Single Plane Passenger Gave COVID-19 to 15 Others, CDC Says

According to a study published Friday by the Centers for Disease Control and Prevention, a single passenger spread COVID-19 to 15 other passengers aboard a flight from London, England to Hanoi, Vietnam.

What We Know:

  • In the study, researchers identified a 27-year-old woman from Vietnam who had a sore throat and a cough before the flight as the source of the outbreak. As a result of the March 1 flight, twelve passengers in business class, two passengers in economy, and a crew member were infected. Additionally, upon the women’s arrival in Vietnam, her symptoms progressed further and she tested positive for coronavirus four days later.
  • According to the study, by March 10, contact tracing was conducted for all 217 people aboard the flight. While the people aboard the flight traveled to 15 different provinces in Vietnam, there was no “strong evidence” supporting potential COVID-19 exposure to others outside those on the flight.
  • “The risk for on-board transmission of SARS-CoV-2 during long flights is real and has the potential to cause COVID-19 clusters of substantial size,” the study’s authors wrote. “Our findings call for tightened screening and infection prevention measures by public health authorities, regulators, and the airline industry.”
  • Health officials said at the time of Vietnam Airlines flight’s arrival, passengers and crew members were not required to wear masks at airports or when on airplanes. At the time, all passengers from COVID-19-infected areas, including the United Kingdom, were screened by thermal imaging upon their arrival, but the study does not say whether the woman was flagged for symptoms or not.
  • In its public health guidance, the CDC says that viruses are not easily spread on planes because of the air filtration systems used on them but that sitting within 6 feet of other people and touching frequently used surfaces on long-haul flights can increase the risk of contracting COVID-19. The Washington Post reported that since March, the CDC has found that nearly 11,000 people were exposed to the coronavirus on flights.

The authors of the Vietnam flight study recommended mandatory face coverings, routine hand-washing and testing protocols, and quarantine policies for arriving passengers from countries of high risk.