Search

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 point-of-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) = 13:2to7:0 [micro]g/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 [micro]g/g creatinine) and 30% in the Intensive arm (GM = 11:2 to 7:82 [micro]g/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. https://doi.org/10.1289/EHP12548, Introduction In the United States, >2 million individuals use private wells with arsenic levels above the US Environmental Protection Agency (EPA) guideline for drinking water ( Despite the growing evidence [...]

BackgroundNorovirus 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.MethodsA 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

Purpose of reviewThis review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transmission routes and the natural history and ecology of disease in different populations (including asymptomatic infection rates).Recent findingsWe review recent literature on the application of pathogen-specific antibody response data to estimate incidence and prevalence of acute infections and their utility to assess the contributions of waterborne transmission pathways. Advantages and technical challenges associated with the use of serum versus minimally invasive salivary antibody biomarkers in cross-sectional and prospective surveys are discussed. We highlight recent advances and challenges and outline future directions for research, development, and application of antibody-based and other immunological biomarkers of waterborne infections.

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-glucuronidase-based 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.

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., Author(s): Julie Hennegan 1,*, Alexandra K. Shannon 2, Jennifer Rubli 3, Kellogg J. Schwab 1, G. J. Melendez-Torres 4 Introduction Each day, more than 300 million women are menstruating [1]. [...]

The recovery efficiency of human waterborne pathogens and the bioaccumulation, depuration and inactivation rates of these pathogens by commercial market-size Crassostrea ariakensis triploids maintained in water of various salinity levels representing the salinity range of the Chesapeake Bay are determined. Aquacultures of nonnative oysters in the Chesapeake Bay have provided good ecological services in regard to efficient cleaning of human-infectious agents from the estuarine waters.

An immunoassay is described that can detect Norwalk virus and hepatitis A virus in stool samples and oysters. The Norwalk virus is the most common cause of non-bacterial gastroenteritis. The immunoassay can be automated and takes less time than some other methods.

A rapid and simple method for detecting Norwalk-like viruses and hepatitis A virus in food samples is presented. It uses HAV- or NLV-specific primers and reverse transcription PCR.

An immunoaffinity technique efficiently detects waterborne enteric viruses. The method involves indirect antibody capture of intact viruses and release of virion genomic RNA followed by reverse transcriptase PCR amplification and oligoprobe hybridization. The viruses are concentrated from huge volumes of water using 1MDS filters and washed with 1% beef extract-0.05 M glycine (BE/G). The BE/G eluate is concentrated and purified using polyethylene glycol (PEG) precipitation, ProCipitate precipitation, and then another PEG precipitation.

BACKGROUND: Use of engineered nanoparticles (NPs) in consumer products is resulting in NPs in drinking water sources. Subsequent NP breakthrough into treated drinking water is a potential exposure route and human health threat. OBJECTIVES: In this study we investigated the breakthrough of common NPs--silver (Ag), titanium dioxide (Ti[O.sub.2]), and zinc oxide (ZnO)--into finished drinking water following conventional and advanced treatment. METHODS: NPs were spiked into five experimental waters: groundwater, surface water, synthetic freshwater, synthetic freshwater containing natural organic matter, and tertiary wastewater effluent. Bench-scale coagulation/flocculation/sedimentation simulated conventional treatment, and microfiltration (MF) and ultrafiltration (UF) simulated advanced treatment. We monitored breakthrough of NPs into treated water by turbidity removal and inductively coupled plasma--mass spectrometry (ICP-MS). RESULTS: Conventional treatment resulted in 2-20%, 3-8%, and 48-99% of Ag, Ti[O.sub.2], and ZnO NPs, respectively, or their dissolved ions remaining in finished water. Breakthrough following MF was 1-45%> for Ag, 0^4% for Ti[O.sub.2], and 36-83% for ZnO. With UF, NP breakthrough was 0-2%, 0-4%, and 2-96% for Ag, Ti[O.sub.2], and ZnO, respectively. Variability was dependent on NP stability, with less breakthrough of aggregated NPs compared with stable NPs and dissolved NP ions. CONCLUSIONS: Although a majority of aggregated or stable NPs were removed by simulated conventional and advanced treatment, NP metals were detectable in finished water. As environmental NP concentrations increase, we need to consider NPs as emerging drinking water contaminants and determine appropriate drinking water treatment processes to fully remove NPs in order to reduce their potential harmful health outcomes., Introduction Engineered nanoparticles (NPs) are currently used in > 1,200 commercially available consumer products, including personal care products, food storage containers, cleaning supplies, bandages, clothing, and washing machines (Reijnders 2006). [...]

A study is conducted to evaluate the rates of bioaccumulation, retention, and depuration of viruses by Crassostrea virginica and C. ariakensis when the two oyster species are maintained in separate tanks containing synthetic seawater of various salinities at 8, 12, or 20 ppt. The findings have provided guidelines to assess the threat of C. ariakensis as a vehicle for viral pathogens due to the consumption of raw oysters and has validated the role for murine norovirus 1 (MNV-1) as a surrogate for human norovirus (NoV).

The applicability of selected enteric viral surrogates in predicting the persistence of human norovirus (NoV) seeded into surface water and groundwater used as source water for producing potable water is evaluated. Quantitative reverse transcription-PCR (qRT-PCR) assays are developed for each virus and the levels of infections virus and viral nucleic acid are monitored in spiked drinking source water over time.

A person with 30 minutes of occupational or nonoccupational exposure to urban feral pigeons is observed through the cleaning of surfaces contaminated with pigeon excrement. It is demonstrated that a person could inhale approximately 3.5 x [10.sup.3] Enterocytozoon bieneusi spores and a person nearby could inhale 1.3 x [10.sup.3] spores.

Susceptibilities to arsenite, arsenate, and the organoarsenical roxarsone are measured in 251 Campylobacter isolates from conventional and antimicrobial-free retail poultry products. Isolates from conventional poultry products have significantly higher roxarsone MICs (z= 8.22; P < 0.0001).

The detection of norovirus capsid protein is explored using three common mass spectrometry (MS)-based methods that are scanning of intact proteins, peptide mass fingerprinting, and peptide sequencing. This is the first report on MS-based detection of norovirus, accomplished by using structurally identical, noninfective virus-like particles at clinically relevant concentrations.

Research describes the development of a polymerase chain reaction (PCR) amplification and detection method for Toxoplasma gondii oocyst nucleic acids. The method uses uracil-N-glycosylase to prevent false-positives, an internal control to identify false-negatives, and an oligoprobe for the detection of nucleic acids using the PCR-enzyme immunoassay.