Open AccessThe impact of vaccination status on importation of COVID-19 among international travellers
Author(s) -
Paul E. Ronksley,
Tayler Scory,
R. Glenn Weaver,
Meaghan Lunney,
Rachel Rodin,
Marcello Tonelli
Publication year - 2021
Publication title -
canada communicable disease report
Language(s) - English
Resource type - Journals
eISSN - 1481-8531
pISSN - 1188-4169
DOI - 10.14745/ccdr.v47i11a05
Subject(s) - covid-19 , vaccination , quarantine , government (linguistics) , public health , medicine , pandemic , environmental health , population , business , disease , virology , infectious disease (medical specialty) , outbreak , linguistics , philosophy , nursing , pathology
Governments worldwide are looking for ways to safely enable international travel while mitigating the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the associated coronavirus disease 2019 (COVID-19). However, few data describe the impact of vaccination on importation of COVID-19. We took advantage of the sequential introduction of two government policies in Canada to evaluate the real-world evidence of vaccine effectiveness among 30,361 international travellers arriving by air in Alberta, Canada. The proportion of COVID-19-positive results for travellers who were either fully vaccinated or partially vaccinated was 0.02% (95% CI: 0.00–0.10) (i.e. one positive case among 5,817 travellers). In contrast, 1.42% (95% CI: 1.27–1.58) of unvaccinated travellers tested positive for SARS-CoV-2 (341 cases among 24,034 travellers). These findings suggest that COVID-19 vaccinations approved in Canada, substantially reduced the risk of travel-related importation of COVID-19 when combined with other public health measures. The low absolute rate of infection among fully vaccinated or partially vaccinated international travellers may inform quarantine requirements in this population.