Preflight Covid-19 testing is on the rise — the question is whether it works

Starting Oct. 15, American Airlines’ passengers traveling from Dallas-Fort Worth International Airport to Hawaii and Costa Rica can take Covid-19 tests at …

Research conducted by IATA shows that 65% of travelers believe people who test negative for Covid-19 should not be required to quarantine. Health care professionals, however, aren’t so optimistic.

“A preflight test, even when given at the security checkpoint, is not a foolproof protocol to prevent the spread of Covid-19 to the passenger’s destination site,” said Dr. Makeda Robinson, a virologist at Stanford University.

Robinson said every person infected with Covid-19 has an incubation period when the virus can’t yet be detected by tests. The average is four to seven days, but it can run as long as 14 days in some people, she said.

“For comparison, with the 2003 SARS virus, people tended to be most infectious after they developed symptoms, making it easier to identify cases and separate them from the unexposed population,” she said. “However, SARS-CoV-2 [Covid-19] has more asymptomatic infections and can be highly infectious prior to symptom onset.”

“This means that someone could be infected, … have an initial test which was negative prior to boarding the plane, and then test positive in the days following their flight,” Robinson said.