Academic journal article Bulletin of the World Health Organization

Effectiveness of Travel Restrictions in the Rapid Containment of Human Influenza: A Systematic review/Efficacite Des Mesures De Restriction Des Deplacements Dans le Confinement Rapide De la Grippe Humaine: Une Revue systematique/La Eficacia De Las Restricciones a Los Viajes En la Contencion Rapida De la Gripe Humana: Una Revision Sistematica

Academic journal article Bulletin of the World Health Organization

Effectiveness of Travel Restrictions in the Rapid Containment of Human Influenza: A Systematic review/Efficacite Des Mesures De Restriction Des Deplacements Dans le Confinement Rapide De la Grippe Humaine: Une Revue systematique/La Eficacia De Las Restricciones a Los Viajes En la Contencion Rapida De la Gripe Humana: Una Revision Sistematica

Article excerpt

Introduction

Travel restrictions were included in the WHO interim protocol: rapid operations to contain the initial emergence of pandemic influenza that was published in 2007 by the World Health Organization (WHO). (1) However, as they would hamper global travel and trade, such restrictions are not recommended by WHO once the global spread of pandemic influenza is established. (2,3) In 2009, some countries applied travel restrictions as one of several strategies to prevent the introduction of the influenza virus A(H1N1)pdm09 into their territories but the effectiveness of this approach has subsequently been questioned. (4) Research on influenza has focused on the evaluation of the effectiveness and impact of pharmaceutical interventions. (5) As quantitative assessment of the effectiveness of travel restrictions in pandemic situations tends to be more challenging, there are scarce data on this topic. In any meta-analysis of surveillance data from multiple studies, it is difficult to quantify and compare the effectiveness of travel restrictions because such interventions are frequently implemented with other countermeasures and without following standardized protocols. (6) However, mathematical models can be used to predict the effectiveness of each type of intervention and inform policy-makers at national and international levels. In 2009, a systematic review of studies based on such models revealed limited evidence of the effectiveness of restrictions in air travel--within and between countries--in the containment of pandemic influenza. (7) There has been no more recent systematic assessment of the effectiveness of restrictions in land, sea or air travel as isolated interventions. We therefore decided to assess the effectiveness of travel restrictions in the rapid containment of influenza strains with pandemic potential, in a systematic review that incorporated data collected during the 2009 pandemic.

Methods

Before commencement, our protocol was registered with PROSPERO--the international prospective register of scientific reviews maintained by the United Kingdom of Great Britain and Northern Irelands National Institute for Health Research. (8) We conducted a systematic review according to the requirements of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. (9) We assessed the evidence for restrictions in internal travel--travel within the same country--or international travel--travel between two or more countries--affecting the spread of influenza. We considered the air, terrestrial or maritime transportation of humans to or within countries affected by seasonal or pandemic influenza. The outcome measures of interest were epidemiological characteristics and some viral transmission parameters of influenza such as the basic reproductive number ([R.sub.0]). Studies eligible for inclusion were reports, reviews, meta-analyses, mathematical modelling studies and observational and experimental studies published before May 2014. Studies that only evaluated the spread of influenza in animals or animal products were excluded.

Search strategy

We searched numerous health-care databases and sources of grey literature (Box 1). Critical keywords and thesaurus heading terms were initially tailored to MEDLINE searches and then adapted for other sources as necessary. The full search construct was included in the registered protocol. (10) We contacted field experts and undertook reference and citation tracking to identify further relevant literature.

Box 1 Sources of literature included in this systematic review
Health-care databases

* CINAHL (Cumulative Index to Nursing and Allied Health Literature)

* Cochrane Library--Central Register of Controlled Trials

* EMBASE

* PubMed--including MEDLINE

* World Health Organization Global Index Medicus

Evidence-based reviews

* Bandolier

* Cochrane Library--Cochrane Database of Systematic Reviews,
Database of Abstracts of Reviews of Effects, Health Technology
Assessment Database, NHS Economic Evaluation Database

Guidelines

* United Kingdom Department of Health

* United Kingdom National Institute for Health Care and
Excellence--Evidence Search

* United States Centers for Disease Control and
Prevention--Guidance

Grey literature

* Consultation with domain experts--Martin Cetron (Centers for
Disease Control and Prevention, Atlanta), John Edmunds (London
School of Hygiene & Tropical Medicine, London), Peter Grove
(Department of Health, London), Richard J Pitman (Oxford Outcomes,
Oxford)

* OpenSIGLE system for information on grey literature in Europe

* United Kingdom National Institute for Health Care and
Excellence--Evidence Search

* Web of Science

Manual searching of relevant journals

* Eurosurveillance

* Emerging Infectious Diseases

Reference tracking

* Reference lists of all studies selected for inclusion were
searched to identify further relevant studies

Citation tracking

* Web of Science--Science Citation Index

* Google Scholar

Internet searching

* www. … 
Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.