Effectiveness of travel restrictions in the rapid containment of human influenza: a systematic review

Abstract

ObjectiveTo assess the effectiveness of internal and international travel restrictions in the rapid containment of influenza.MethodsWe conducted a systematic review according to the requirements of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Health-care databases and grey literature were searched and screened for records published before May 2014. Data extraction and assessments of risk of bias were undertaken by two researchers independently. Results were synthesized in a narrative form.FindingsThe overall risk of bias in the 23 included studies was low to moderate. Internal travel restrictions and international border restrictions delayed the spread of influenza epidemics by one week and two months, respectively. International travel restrictions delayed the spread and peak of epidemics by periods varying between a few days and four months. Travel restrictions reduced the incidence of new cases by less than 3%. Impact was reduced when restrictions were implemented more than six weeks after the notification of epidemics or when the level of transmissibility was high. Travel restrictions would have minimal impact in urban centres with dense populations and travel networks. We found no evidence that travel restrictions would contain influenza within a defined geographical area.ConclusionExtensive travel restrictions may delay the dissemination of influenza but cannot prevent it. The evidence does not support travel restrictions as an isolated intervention for the rapid containment of influenza. Travel restrictions would make an extremely limited contribution to any policy for rapid containment of influenza at source during the first emergence of a pandemic virus.

Inflow restrictions can prevent epidemics when contact tracing efforts are effective but have limited capacity

“…T Chinazzi et al study the effect of reducing the inflow of infected individuals while simultaneously reducing in the community at large and also find that inflow reduction has only a marginal delay effect unless is reduced drastically (2). These pessimistic findings reflect those from a large number of earlier models (3)(4)(5)(6)(7)(8). The World Health Organization's 2014 Systematic Review on the role of travel restrictions in containing pandemic influenza reviewed 20 23 papers and concluded that a 90% reduction in international air travel would only slow down a pandemic by 3-4 weeks and would not prevent the introduction of a pandemic into any given country (9).…”

Do not violate the International Health Regulations during the COVID-19 outbreak

“…No one will be untouched by climate change, but it is not experienced equally. 5 Affluent people can afford to live in insulated buildings with air conditioning and air purifiers. The poor, older people, people with disabilities, and those with pre-existing health conditions are the least able to adapt to the changing climate, unable to escape the fires and heat, and live in dwellings and environments that amplify its effects.…”

“…1 Many of the travel restrictions being implemented during the COVID-19 outbreak are not supported by science or WHO. Travel restrictions for these kinds of viruses have been challenged by public health researchers, [4][5][6] and WHO has advised against travel restrictions, arguing they cause more harm than good. 7,8 Second, under Article 43.1 any additional health measures implemented by countries "shall not be more restrictive of international traffic and not more invasive or intrusive to persons than reasonably available alternatives".…”

“…But evidence belies the claim that illegal travel restrictions make countries safer. [4][5][6] In the short term, travel restrictions prevent supplies from getting into affected areas, slow down the international public health response, stigmatise entire populations, and disproportionately harm the most vulnerable among us. In the longer term, countries selecting which international laws to follow encourages other countries to do the same, which in turn undermines the broader rules-based world order.…”

Modelling the global spread of diseases: A review of current practice and capability

“…Confidence in model accuracy may be increased if multiple different, independent models, developed by independent research groups, converge on a qualitatively similar output (or they may provide clear insight to the reasons for different qualitative behaviour). For example, Mateus and Otete (2014) found that multiple models offer the same qualitative prediction that travel restrictions will not prevent the spread of influenza into susceptible populations. According to Keeling and Rohani (2008), a good model should be both suited to its purpose (as simple as possible but no simpler) and parameterizable by available data.…”