens to contaminate the environment, including household floors. This study aimed to assess how floor type and sanitation practices impacted the concentration of fecal contamination on household floors. We sampled 189 floor surfaces within 63 households in a peri-urban community in Iquitos, Peru. All samples were analyzed for colony forming units (CFUs) of E. coli, and households were evaluated for their water, sanitation, and hygiene characteristics. Results of multivariate linear regression indicated that households with improved sanitation and cement floors in the kitchen area had reduced fecal contamination to those with unimproved sanitation and dirt floors (Beta: -1.18 log10 E. coli CFU/900 cm²; 95% confidence interval [CI]: -1.77, -0.60). Households that did not versus did share their sanitation facility also had less contaminated kitchen floors (Beta: -0.65 log10 E. coli CFU/900 cm²; 95% CI: -1.15, -0.16). These findings suggest that the sanitation facilities of a home may impact the microbial load found on floors, contributing to the potential for household floors to serve as an indirect route of fecal pathogen transmission to children. [ABSTRACT FROM AUTHOR]

For the fresh-cut produce industry, a critical area of concern is potential pathogen cross-contamination during wash operations when wash water is reused and re-circulated in wash systems continuously imputed with fresh-cut produce. However, little research has focused on the chemical properties of wash water. Organic input from residual soil and vegetable material deteriorates water quality and creates increasing chlorine demand within this wash water. This study evaluated the origins of chlorine demand input and chlorine decay kinetics of fresh-cut produce wash water. Using a model system, vegetable juice released per kg of processed produce for shredded romaine lettuce, shredded iceberg lettuce, shredded carrot and baby spinach was 82.1 mL/kg, 94.5 mL/kg, 158 mL/kg, and 2.26 mL/kg, respectively. Batch water analysis revealed a rapid reaction between constituents in the wash water and chlorine where over a 90 min observation period, 50% of chlorine demand occurred within first 5 min, underscoring the challenge for any water treatment process to reduce chlorine demand once vegetables are deposited into washing systems. Moreover, the results also showed sustained chlorine demand over 90-min periods, indicating an accumulative effect on chlorine consumption with continuous organic input. Additionally, HPLC-SEC analysis showed that the constituents contributing to chlorine demand are predominantly dissolved small molecules (<3400 Da), which will challenge water reuse treatment approaches. This study provides quantitative information of chlorine demand origins and chlorine decay kinetics in wash water and provides baseline data critical for integrating water reuse in the fresh produce processing industry. [ABSTRACT FROM AUTHOR]

Ribavirin is a pharmaceutical antiviral used for the treatment of RNA virus infections including norovirus, hepatitis C virus, hepatitis E virus, Lassa virus, respiratory syncytial virus, and rhinovirus. Despite the drug's history and documented efficacy, the antiviral mechanism of Ribavirin remains unclear. Mechanisms proposed include depletion of the intracellular GTP pool, immunomodulatory effects, induction of error catastrophe, inhibition of viral polymerase activity, and/or inhibition of viral capping. In the present study, we leveraged deep sequencing data to demonstrate that Ribavirin increases murine norovirus (MNV-1) viral diversity. By serial passaging MNV-1 in RAW 264.7 cells for twenty generations in the presence of Ribavirin, we demonstrated statistically significant increases in both the number of unique haplotypes and the average pairwise difference (APD). Based on statistically significant differences in the probability of nucleotide mutations based on Roche 454 sequencing, we also demonstrated that single nucleotide substitutions are increased in the presence of Ribavirin. Finally, we demonstrated Ribavirin's impact on statistically significantly reducing the relative proportion of the dominant sequence within the quasispecies. [ABSTRACT FROM AUTHOR]

Access to water and sanitation are important determinants of behavioral responses to hygiene and sanitation interventions. We estimated cluster-specific water access and sanitation coverage to inform a constrained randomization technique in the SHINE trial. Technicians and engineers inspected all public access water sources to ascertain seasonality, function, and geospatial coordinates. Households and water sources were mapped using open-source geospatial software. The distance from each household to the nearest perennial, functional, protected water source was calculated, and for each cluster, the median distance and the proportion of households within <500 m and >1500 m of such a water source. Cluster-specific sanitation coverage was ascertained using a random sample of 13 households per cluster. These parameters were included as covariates in randomization to optimize balance in water and sanitation access across treatment arms at the start of the trial. The observed high variability between clusters in both parameters suggests that constraining on these factors was needed to reduce risk of bias. [ABSTRACT FROM AUTHOR]

Manure spills into streams are relatively frequent, but no studies have characterized stream contamination with zoonotic and veterinary pathogens, or fecal chemicals, following a spill. We tested stream water and sediment over 25 days and downstream for 7.6 km for the following: fecal indicator bacteria (FIB), the fecal indicator chemicals cholesterol and coprostanol, 20 genes for zoonotic and swine-specific bacterial pathogens by presence/absence PCR for viable cells, one swine-specific Escherichia coli toxin gene (STII gene) by quantitative PCR (qPCR), and nine human and animal viruses by qPCR or reverse transcription-qPCR. Twelve days postspill, and 4.2 km downstream, water concentrations of FIB, cholesterol, and coprostanol were 1 to 2 orders of magnitude greater than those detected before, or above, the spill, and genes indicating viable zoonotic or swine-infectious Escherichia coli were detected in water or sediment. STII gene levels increased from undetectable before or above the spill to 105 copies/ 100 ml of water 12 days postspill. Thirteen of 14 water (8/9 sediment) samples had viable STII-carrying cells postspill. Eighteen days postspill, porcine adenovirus and teschovirus were detected 5.6 km downstream. FIB concentrations (per gram [wet weight]) in sediment were greater than in water, and sediment was a continuous reservoir of genes and chemicals postspill. Constituent concentrations were much lower, and detections less frequent, in a runoff event (200 days postspill) following manure application, although the swine-associated STII and stx2e genes were detected. Manure spills are an underappreciated pathway for livestock-derived contaminants to enter streams, with persistent environmental outcomes and the potential for human and veterinary health consequences. [ABSTRACT FROM AUTHOR]

The increased awareness of the role of environmental matrices in enteric disease transmission has resulted in the need for rapid, field-based methods for fecal indicator bacteria and pathogen detection. Evidence of the specificity of β-glucuronidase-based assays for detection of Escherichia coli from environmental matrices relevant to enteric pathogen transmission in developing countries, such as hands, soils, and surfaces, is limited. In this study, we quantify the false-positive rate of a β-glucuronidasebased E. coli detection assay (Colilert) for two environmental reservoirs in Bangladeshi households (hands and soils) and three fecal composite sources (cattle, chicken, and humans). We investigate whether or not the isolation source of E. coli influences phenotypic and genotypic characteristics. Phenotypic characteristics include results of biochemical assays provided by the API- 20E test; genotypic characteristics include the Clermont phylogroup and the presence of enteric and/or environmental indicator genes sfmH, rfaI, and fucK. Our findings demonstrate no statistically significant difference in the false-positive rate of Colilert for environmental compared to enteric samples. E. coli isolates from all source types are genetically diverse, representing six of the seven phylogroups, and there is no difference in relative frequency of phylogroups between enteric and environmental samples. We conclude that Colilert, and likely other β-glucuronidase-based assays, is appropriate for detection of E. coli on hands and in soils with low false-positive rates. Furthermore, E. coli isolated from hands and soils in Bangladeshi households are diverse and indistinguishable from cattle, chicken, and human fecal isolates, using traditional biochemical assays and phylogrouping. [ABSTRACT FROM AUTHOR]

Recent studies showing an association between fecal indicator organisms (FIOs) in sand and gastrointestinal (GI) illness among beachgoers with sand contact have important public health implications because of the large numbers of people who recreate at beaches and engage in sand contact activities. Yet, factors that influence fecal pollution in beach sand remain unclear. During the 2007 National Epidemiological and Environmental Assessment of Recreational (NEEAR) Water Study, sand samples were collected at three locations (60 m apart) on weekend days (Sat, Sun) and holidays between June and September at two marine beaches — Fairhope Beach, AL and Goddard Beach, RI — with nearby publicly-owned treatment works (POTWs) outfalls. F + coliphage, enterococci, Bacteroidales , fecal Bacteroides spp., and Clostridium spp. were measured in sand using culture and qPCR-based calibrator-cell equivalent methods. Water samples were also collected on the same days, times and transects as the 144 sand samples and were assayed using the same FIO measurements. Weather and environmental data were collected at the time of sample collection. Mean FIO concentrations in sand varied over time, but not space. Enterococci CFU and CCE densities in sand were not correlated, although other FIOs in sand were. The strongest correlation between FIO density in sand and water was fecal Bacteroides CCE, followed by enterococci CFU, Clostridium spp. CCE, and Bacteroidales CCE. Overall, the factors associated with FIO concentrations in sand were related to the sand–water interface (i.e., sand-wetting) and included daily average densities of FIOs in water, rainfall, and wave height. Targeted monitoring that focuses on daily trends of sand FIO variability, combined with information about specific water quality, weather, and environmental factors may inform beach monitoring and management decisions to reduce microbial burdens in beach sand. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency. [ABSTRACT FROM AUTHOR]