Human noroviruses are the leading cause of viral gastroenteritis. In the absence of a practical culture technique for routine analysis of infectious noroviruses, several methods have been developed to discriminate between infectious and non-infectious viruses by removing non-viable viruses prior to analysis by RT-qPCR. In this study, two such methods (RNase and porcine gastric mucin) which were designed to remove viruses with compromised capsids (and therefore assumed to be non-viable), were assessed for their ability to quantify viable F-specific RNA bacteriophage (FRNAP) and human norovirus following inactivation by UV-C or heat. It was found that while both methods could remove a proportion of non-viable viruses, a large proportion of non-viable virus remained to be detected by RT-qPCR, leading to overestimations of the viable population. A model was then developed to determine the proportion of RT-qPCR detectable RNA from non-viable viruses that must be removed by such methods to reduce overestimation to acceptable levels. In most cases, nearly all non-viable virus must be removed to reduce the log overestimation of viability to within levels that might be considered acceptable (e.g. below 0.5 log₁₀). This model could be applied when developing alternative pre-treatment methods to determine how well they should perform to be comparable to established infectivity assays.

中文翻译：

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评估衣壳完整性检测在热或紫外线照射下灭活的感染性诺如病毒的适用性评估。

人诺如病毒是病毒性肠胃炎的主要原因。在缺乏用于感染性诺如病毒常规分析的实用培养技术的情况下，已开发出几种方法，通过在RT-qPCR分析之前去除无活力的病毒来区分感染性和非感染性病毒。在这项研究中，评估了两种这样的方法（RNA酶和猪胃粘蛋白），它们被设计用来去除衣壳受损的病毒（因此被认为是不可行的），以量化可行的F特异性RNA噬菌体（FRNAP）的能力。和人类诺如病毒后，通过UV-C或热灭活。已经发现，尽管两种方法都可以去除一定比例的不活病毒，但仍有大量的不活病毒需要通过RT-qPCR进行检测，这导致对活菌种群的高估。然后开发了一个模型，用于确定必须通过此类方法将不可存活病毒中RT-qPCR可检测RNA的比例，以将高估降低到可接受水平。在大多数情况下，几乎所有非活病毒都必须去除，以将对数生存能力的对数高估降低到可以接受的水平内（例如，低于0.5 log₁₀）。在开发替代的预处理方法时，可以使用此模型来确定其性能应与已建立的传染性测定法相媲美。