The use of quarantine as an international travel measure during the COVID-19 pandemic: A comparative analysis of implementation and equity impacts in five "exemplar" countries.

During the COVID-19 pandemic, virtually all countries used a range of measures to mitigate the risks of virus introduction and onward transmission via international travel. Quarantine was a key international travel measure (ITM) used by governments to achieve public health goals. However, the highly varied ways in which quarantine was implemented makes lesson learning for future pandemics challenging. Moreover, most studies overlook the secondary impacts of ITMs on individuals and populations including potential inequities in their distribution. This paper comparatively analyses five countries deemed exemplary in their implementation of quarantine during COVID-19. Building on Damschroder's Consolidated Framework for Implementation Research, we apply eight variables to identify similarities and differences in quarantine use. We drew on our standardized coding of ITMs in the WHO Public Health and Social Measures dataset, and additional on-line searches, to compile data on each variable. Findings show that the five countries were early adopters of quarantine, applied them relatively stringently, and maintained them throughout the emergency phase of the pandemic to effectively advance public health goals. However, the countries differed in how secondary impacts were managed, resulting in the inequitable distribution of opportunity and burden for some individuals and populations. We conclude that exemplary implementation of quarantine during future public health emergencies should consider both public health goals and the equity of secondary impacts.