STOPFLU: is it possible to reduce the number of days off in office work by improved hand-hygiene?

Abstract

BackgroundAcute infectious diseases are major causes of short periods of days off from work, day care and school. These diseases are mainly caused by viruses and hands have a key role in their transmission. Thus, hypothetically, they can be controlled with means of intensified hand hygiene. In this study we aim to elucidate the effect of acute infectious diseases on the work contribution in common office work and study the influence of improved hand hygiene on possible reduction of infectious disease episodes and days off from work due to acute infectious diseases.DesignThe voluntary participants have been recruited from six companies in the Helsinki region. The designated 21 study clusters were identified as operationally distinct working units each containing at least 50 people. The clusters were matched and randomized based on results of a pre-trial contagion risk survey. Improved hand hygiene is being executed with guided hand-washing with soap and water in one intervention arm and with alcohol based hand rubbing disinfectant in the other. Participants in both arms have received guidance on how to avoid infections and how to implement contagion stopping habits. A control arm is acting as before regarding hand hygiene. Data collection for evaluation of the efficacy of the interventions is based on self-reporting through weekly electronic reports. The questionnaire is enquiring about possible respiratory or gastrointestinal symptoms during the preceding week, and requests a daily report of presence of symptoms and working capacity. Etiology of the symptoms is not searched for individually, but contribution of different viruses is evaluated by sentinel surveillance, where occupational health clinics located in the premises of the participating companies collect specimens from employees visiting the clinic. Common causative agents of the diseases are being searched for using real-time PCR techniques. The duration of the intervention will be 16 months. Primary endpoints of the study are the number of reported infection episodes in a cluster within a time frame of 100 reporting weeks and the number of reported sick leave episodes in a cluster within a time frame of 100 reporting weeks.Trial RegistrationClinicalTrials.gov Identifier: NCT00821509

Intensified hand-hygiene campaign including soap-and-water wash may prevent acute infections in office workers, as shown by a recognized-exposure -adjusted analysis of a randomized trial

“…In open community settings, the evidence for efficacy has been considered inconclusive [9, 10], and both positive effects [11] and lack of efficacy [12] have been reported in more recent studies. This divergence of the published results may be partly due to the multitude of difficult to control intervention-unrelated factors potentially affecting the outcome of the trial [13], which may result in a failure to identify all relevant factors that could be used in pre-randomization stratification of the population in order to improve arm matching. In addition, post-randomization emergence of unexpected confounding factors may complicate the analysis of the results.…”

Development of a prognostic model based on demographic, environmental and lifestyle information for predicting incidences of symptomatic respiratory or gastrointestinal infection in adult office workers

“…1. As described previously by Savolainen-Kopra et al [6] the information on designated infection-risk factors among the volunteer participants was collected through a standardized questionnaire. Its use for trial-arm harmonization in the original trial is described in Additional file 1.…”

“… a Slightly modified from the original (Savolainen-Kopra et al [6]) and simplified by omitting some details (Additional file 1)…”

“…The model was fitted to the individual level time-aggregated data taking into account the designated clusters and prerandomization matching in the data using random effects. The intervention arm was included in the model by adjusting its influence when estimating the effect of the baseline covariates age, gender, and the designated risk factors of the background trial [6] (Table 1). The negative binomial model allows estimating of the heterogeneity of individuals reflected in the autocorrelation and over-dispersion in the standard Poisson regression model [8, 9].…”

“…Occurrence of symptoms of RTI or GTI and that of recognized exposures to other persons with symptoms of RTI or GTI, were collected by weekly electronic reports. The protocol and the main results of the trial have been published before [6, 7], and selected parts are described in Additional file 1. In order to be able to homogenize the study arms in the original trial, interview data for various designated risk factors for acute infection were collected from the volunteer participants.…”