Gastroenteritis Section, Victorian Infectious Diseases Reference Laboratory, 10 Wreckyn Street, North Melbourne, Victoria 3051, Australia.
J Clin Microbiol. 2010 Mar;48(3):857-61. doi: 10.1128/JCM.01661-09. Epub 2010 Jan 20.
Noroviruses (NoVs) are now considered the most common cause of outbreaks of nonbacterial gastroenteritis, but the factors which control the incidence of NoVs are poorly understood. In 2006, the pattern of NoV outbreak epidemics in Victoria, Australia, changed compared to the pattern for 2002 to 2005 and 2007. This study examined molecular correlates of the changed NoV periodicity. For the period of 2002 to 2007, 8,507 fecal specimens from 1,495 gastroenteritis outbreaks were tested for NoV by reverse transcription-PCR, and 1,018 NoV outbreaks were identified. Nucleotide sequence analysis was used to define genotypes and GII.4 variants. For 2002 to 2007, GII.4 was the predominant genotype. For the period of 2002 to 2005 and 2007, a single NoV outbreak epidemic occurred in warmer months of each year, but in 2006 two epidemics occurred in 1 year, one in colder months and one in warmer months of the year. For 2002 to 2007, four major GII.4 variants, "2002 Oxford/Farmington Hills," "2004 Hunter," "2006a," and "2006b," were identified. Each NoV outbreak epidemic was linked principally to one of these four variants, and there was a time link, a delay of 2 to 6 months, between the first detection of a GII.4 variant and the first outbreak epidemic in which it was the principal variant. The unusual 2006 pattern of outbreak epidemics can then be correlated with the appearance of two GII.4 variants within a short space of time, resulting in two outbreak epidemics in a short space of time, i.e., in the 1 year. This study provides a potentially greater ability to predict the characteristics of NoV epidemics.
诺如病毒（NoV）现在被认为是导致非细菌性肠胃炎爆发的最常见原因，但控制 NoV 发病率的因素知之甚少。2006 年，澳大利亚维多利亚州的 NoV 爆发模式与 2002 年至 2005 年和 2007 年的模式发生了变化。本研究检查了改变的 NoV 周期性的分子相关性。在 2002 年至 2007 年期间，通过逆转录-PCR 对来自 1495 次肠胃炎爆发的 8507 份粪便样本进行了 NoV 检测，并确定了 1018 次 NoV 爆发。核苷酸序列分析用于定义基因型和 GII.4 变体。在 2002 年至 2007 年期间，GII.4 是主要的基因型。在 2002 年至 2005 年和 2007 年期间，每年温暖的月份都会发生一次单一的 NoV 爆发性流行，但在 2006 年，一年内发生了两次流行，一次发生在较冷的月份，一次发生在较温暖的月份。在 2002 年至 2007 年期间，确定了四个主要的 GII.4 变体，“2002 年牛津/法明顿希尔斯”、“2004 年亨特”、“2006a”和“2006b”。每次 NoV 爆发性流行都主要与这四个变体之一有关，并且存在时间联系，即在首次检测到 GII.4 变体与该变体成为主要变体的首次爆发性流行之间存在 2 至 6 个月的延迟。然后，可以将不寻常的 2006 年爆发性流行模式与短时间内出现的两种 GII.4 变体相关联，从而导致短时间内发生两次爆发性流行，即在一年内。本研究提供了一种预测 NoV 流行特征的潜在能力。
