Epidemiology and impact of norovirus outbreaks in Norwegian healthcare institutions, 2005–2018

Abstract

The aim of this study was, for the first time, to describe in detail the epidemiology and impact of norovirus outbreaks in healthcare institituions (HCIs) in Norway to identify areas which may improve outbreak response. Methods: An analysis of all reported norovirus outbreaks in hospitals and long-term-care facilities (LTCFs) was carried out from week 34, 2005 to week 33, 2018. Seasonality, symptoms and number of cases among personnel and patients were described. Findings: A total of 20,544 cases, including 7044 healthcare personnel were reported in 965 outbreaks; 740 from LTCFs and 225 from hospitals. Median number of cases per outbreak was 15, interquartile range (IQR) 8e25 in LTCF; and 17, IQR 10e28 in hospitals. All regions reported outbreaks, with one-third of the municipalities having at least one outbreak in LTCFs during the study period. The start of the outbreak season happened almost four weeks earlier in hospitals than in LTCFs. The estimated average number of working days lost for healthcare personnel per year ranged from 1590 to 1944. Conclusions: Norovirus outbreaks in Norwegian HCIs appears to have a substantial impact on both hospital and LTCFs all over Norway, especially during the winter months. That up to half of all cases were healthcare professionals emphasizes a need for further focus on infection control. Our results suggest that hospitals, affected first, could alert LTCFs in the area in order to prevent further outbreaks.

Epidemiology of gastrointestinal infections: lessons learned from syndromic testing, Region Zealand, Denmark

“…The number of coinfections in the present study is higher than in two distinct Italian and French pediatric studies where coinfections were only detected in 8.3% and 3.3% of virus-positive patients, respectively [14,15]. In these studies, viruses were mostly detected by EIA and ELISA and some of the differences season, fewer coinfections, and also many cases in adults, where family and small general outbreaks including foodborne outbreaks are well known to occur [16].…”

“…Sapovirus had a unique age-specific profile with a modest number of infections occurring beyond 10 years of age. Norovirus had a completely different epidemiology with a long winter season, fewer coinfections, and also many cases in adults, where family and small general outbreaks including foodborne outbreaks are well known to occur [ 16 ].…”

Norovirus outbreaks in long-term care facilities. Catalonia, 2017-2018

“…Inns et al described 566 AGE outbreaks in LTCF in North East England between 2016 and 2018 and norovirus was detected in 64% of outbreaks with a pathogen identi ed26 . Steele et al studied 7,094 norovirus outbreaks between 2009 and 2017 in United States of which 5,335 (75%) occurred in LTCF27 and Espenhain et al found that 77% of norovirus outbreaks in Norway between 2005 and 2018 were in LTCF28 .A seasonal distribution was observed, with most of outbreaks occurring in autumn and winter. Our results are consistent with previous ndings by other authors indicating a seasonality of norovirus disease4,28 .…”