Surveillance of International Travel of COVID-19 Cases (SuITCases) in England

Abstract

Introduction: The emergence of SARS-CoV-2 variants necessitated identification of travel-associated COVID-19 cases in England. Methods: We implemented a novel integrated COVID-19-episode-level travel surveillance system, Surveillance of International COVID-19 Cases (SuITCases), to assign imported, sporadic or unknown travel status to COVID-19 cases, using data linkage between two enhanced and two routine data sources. Results: SuITCases identified 517,988 travel-associated SARS-CoV-2 episodes (3.0% of total), where the two enhanced systems assigned most travel statuses. Conclusions: Our unique system facilitated rapid identification of travel-associated COVID-19 cases, reducing transmission and informing public health actions. Enhanced surveillance data sources should be considered as potential tools for future outbreak investigations and pandemic preparedness.