Effect of Predeparture Testing on Postarrival SARS-CoV-2–Positive Test Results Among International Travelers — CDC Traveler-Based Genomic Surveillance Program, Four U.S. Airports, March–September 2022

Abstract

What is already known about this topic? During December 6, 2021–June 11, 2022, SARS-CoV-2 testing ≤1 day before departure or proof of recent COVID-19 recovery were required for passengers boarding U.S.-bound flights. Mathematical models have estimated predeparture testing effectiveness in preventing travel-associated transmission. What is added by this report? CDC’s Traveler-based Genomic Surveillance Program collects postarrival nasal swabs for SARS-CoV-2 testing from volunteering international air travelers. Among 3,049 pooled (28,056 individual) samples collected during March 20–September 3, 2022, the predeparture testing requirement was associated with 52% lower postarrival SARS-CoV-2 positivity. What are the implications for public health practice? Predeparture testing can reduce SARS-CoV-2 transmission risk during or after travel by reducing the number of infectious travelers. These results can help guide decisions for future outbreaks.