Curran Evonne T, Wilson Jennie, Haig Caroline E, McCowan Colin, Leanord Alistair, Loveday Heather
Health Protection Scotland, UK.
Richard Wells Research Centre, University of West London, UK.
J Infect Prev. 2016 Jan;17(1):8-14. doi: 10.1177/1757177415613133. Epub 2015 Oct 28.
Norovirus outbreaks have a significant impact on all care settings; little is known about the index cases from whom these outbreaks initiate.
To identify and categorise norovirus outbreak index cases in care settings.
A mixed-methods, multi-centre, prospective, enhanced surveillance study identified and categorised index cases in acute and non-acute care settings.
From 54 participating centres, 537 outbreaks were reported (November 2013 to April 2014): 383 (71.3%) in acute care facilities (ACF); 115 (21.4%) in residential or care homes (RCH) and 39 (7.3%) in other care settings (OCS). Index cases were identified in 424 (79%) outbreaks. Of the 245 index cases who were asymptomatic on admission and not transferred within/into the care setting, 123 (50%) had been an inpatient/resident for 4 days. Four themes emerged: missing the diagnosis, care service under pressure, delay in outbreak control measures and patient/resident location and proximity.
The true index case is commonly not identified as the cause of a norovirus outbreak with at least 50% of index cases being misclassified. Unrecognised norovirus cross-transmission occurs frequently suggesting that either Standard Infection Control Precautions (SICPs) are being insufficiently well applied, and or SICPs are themselves are insufficient to prevent outbreaks.
诺如病毒暴发对所有护理机构都有重大影响；对于这些暴发最初源自的指示病例知之甚少。
识别并分类护理机构中的诺如病毒暴发指示病例。
一项采用混合方法的多中心前瞻性强化监测研究对急性和非急性护理机构中的指示病例进行了识别和分类。
在2013年11月至2014年4月期间，来自54个参与中心报告了537起暴发：383起（71.3%）发生在急性护理机构（ACF）；115起（21.4%）发生在养老院或护理院（RCH），39起（7.3%）发生在其他护理机构（OCS）。在424起（79%）暴发中识别出了指示病例。在入院时无症状且未在护理机构内/转入护理机构的245例指示病例中，123例（50%）已住院/入住4天。出现了四个主题：漏诊、护理服务面临压力、暴发控制措施延迟以及患者/居民的位置和接近程度。
真正的指示病例通常未被确定为诺如病毒暴发的原因，至少50%的指示病例被错误分类。未被识别的诺如病毒交叉传播频繁发生，这表明要么标准感染控制预防措施（SICPs）应用得不够充分，要么SICPs本身不足以预防暴发。
