@article{escudero-abarca_goulter_manuel_leslie_green_arbogast_jaykus_2022, title={Comparative Assessment of the Efficacy of Commercial Hand Sanitizers Against Human Norovirus Evaluated by an in vivo Fingerpad Method}, volume={13}, ISSN={["1664-302X"]}, DOI={10.3389/fmicb.2022.869087}, abstractNote={Human noroviruses (hNoV) are the leading cause of acute non-bacterial gastroenteritis worldwide and contaminated hands play a significant role in the spread of disease. Some hand sanitizers claim to interrupt hNoV transmission, but their antiviral efficacy on human hands is poorly characterized. The purpose of this work was to characterize the efficacy of representative commercial hand sanitizers against hNoV using an in vivo fingerpad method (ASTM E1838-17). Eight products [seven ethanol-based and one benzalkonium chloride (BAK)-based], and a benchmark 60% ethanol solution, were each evaluated on 10 human volunteers using the epidemic GII.4 hNoV strain. Virus titers before and after treatment were evaluated by RT-qPCR preceded by RNase treatment; product efficacy was characterized by log10 reduction (LR) in hNoV genome equivalent copies after treatment. The benchmark treatment produced a 1.7 ± 0.5 LR, compared with Product A (containing 85% ethanol) which produced a 3.3 ± 0.3 LR and was the most efficacious (p < 0.05). Product B (containing 70% ethanol), while less efficacious than Product A (p < 0.05), performed better than the benchmark with a LR of 2.4 ± 0.4. Five of the other ethanol-based products (labeled ethanol concentration ranges of 62–80%) showed similar efficacy to the 60% ethanol benchmark with LR ranging from 1.3 to 2.0 (p > 0.05). Product H (0.1% BAK) was less effective than the benchmark with a LR of 0.3 ± 0.2 (p < 0.05). None of the products screened were able to completely eliminate hNoV (maximum assay resolution 5.0 LR). Product performance was variable and appears driven by overall formulation. There remains a need for more hand sanitizer formulations having greater activity against hNoV, a virus that is comparatively recalcitrant relative to other pathogens of concern in community, healthcare, and food preparation environments.}, journal={FRONTIERS IN MICROBIOLOGY}, author={Escudero-Abarca, Blanca I. and Goulter, Rebecca M. and Manuel, Clyde S. and Leslie, Rachel A. and Green, Kristen and Arbogast, James W. and Jaykus, Lee-Ann}, year={2022}, month={Apr} }
 @article{escudero-abarca_goulter_bradshaw_faircloth_leslie_manuel_arbogast_jaykus_2022, title={Efficacy of an alcohol-based surface disinfectant formulation against human norovirus}, ISSN={["1365-2672"]}, DOI={10.1111/jam.15479}, abstractNote={Abstract}, journal={JOURNAL OF APPLIED MICROBIOLOGY}, author={Escudero-Abarca, Blanca I and Goulter, Rebecca M. and Bradshaw, Justin and Faircloth, Jeremy and Leslie, Rachel A. and Manuel, Clyde S. and Arbogast, James W. and Jaykus, Lee-Ann}, year={2022}, month={Feb} }
 @article{faircloth_goulter_manuel_arbogast_escudero-abarca_jaykus_2022, title={The Efficacy of Commercial Surface Sanitizers against Norovirus on Formica Surfaces with and without Inclusion of a Wiping Step}, ISSN={["1098-5336"]}, DOI={10.1128/aem.00807-22}, abstractNote={Human noroviruses (hNoVs) are the leading cause of acute gastroenteritis and food-borne disease worldwide. Noroviruses are difficult to inactivate, being recalcitrant to sanitizers and disinfectants commonly used by the retail food sector.}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Faircloth, Jeremy and Goulter, Rebecca M. and Manuel, Clyde S. and Arbogast, James W. and Escudero-Abarca, Blanca and Jaykus, Lee-Ann}, year={2022}, month={Aug} }
 @article{wilson_reynolds_jaykus_escudero-abarca_gerba_2020, title={Comparison of estimated norovirus infection risk reductions for a single fomite contact scenario with residual and nonresidual hand sanitizers}, volume={48}, ISSN={["1527-3296"]}, DOI={10.1016/j.ajic.2019.09.010}, abstractNote={•The residual hand sanitizer out-performed the nonresidual hand sanitizer. •Residual hand sanitizer may reduce infection risk for up to 4 hours. •Longer hand sanitizer contact time translated to higher risk reductions. Background The purpose of this study was to relate experimentally measured log10 human norovirus reductions for a nonresidual (60% ethanol) and a residual (quaternary ammonium-based) hand sanitizer to infection risk reductions. Methods Human norovirus log10 reductions on hands for both sanitizers were experimentally measured using the ASTM International Standard E1838-10 method, with modification. Scenarios included product application to: (1) inoculated fingerpads with 30- and 60-second contact times, and (2) hands followed by inoculation with human norovirus immediately and 4 hours later. Hand sanitizer efficacies were used in a mathematical model estimating norovirus infection risk from a single hand-to-fomite contact under low and high environmental contamination conditions. Results The largest log10 reductions for the residual and nonresidual hand sanitizers were for a 60-second contact time, reducing infection risk by approximately 99% and 85%, respectively. Four hours after application, the residual hand sanitizer reduced infection risks by 78.5% under high contamination conditions, whereas the nonresidual hand sanitizer offered no reduction. Discussion Log10 virus and infection risk reductions were consistently greater for the residual hand sanitizer under all scenarios. Further data describing residual hand sanitizer efficacy with additional contamination or tactile events are needed. Conclusions Residual antinoroviral hand sanitizers may reduce infection risks for up to 4 hours. The purpose of this study was to relate experimentally measured log10 human norovirus reductions for a nonresidual (60% ethanol) and a residual (quaternary ammonium-based) hand sanitizer to infection risk reductions. Human norovirus log10 reductions on hands for both sanitizers were experimentally measured using the ASTM International Standard E1838-10 method, with modification. Scenarios included product application to: (1) inoculated fingerpads with 30- and 60-second contact times, and (2) hands followed by inoculation with human norovirus immediately and 4 hours later. Hand sanitizer efficacies were used in a mathematical model estimating norovirus infection risk from a single hand-to-fomite contact under low and high environmental contamination conditions. The largest log10 reductions for the residual and nonresidual hand sanitizers were for a 60-second contact time, reducing infection risk by approximately 99% and 85%, respectively. Four hours after application, the residual hand sanitizer reduced infection risks by 78.5% under high contamination conditions, whereas the nonresidual hand sanitizer offered no reduction. Log10 virus and infection risk reductions were consistently greater for the residual hand sanitizer under all scenarios. Further data describing residual hand sanitizer efficacy with additional contamination or tactile events are needed. Residual antinoroviral hand sanitizers may reduce infection risks for up to 4 hours.}, number={5}, journal={AMERICAN JOURNAL OF INFECTION CONTROL}, author={Wilson, Amanda M. and Reynolds, Kelly A. and Jaykus, Lee-Ann and Escudero-Abarca, Blanca and Gerba, Charles P.}, year={2020}, month={May}, pages={538–544} }
 @article{escudero-abarca_goulter_arbogast_leslie_green_jaykus_2020, title={Efficacy of alcohol-based hand sanitizers against human norovirus using RNase-RT-qPCR with validation by human intestinal enteroid replication}, volume={71}, ISSN={["1472-765X"]}, DOI={10.1111/lam.13393}, abstractNote={Successful human norovirus (HuNoV) cultivation in stem cell‐derived human intestinal enteroids (HIE) was recently reported. The purpose of this study was to evaluate the anti‐HuNoV efficacy of two alcohol‐based commercial hand sanitizers and 60% ethanol by suspension assay using RNase‐RT‐qPCR, with subsequent validation of efficacy by HuNoV cultivation using the HIE model. In suspension, when evaluated by RNase‐RT‐qPCR, 60% ethanol resulted in less than one log10 reduction in HuNoV genome equivalent copies (GEC) regardless of contact time (30 or 60s) or soil load. The two commercial products outperformed 60% ethanol regardless of contact time or soil load, providing 2·2–3·2 log10 HuNoV GEC reductions by suspension assay. Product B could not be validated in the HIE model due to cytotoxicity. Following a 60s exposure, viral replication in the HIE model increased 1·9 ± 0·2 log10 HuNoV GEC for the neutralization (positive) control and increased 0·9 ± 0·2 log10 HuNoV GEC in challenged HIE after treatment with 60% ethanol. No HuNoV replication in HIE was observed after a 60 s exposure to Product A.}, number={6}, journal={LETTERS IN APPLIED MICROBIOLOGY}, author={Escudero-Abarca, B. I. and Goulter, R. M. and Arbogast, J. W. and Leslie, R. A. and Green, K. and Jaykus, L. -A.}, year={2020}, month={Dec}, pages={605–610} }
 @article{suh_choi_dwivedi_moore_escudero-abarca_jaykus_2018, title={Use of DNA aptamer for sandwich type detection of Listeria monocytogenes}, volume={557}, DOI={10.1016/j.ab.2018.04.009}, abstractNote={A single stranded (ss) DNA aptamer, specific to members of Listeria genus, was used to develop a two-site binding sandwich assay for capture and detection of L. monocytogenes. Antibody-immobilized immunomagnetic beads were used to capture L. monocytogenes, followed by their exposure to the aptamer detector. Detection was achieved by amplification of cell-bound aptamers by qPCR. The lower limit of detection for the combined assay was 2.5 CFU L. monocytogenes in 500 μl buffer. This is juxtaposed to a detection limit of 2.4 log10 CFU in 500 μl buffer for immunomagnetic separation coupled with qPCR detection of L. monocytogenes targeting the hly gene. When applied to turkey deli meat, subjected to 24 h of non-selective enrichment, the two-site binding sandwich assay showed positive results at initial inoculum levels of 1–2 log10 CFU per 25 g sample. Because of its lower limit of detection, the assay reported here could be useful for detection of L. monocytogenes in foods and environmental samples.}, journal={ANALYTICAL BIOCHEMISTRY}, author={Suh, Soo Hwan and Choi, Soo Jung and Dwivedi, Hari P. and Moore, Matthew D. and Escudero-Abarca, Blanca I and Jaykus, Lee-Ann}, year={2018}, pages={27–33} }
 @article{tung-thompson_escudero-abarca_outlaw_ganee_cassard_mabilat_jaykus_2017, title={Evaluation of a Surface Sampling Method for Recovery of Human Noroviruses Prior to Detection Using Reverse Transcription Quantitative PCR}, volume={80}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028x.jfp-16-276}, abstractNote={Human noroviruses are the most common cause of acute viral gastroenteritis, and the environmental persistence of these viruses contributes to their transmissibility. Environmental sampling is thus an important tool for investigating norovirus outbreaks and for assessing the effectiveness of cleaning and decontamination regimens. The purpose of this study was to evaluate a sampling material (wipes) for their efficacy at recovering human norovirus from hard surfaces and foods. Dilutions of a human norovirus GII.4 stool specimen derived from an outbreak were applied to hard surfaces (stainless steel and ceramic) and the surfaces of representative foods (green pepper, apple, tomato, and cheese). The viruses were recovered at various times postinoculation using the wipes, followed by RNA extraction and reverse transcription quantitative PCR. Recovery efficiency ranged from 74% to almost 100% for all artificially inoculated hard surfaces and for most fresh produce surfaces. Less efficient recovery was observed for cheese. Viral RNA could be recovered from select surfaces for up to 7 days postinoculation, with a <1 log reduction in genome copy number. In field tests, 24 (11%) of 210 environmental samples collected during winter 2012 from restrooms in North Carolina were presumptively positive for human norovirus, and six of these samples were confirmed as GII.4 by sequencing. These wipes may be a valuable tool for investigations of norovirus outbreaks and studies of norovirus prevalence.}, number={2}, journal={JOURNAL OF FOOD PROTECTION}, author={Tung-Thompson, Grace and Escudero-Abarca, Blanca I. and Outlaw, Janie and Ganee, Arnaud and Cassard, Sylvanie and Mabilat, Claude and Jaykus, Lee-Ann}, year={2017}, month={Feb}, pages={231–236} }
 @article{moore_escudero-abarca_suh_jaykus_2015, title={Generation and characterization of nucleic acid aptamers targeting the capsid P domain of a human norovirus GII.4 strain}, volume={209}, ISSN={["1873-4863"]}, DOI={10.1016/j.jbiotec.2015.06.389}, abstractNote={Human noroviruses (NoV) are the leading cause of acute viral gastroenteritis worldwide. Significant antigenic diversity of NoV strains has limited the availability of broadly reactive ligands for design of detection assays. The purpose of this work was to produce and characterize single stranded (ss)DNA aptamers with binding specificity to human NoV using an easily produced NoV target—the P domain protein. Aptamer selection was done using SELEX (Systematic Evolution of Ligands by EXponential enrichment) directed against an Escherichia coli-expressed and purified epidemic NoV GII.4 strain P domain. Two of six unique aptamers (designated M1 and M6-2) were chosen for characterization. Inclusivity testing using an enzyme-linked aptamer sorbent assay (ELASA) against a panel of 14 virus-like particles (VLPs) showed these aptamers had broad reactivity and exhibited strong binding to GI.7, GII.2, two GII.4 strains, and GII.7 VLPs. Aptamer M6-2 exhibited at least low to moderate binding to all VLPs tested. Aptamers significantly (p < 0.05) bound virus in partially purified GII.4 New Orleans outbreak stool specimens as demonstrated by ELASA and aptamer magnetic capture (AMC) followed by RT-qPCR. This is the first demonstration of human NoV P domain protein as a functional target for the selection of nucleic acid aptamers that specifically bind and broadly recognize diverse human NoV strains.}, journal={JOURNAL OF BIOTECHNOLOGY}, author={Moore, Matthew D. and Escudero-Abarca, Blanca I. and Suh, Soo Hwan and Jaykus, Lee-Ann}, year={2015}, month={Sep}, pages={41–49} }
 @article{escudero-abarca_rawsthorne_goulter_suh_jaykus_2014, title={Molecular methods used to estimate thermal inactivation of a prototype human norovirus: More heat resistant than previously believed?}, volume={41}, ISSN={["1095-9998"]}, DOI={10.1016/j.fm.2014.01.009}, abstractNote={Two molecular-based methods for estimating capsid integrity as a proxy for virus infectivity were used to produce thermal inactivation profiles of Snow Mountain virus (SMV), a prototype human norovirus (HuNoV). Monodispersed virus suspensions were exposed to 77, 80, 82 and 85 °C for various times, pre-treated with either propidium monoazide (PMA) or RNase, and subjected to RNA isolation followed by RT-qPCR amplification. D-values were 25.6 ± 2.8, 3.1 ± 0.1, 0.7 ± 0.04 and 0.2 ± 0.07 min at 77, 80, 82 and 85 °C, respectively for PMA-treated SMV; and 16.4 ± 0.4, 3.9 ± 0.2 0.9 ± 0.3 and 0.12 ± 0.00 min at 77, 80, 82 and 85 °C, respectively for RNase-treated SMV. Corresponding zD values were 3.80 °C and 3.71 °C for PMA and RNase-treated virus, respectively. Electron microscopy data applied to heat-treated virus-like particles supported this relatively high degree of thermal resistance. The data suggest that SMV is more heat resistant than common cultivable HuNoV surrogates. Standardized thermal inactivation methods (such as milk pasteurization) may not be stringent enough to eliminate this virus and perhaps other HuNoV.}, journal={FOOD MICROBIOLOGY}, author={Escudero-Abarca, B. I. and Rawsthorne, H. and Goulter, R. M. and Suh, S. H. and Jaykus, L. A.}, year={2014}, month={Aug}, pages={91–95} }
 @article{escudero-abarca_suh_moore_dwivedi_jaykus_2014, title={Selection, Characterization and Application of Nucleic Acid Aptamers for the Capture and Detection of Human Norovirus Strains}, volume={9}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0106805}, abstractNote={Human noroviruses (HuNoV) are the leading cause of acute viral gastroenteritis and an important cause of foodborne disease. Despite their public health significance, routine detection of HuNoV in community settings, or food and environmental samples, is limited, and there is a need to develop alternative HuNoV diagnostic reagents to complement existing ones. The purpose of this study was to select and characterize single-stranded (ss)DNA aptamers with binding affinity to HuNoV. The utility of these aptamers was demonstrated in their use for capture and detection of HuNoV in outbreak-derived fecal samples and a representative food matrix. SELEX (Systematic Evolution of Ligands by EXponential enrichment) was used to isolate ssDNA aptamer sequences with broad reactivity to the prototype GII.2 HuNoV strain, Snow Mountain Virus (SMV). Four aptamer candidates (designated 19, 21, 25 and 26) were identified and screened for binding affinity to 14 different virus-like particles (VLPs) corresponding to various GI and GII HuNoV strains using an Enzyme-Linked Aptamer Sorbant Assay (ELASA). Collectively, aptamers 21 and 25 showed affinity to 13 of the 14 VLPs tested, with strongest binding to GII.2 (SMV) and GII.4 VLPs. Aptamer 25 was chosen for further study. Its binding affinity to SMV-VLPs was equivalent to that of a commercial antibody within a range of 1 to 5 µg/ml. Aptamer 25 also showed binding to representative HuNoV strains present in stool specimens obtained from naturally infected individuals. Lastly, an aptamer magnetic capture (AMC) method using aptamer 25 coupled with RT-qPCR was developed for recovery and detection of HuNoV in artificially contaminated lettuce. The capture efficiency of the AMC was 2.5–36% with an assay detection limit of 10 RNA copies per lettuce sample. These ssDNA aptamer candidates show promise as broadly reactive reagents for use in HuNoV capture and detection assays in various sample types.}, number={9}, journal={PLOS ONE}, author={Escudero-Abarca, Blanca I. and Suh, Soo Hwan and Moore, Matthew D. and Dwivedi, Hari P. and Jaykus, Lee-Ann}, year={2014}, month={Sep} }
 @article{liu_escudero_jaykus_montes_goulter_lichtenstein_fernandez_lee_de nardo_kirby_et al._2013, title={Laboratory Evidence of Norwalk Virus Contamination on the Hands of Infected Individuals}, volume={79}, ISSN={["1098-5336"]}, DOI={10.1128/aem.02576-13}, abstractNote={ABSTRACT}, number={24}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Liu, Pengbo and Escudero, Blanca and Jaykus, Lee-Ann and Montes, Julia and Goulter, Rebecca M. and Lichtenstein, Meredith and Fernandez, Marina and Lee, Joong-Chul and De Nardo, Elizabeth and Kirby, Amy and et al.}, year={2013}, month={Dec}, pages={7875–7881} }
 @article{escudero_rawsthorne_gensel_jaykus_2012, title={Persistence and Transferability of Noroviruses on and between Common Surfaces and Foods}, volume={75}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028x.jfp-11-460}, abstractNote={Human noroviruses (HuNoV) are the leading cause of foodborne disease, and poor personal hygiene practices of infected workers are the most common mode of contamination. The purpose of this study was to characterize the persistence and transferability of representative noroviruses Norwalk virus (NV), Snow Mountain virus (SMV), and murine norovirus 1 (MNV-1) on and between solid surfaces and foods. Changes in virus concentration on artificially inoculated solid surfaces (stainless steel, ceramic, and Formica) or lettuce were monitored over a period of 14 to 42 days. Virus transfer was evaluated from donor (solid surface) to recipient (food, e.g., lettuce and sliced turkey deli meat) for up to 2 h postinoculation. Viruses were recovered by elution and titered with reverse transcription quantitative PCR (RT-qPCR) and/or infectivity assay, as appropriate. Based on RTqPCR, the concentration of NV and SMV on surfaces dropped gradually over time, with an average reduction of 1.5 to 2.0 and 1.8 to 2.3 log, respectively, after 42 days, with no statistically significant differences by surface. When inoculated onto lettuce stored for 2 weeks at 4°C and room temperature, the titers of NV and SMV dropped by approximately 1.0 and 1.2 to 1.8 log, respectively. Comparatively, the RT-qPCR signal associated with purified HuNoV RNA placed on the same surfaces was more rapidly lost to degradation. Transfer efficiency ranged from 0 to 26 % for lettuce and from 55 to 95 % for sliced turkey deli meat, with statistically significant differences (P ≤ 0.05) in transferability as a function of contact pressure (100 and 1,000 g/9 cm(2)) and inoculum drying time. When similar experiments were done with MNV-1, infectious virus failed to be detected on solid surfaces after storage day 21, although the virus did persist on lettuce. This study provides much needed quantitative data for use in risk assessment efforts intended to characterize the transmission of HuNoV during food preparation and handling.}, number={5}, journal={JOURNAL OF FOOD PROTECTION}, author={Escudero, B. I. and Rawsthorne, H. and Gensel, C. and Jaykus, L. A.}, year={2012}, month={May}, pages={927–935} }