Physical interventions to interrupt or reduce the spread of respiratory viruses: Systematic review

Cochrane Vaccines Field, Alessandria, Italy.
BMJ (online) (Impact Factor: 17.45). 02/2008; 336(7635):77-80. DOI: 10.1136/bmj.39393.510347.BE
Source: PubMed


To systematically review evidence for the effectiveness of physical interventions to interrupt or reduce the spread of respiratory viruses.
Search strategy of the Cochrane Library, Medline, OldMedline, Embase, and CINAHL, without language restriction, for any intervention to prevent transmission of respiratory viruses (isolation, quarantine, social distancing, barriers, personal protection, and hygiene). Study designs were randomised trials, cohort studies, case-control studies, and controlled before and after studies.
Of 2300 titles scanned 138 full papers were retrieved, including 49 papers of 51 studies. Study quality was poor for the three randomised controlled trials and most of the cluster randomised controlled trials; the observational studies were of mixed quality. Heterogeneity precluded meta-analysis of most data except that from six case-control studies. The highest quality cluster randomised trials suggest that the spread of respiratory viruses into the community can be prevented by intervening with hygienic measures aimed at younger children. Meta-analysis of six case-control studies suggests that physical measures are highly effective in preventing the spread of SARS: handwashing more than 10 times daily (odds ratio 0.45, 95% confidence interval 0.36 to 0.57; number needed to treat=4, 95% confidence interval 3.65 to 5.52); wearing masks (0.32, 0.25 to 0.40; NNT=6, 4.54 to 8.03); wearing N95 masks (0.09, 0.03 to 0.30; NNT=3, 2.37 to 4.06); wearing gloves (0.43, 0.29 to 0.65; NNT=5, 4.15 to 15.41); wearing gowns (0.23, 0.14 to 0.37; NNT=5, 3.37 to 7.12); and handwashing, masks, gloves, and gowns combined (0.09, 0.02 to 0.35; NNT=3, 2.66 to 4.97). The incremental effect of adding virucidals or antiseptics to normal handwashing to decrease the spread of respiratory disease remains uncertain. The lack of proper evaluation of global measures such as screening at entry ports and social distancing prevent firm conclusions being drawn.
Routine long term implementation of some physical measures to interrupt or reduce the spread of respiratory viruses might be difficult but many simple and low cost interventions could be useful in reducing the spread.

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    • "According to the WHO recommendations in case of epidemics and pandemics, along with other preventive measures to protect human health, one of the key measures is the implementation of respiratory protection [12] [13]. At the individual level, respiratory protection is achieved by wearing different types of masks, half masks, respirators or other physical barriers [14]. "

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    • "With effective control measures such as early detection and targeted segregation, many infectious diseases can be contained (WHO, 2003; Connolly et al., 2004; Lau et al., 2004ab). Jefferson et al. (2008) felt that systematic education on personal hygiene and physical interruptions (e.g. immediate isolation of infected patients) are important in preventing rapid dispersal of respiratory diseases. "
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    ABSTRACT: This study describes the development of a spatio-temporal disease model based on the episodes of severe acute respiratory syndrome (SARS) that took place in Hong Kong in 2003. In contrast to conventional, deterministic modelling approaches, the model described here is predominantly spatial. It incorporates stochastic processing of environmental and social variables that interact in space and time to affect the patterns of disease transmission in a community. The model was validated through a comparative assessment between actual and modelled distribution of diseased locations. Our study shows that the inclusion of location-specific characteristics satisfactorily replicates the spatial dynamics of an infectious disease. The Pearson's correlation coefficients for five trials based on 3-day aggregation of disease counts for 1-3, 4-6 and 7-9 day forecasts were 0.57- 0.95, 0.54-0.86 and 0.57-0.82, respectively, while the correlation based on 5-day aggregation for the 1-5 day forecast was 0.55- 0.94 and 0.58-0.81 for the 6-10 day forecast. The significant and strong relationship between actual results and forecast is encouraging for the potential development of an early warning system for detecting this type of disease outbreaks.
    Geospatial health 11/2013; 8(1):183-192. DOI:10.4081/gh.2013.65 · 1.19 Impact Factor
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    • "Previous educational interventions in school settings have been associated with reduced absenteeism [8,9] and gastrointestinal infections [10], and increased compliance with hand washing [11,12]. Reviews of interventions to promote hand washing, including several studies in school settings, concluded that the interventions were associated with reduced respiratory infections, but that the studies were generally poor quality [13,14]. Interventions to improve water quality, hygiene behaviours and sanitation in schools have also been shown to reduce absence among primary school pupils in developing countries [15]. "
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    ABSTRACT: Process evaluations are useful for understanding how interventions are implemented in trial settings. This is important for interpreting main trial result s and indicating how the intervention might function beyond the trial. The purpose of this study was to examine the reach, dose, fidelity, acceptability, and sustainability of the implementation of an educational hand washing intervention in primary schools, and to explore views regarding acceptability and sustainability of the intervention. Process evaluation within a cluster randomised controlled trial, including focus groups with pupils aged 6 to 11, semi-structured interviews with teachers and external staff who coordinated the intervention delivery, and school reports and direct observations of the intervention delivery. The educational package was delivered in 61.4% of schools (85.2% of intervention schools, 37.8% of control schools following completion of the trial). Teachers and pupils reacted positively to the intervention, although concerns were raised about the age-appropriateness of the resources. Teachers adapted the resources to suit their school setting and pupils. Staff coordinating the intervention delivery had limited capacity to follow up and respond to schools. The hand washing intervention was acceptable to schools, but its reach outside of a randomised trial, evidenced in the low proportion of schools in the control arm who received it after the trial had ended, suggests that the model of delivery may not be sustainable. Trial registration: ISRCTN: ISRCTN93576146.
    BMC Public Health 08/2013; 13(1):757. DOI:10.1186/1471-2458-13-757 · 2.26 Impact Factor
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