Disinfection is an essential measure for interrupting human norovirus (HuNoV) transmission, but it is difficult to evaluate the efficacy of disinfectants due to the absence of a practicable cell culture system for these viruses. The purpose of this study was to screen sodium hypochlorite and ethanol for efficacy against Norwalk virus (NV) and expand the studies to evaluate the efficacy of antibacterial liquid soap and alcohol-based hand sanitizer for the inactivation of NV on human finger pads. Samples were tested by real-time reverse transcription-quantitative PCR (RT-qPCR) both with and without a prior RNase treatment. In suspension assay, sodium hypochlorite concentrations of >160 ppm effectively eliminated RT-qPCR detection signal, while ethanol, regardless of concentration, was relatively ineffective, giving at most a 0.5 log 10 reduction in genomic copies of NV cDNA. Using the American Society for Testing and Materials (ASTM) standard finger pad method and a modification thereof (with rubbing), we observed the greatest reduction in genomic copies of NV cDNA with the antibacterial liquid soap treatment (0.67 to 1.20 log 10 reduction) and water rinse only (0.58 to 1.58 log 10 reduction). The alcohol-based hand sanitizer was relatively ineffective, reducing the genomic copies of NV cDNA by only 0.14 to 0.34 log 10 compared to baseline. Although the concentrations of genomic copies of NV cDNA were consistently lower on finger pad eluates pretreated with RNase compared to those without prior RNase treatment, these differences were not statistically significant. Despite the promise of alcohol-based sanitizers for the control of pathogen transmission, they may be relatively ineffective against the HuNoV, reinforcing the need to develop and evaluate new products against this important group of viruses.Human noroviruses (HuNoV) are the leading cause of acute nonbacterial gastroenteritis (11, 21). The U.S. Centers for Disease Control and Prevention estimate that approximately 23 million people suffer from HuNoV gastroenteritis each year. Indeed, 81% of outbreaks of nonbacterial gastroenteritis are caused by this agent (7,8). These viruses may contaminate food, water, hands, and inanimate surfaces and are readily transmitted by contact with contaminated objects, by consumption of fecally contaminated food or water, or between people. In particular, hands are thought to be a principal vehicle for HuNoV transmission. Although many different hand hygiene agents are available, these generally do not have specific virucidal claims against the HuNoV. Two widely used types of hand hygiene products are antibacterial liquid soaps and alcohol-based hand sanitizers.Little is known about the effectiveness of hand hygiene agents in reducing HuNoV on contaminated hands. One reason for this is that the HuNoV cannot be routinely cultured in vitro, a factor that complicates evaluation of the efficacy of disinfection strategies. As an alternative, investigators have used cultivable surrogates such as feline calicivirus (FCV) and murin...

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Understanding the fate of enteric viruses in water is vital for protection of water quality. However, the decay of enteric viruses is not well characterized, and its uncertainty has not been examined yet. In this study, the decay of coliphages, an indicator for enteric viruses, was investigated in situ under both sunlit and shaded conditions as well as in summer and winter. The decay rates of coliphages and their uncertainties were analyzed using a Bayesian approach. The results from the summer experiments revealed that the decay rates of somatic coliphages were significantly higher in sunlight (1.29 ± 0.06 day) than in shade (0.96 ± 0.04 day), but the decay rates of male-specific (F+) coliphages were not significantly different between sunlight (1.09 ± 0.09 day) and shaded treatments (1.11 ± 0.08 day). The decay rates of both F+ coliphages (0.25 ± 0.02 day) and somatic coliphages (0.12 ± 0.01 day) in winter were considerably lower than those in summer. Temperature and chlorophyll a (chla) concentration varied significantly (p < 0.001) between the two seasons, suggesting that these parameters might be important contributors to the seasonal variation of coliphage decay. Additionally, the Bayesian approach provided full distributions of decay rates and reduced the uncertainty, offering useful information for comparing decay rates under different conditions.

A simple portable continuous L-lactate monitoring system combining elegant ultrafiltration sample collection and storage with a lactate biosensor has been developed. The sensor has a detection range from 0.05mM to 30mM 2153 Downloaded by [Temple University Libraries] at 20:54 13 June 2016 2154 CHENG ETAL. lactate dependent on different assignments of the PCS hydrogel complex layer. The sensor shows excellent performance on sensitivity and validity as well as operational stability over one month. Samples containing different concentrations of lactate were collected in six hours with an ultrafiltration probe and stored in a 6m long PEEK tube of 125jxm in internal diameter. The ultraslow flow rate of 100 to 350nl/min was controlled by adjusting the restriction in the portable plastic syringe pump and a constant flow can be maintained over 24 hours. The collected samples were then detected after reversing the flow with a lactate sensor. The total weight of the collection system is only 8g, allowing free movement of the person being tested.

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