Background: COVID-19 has proven to be more difficult to manage for many reasons including its high infectivity rate. One of the potential ways to limit its spread is by controlling free international travel. The objective of this systematic review is to identify, critically-appraise and summarize evidence on international travel-related control measures.
Methods: This review is based on the Cochrane review: International travel-related control measures to contain the COVID-19 pandemic and followed the same methods. In brief, we searched for clinical and modelling studies in general health and COVID-19-specific bibliographic databases. The primary outcome categories were (i) cases avoided, (ii) a shift in epidemic development and, (iii) cases detected. Secondary outcomes were other infectious disease transmission outcomes, healthcare utilisation, resource requirements and adverse effects if identified in studies assessing at least one primary outcome.
Results: We assessed 66 full-text articles that met with our inclusion criteria. Seventeen new studies (modelling = 9, observational = 8) were identified in the updated search. Most studies were of critical to moderate risk of bias. The added studies did not change the main conclusions of the Cochrane review nor the quality of the evidence (very low to low certainty). However, it did add to the evidence base for most outcomes.
Conclusions: Weak evidence supports the use of international travel-related control measures to limit the spread of COVID-19 via air travel. Real-world studies are required to support these conclusions.