Norovirus introduction routes into nursing homes and risk factors for spread: a systematic review and meta-analysis of observational studies

Norovirus causes substantial morbidity and mortality in nursing homes, with high attack rates in residents and staff. Immediate implementation of infection control measures is crucial. The aim of this review was to assess the evidence for sources and modes of introduction of norovirus, and factors contributing to spread. A systematic review of the literature was performed, including peer-reviewed original studies on outbreaks confirmed by reverse transcriptaseepolymerase chain reaction. Data on source, index case, transmission mode, attack rate, outbreak duration, and risk factors were extracted. Attack rate and outbreak duration were compared by mode of introduction. Based on the selection criteria, 40 outbreak reports and 18 surveillance studies were included. There is little systematic information available on norovirus introduction into nursing homes, but, from evidence obtained from outbreak reports, it was determined that outbreaks often start with single index cases (57.5%), associated with higher attack rates among residents (P = 0.02). Foodborne introduction was described for 7% of outbreak reports that were characterized by finding multiple index cases. In surveillance studies only 0.7% of outbreaks was reported to be foodborne, 28.5% as person-to-person, and 70.8% remained unknown or not mentioned. Risk factor analyses suggested that transmission was associated with bedside care and exposure to vomit. These findings lead to the following recommendations: (i) to standardize outbreak reports; (ii) to improve early detection and isolation of sporadic cases; (iii) to improve personal hygiene of staff especially with highly dependent residents; and (iv) to comply with protocols to avoid exposure to vomit. (C) 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved

The effect of a hand hygiene intervention on infections in residents of nursing homes

Background: The primary goal of hand hygiene is to reduce infectious disease rates. We examined if a nursing home’s participation in a hand hygiene intervention resulted in residents having fewer healthcare associated infections (HAIs) when compared to nursing homes without the hand hygiene intervention. Methods: This study is a part of a cluster randomized controlled trial (RCT) in 33 nursing homes to improve hand hygiene (HANDSOME). The incidence of five illnesses was followed over 13 months: gastroenteritis, influenza-like illness, pneumonia, urinary tract infections and infections from methicillin-resistant Staphylococcus aureus (MRSA). Incidence rates per study arm were reported for baseline (October–December 2016) and two follow-up periods (January–April 2017, May–October 2017). HAI rates were compared in a Poisson multilevel analysis, correcting for baseline differences (the baseline infection incidence and the size of the nursing home), clustering of observations within nursing homes, and period in the study. Results: There was statistically significantly more gastroenteritis (p &lt; 0.001) and statistically significantly less influenza-like illness (p &lt; 0.01) in the intervention arm when compared to the control arm. There were no statistically significant differences or pneumonia, urinary tract infections, and MRSA infections in the intervention arm when compared to the control arm. In a sensitivity analysis, gastroenteritis was no longer statistically significantly higher in the intervention arm (p = 0.92). Conclusions: As in comparable studies, we could not conclusively demonstrate the effectiveness of an HH intervention in reducing HAIs among residents of nursing homes, despite the use of clearly defined outcome measures, a standardized reporting instrument, and directly observed HH in a multicenter cluster RCT. Trial registration Netherlands Trial Register, trial NL6049 (NTR6188). Registered October 25, 2016, https://www.trialregister.nl/trial/6049.</p