Transmission of SARS-CoV-2 During Air Travel: A Descriptive and Modelling Study

Abstract Background Millions of cases of the novel coronavirus disease 2019 (COVID-19) have been reported in the world. Although it is known that the air travel has the potential to spread SARS-CoV-2, the risk of in-flight transmission is unknown.Methods We enrolled all passengers and crew suspected of being infected with SARS-CoV-2, who bounded for Beijing on international flights. We specified the characteristics of all confirmed cases of COVID-19 infection and utilized Wells-Riley equation to estimate the infectivity of COVID-19 during air travel.Results We screened 4492 passengers and crew with suspected COVID-19 infection, verified 161 confirmed cases (mean age 28.6 years), and traced two confirmed cases who may have been infected in the aircraft. The estimated infectivity was 375 quanta/h (range 274-476), while the effective infectivity was only 4 quanta/h (range 2-5). The risk of per-person infection during a 13 hours air travel in economy class was 0.56‰ (95% CI 0.41‰-0.72‰). Conclusion We found that the universal use of face masks on the flight, together with the plane's ventilation system, significantly decreased the infectivity of COVID-19.