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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.

Background: Healthcare-associated norovirus outbreaks place a large burden on healthcare staff. Environmental service workers (ESWs), however, remain understudied despite high contact with potentially contaminated surfaces. Understanding the magnitude of the risk of norovirus infection in healthcare ESWs can protect workers and improve infection control.Aim: This study simulated the risk of norovirus infection for unprotected ESWs after a single fomite contact, assuming no disinfection or protective equipment, in norovirus-positive patient rooms. In addition, the risk of secondary surface transmission from norovirus-exposed ESWs was simulated.Methods: A quantitative microbial risk assessment employing two-dimensional Monte Carlo simulation with parameters extracted from the literature was used to estimate norovirus infection from multiple fomite contact scenarios defined by: norovirus source (patient vomit/diarrhoea), location (bathroom/patient room) and target outcome (ESW/secondary illness).Findings: Unprotected ESWs have a maximum estimated risk of norovirus infection of 33% (1:3) for a single fomite contact in a room where a norovirus-positive patient had a diarrhoeal event. Patient vomit events lead to fomite contact risk estimates that are four orders of magnitude lower than those for diarrhoeal events. The estimated risk of secondary illness from touching a common surface is as high as 25% (1:4) after single fomite exposure following a diarrhoeal event.Conclusions: A single fomite contact may lead to sizable risk of norovirus infection in ESWs if personal protective equipment and disinfection are not used appropriately. ESWs can also transfer virus to secondary surfaces, initiating further infections. Interventions are needed to reduce fomite transfer of norovirus, and protect patients and staff from nosocomial infections. [ABSTRACT FROM AUTHOR]

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.

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]