Study shows pre-flight Covid-19 testing reduces onboard infection rate

Study shows pre-flight Covid-19 testing reduces onboard infection rate

The risk of transmission could be less than one in one million, says Delta chief health officer

A newly released study – conducted by Delta, The Georgia Department of Health and the Mayo Clinic in the US – shows that pre-flight testing for Covid-19 could decrease on board infections “to a level that is significantly below active community infection rates”. This suggests, with mandatory pre-flight testing, people are less likely to catch Covid on a plane than they are in their own community.

The peer-reviewed study used real-world data from 10,000 travellers using Delta’s Covid-tested flights between New York JFK, Atlanta and Rome Fiumicino, and found that the risk of exposure following a negative PCR test 72 hours before a flight is less than 0.1%. 

The study also showed that the routine use of a single molecular test within 72 hours before international travel for unvaccinated individuals significantly mitigates the risk of Covid-19 exposure and transmission during air travel.

An example given was where the average community infection rate was at 1.1%  (about one in 100 people), but the infection rate on Covid-19 tested flights was just 0.05% (five in 10,000 passengers).


Delta chief health officer Dr Henry Ting said: “We are going to live with Covid-19 variants for some time. This real-world data – not simulation models – is what governments around the world can use as a blueprint for requiring vaccinations and testing, instead of quarantines, in order to re-open borders for international travel.”

Ting went on to say that air travel risk will vary depending on multiple factors, including case rates and vaccination rates at the origin and destination, and masks being mandatory on board, adding: “When you couple the extremely low infection rate on board a Covid-19-tested flight with the layers of protection on board, including mandatory masking and hospital-grade air filtration, the risk of transmission is less than one in one million between the United States and the United Kingdom, for example. The numbers are set to continue improving as vaccination rates increase and new cases decrease worldwide.”

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