Is it Safe to Fly During the COVID-19 Pandemic?
Should you pack your bags? What does the evidence say?
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On the surface, air travel seems like a recipe for COVID-19 disaster — a bunch of strangers packed like sardines into a small space, sharing the same smelly air. Yet, recent news headlines and government policies, suggest that in-flight risks may be smaller than feared.
“Flying can be safer than grocery shopping, Harvard study asserts”. CNN
Is COVID-19 truly not spreading on board airplanes? Or, are industry and government agencies downplaying the risks associated with travel, for economic reasons? Let’s take a look at the evidence.
How likely is it that I will get COVID-19 from flying?
Boarding an airplane clearly increases your “exposure risk” — the risk that you will be exposed to someone with COVID-19 (see Appendix for sample calculation). Indeed, many public health agencies have mounted dashboards that publicly track in-flight exposures (eg. Canadian flight exposures, and British Columbia flight exposures).
Yet, getting exposed to COVID-19 is not the same as getting it. To pass along COVID-19, the infectious person must spew out viral particles, and a critical mass of those particles need to make it into the airways of a fellow passenger. The likelihood that this happens is called the “transmission risk”.
The transmission risk of COVID-19 is tough to pin down, as it varies greatly depending on many factors, including the environment, the individuals involved, and the risk-mitigation practices.
How likely is it that an infected airplane passenger will spread it to others?
The emerging consensus as of November 2020 is that on-board transmission risk is low. In other words, most COVID-19 cases do not spread to other passengers, but once in a while, we get unlucky. This conclusion rests on two lines of evidence, documented outbreaks and documented lack of transmission, each of which come with…