Moorman Eric, Montazeri Naim, Jaykus Lee-Ann
Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, North Carolina, USA.
Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, North Carolina, USA
Appl Environ Microbiol. 2017 Aug 1;83(16). doi: 10.1128/AEM.00653-17. Print 2017 Aug 15.
Human norovirus (NoV) is the leading cause of acute gastroenteritis worldwide. Persistence on surfaces and resistance to many conventional disinfectants contribute to widespread transmission of norovirus. We examined the efficacy of neutral electrolyzed water (NEW; pH 7) for inactivation of human NoV GII.4 Sydney in suspension (ASTM method 1052-11) and on stainless steel surfaces (ASTM method 1053-11) with and without an additional soil load. The impact of the disinfectant on viral capsid was assessed using reverse transcriptase quantitative PCR (RT-qPCR; with an RNase pretreatment), SDS-PAGE, transmission electron microscopy, and a histo-blood group antigen (HBGA) receptor-binding assay. These studies were done in parallel with those using Tulane virus (TuV), a cultivable human NoV surrogate. Neutral electrolyzed water at 250 ppm free available chlorine produced a 4.8- and 0.4-log reduction in NoV genome copy number after 1 min in suspension and on stainless steel, respectively. Increasing the contact time on surfaces to 5, 10, 15, and 30 min reduced human NoV genomic copies by 0.5, 1.6, 2.4, and 5.0 log and TuV infectious titers by 2.4, 3.0, 3.8, and 4.1 log PFU, respectively. Increased soil load effectively eliminated antiviral efficacy regardless of testing method and virus. Exposure to NEW induced a near complete loss of receptor binding (5 ppm, 30 s), degradation of VP1 major capsid protein (250 ppm, 5 min), and increased virus particle aggregation (150 ppm, 30 min). Neutral electrolyzed water at 250 ppm shows promise as an antinoroviral disinfectant when used on precleaned stainless steel surfaces. Norovirus is the leading cause of acute viral gastroenteritis worldwide. Transmission occurs by fecal-oral or vomitus-oral routes. The persistence of norovirus on contaminated environmental surfaces exacerbates its spread, as does its resistance to many conventional disinfectants. The purpose of this research was to evaluate the antinoroviral efficacy of neutral electrolyzed water (NEW), a novel chlorine-based disinfectant that can be used at reduced concentrations, making it more environmentally friendly and less corrosive than bleach. An industrial-scale electrochemical activation device capable of producing relatively stable electrolyzed water at a wide pH range was used in this study. Experiments showed that 250 ppm NEW effectively eliminated (defined as a 5-log reduction) human norovirus GII.4 Sydney (epidemic strain) on clean stainless steel surfaces after a 30-min exposure. Supporting studies showed that, like bleach, NEW causes inactivation by disrupting the virus capsid. This product shows promise as a bleach alternative with antinoroviral efficacy.
人诺如病毒（NoV）是全球急性胃肠炎的主要病因。它在物体表面的持久性以及对许多传统消毒剂的抗性导致了诺如病毒的广泛传播。我们研究了中性电解水（NEW；pH 7）在有或无额外污垢负载的情况下，对悬浮液中（ASTM方法1052 - 11）和不锈钢表面（ASTM方法1053 - 11）的人NoV GII.4悉尼株的灭活效果。使用逆转录定量PCR（RT - qPCR；经过核糖核酸酶预处理）、SDS - 聚丙烯酰胺凝胶电泳、透射电子显微镜和组织血型抗原（HBGA）受体结合试验评估了消毒剂对病毒衣壳的影响。这些研究与使用可培养的人NoV替代物图兰病毒（TuV）的研究并行进行。250 ppm游离有效氯的中性电解水在悬浮液中处理1分钟后，以及在不锈钢表面处理1分钟后，分别使NoV基因组拷贝数减少了4.8和0.4个对数级。将在表面的接触时间增加到5、10、15和30分钟，分别使人类NoV基因组拷贝数减少0.5、1.6、2.4和5.0个对数级，使TuV感染滴度分别降低2.4、3.0、3.8和4.1个对数级空斑形成单位。无论测试方法和病毒如何，污垢负载增加都有效消除了抗病毒效果。暴露于NEW会导致受体结合几乎完全丧失（5 ppm，30秒）、主要衣壳蛋白VP1降解（250 ppm，5分钟）以及病毒颗粒聚集增加（150 ppm，30分钟）。当用于预先清洁的不锈钢表面时，250 ppm的中性电解水有望成为一种抗诺如病毒消毒剂。诺如病毒是全球急性病毒性胃肠炎的主要病因。通过粪 - 口或呕吐物 - 口途径传播。诺如病毒在受污染的环境表面的持久性加剧了其传播，其对许多传统消毒剂的抗性也是如此。本研究的目的是评估中性电解水（NEW）的抗诺如病毒效果，NEW是一种新型的氯基消毒剂，可在较低浓度下使用，使其比漂白剂更环保且腐蚀性更小。本研究使用了一种能够在较宽pH范围内产生相对稳定电解水的工业规模电化学活化装置。实验表明，250 ppm的NEW在暴露30分钟后能有效消除（定义为减少5个对数级）清洁不锈钢表面上的人诺如病毒GII.4悉尼株（流行株）。支持性研究表明，与漂白剂一样，NEW通过破坏病毒衣壳导致病毒失活。该产品有望成为具有抗诺如病毒效果的漂白剂替代品。
