There are few known cases of transmission of coronavirus inside an airplane. Contact tracing after a flight March 31 between the U.S. and Taiwan with 12 symptomatic Covid-19 passengers on board revealed no onboard transmission among 328 other passengers and crew, according to an IATA report. A flight from China to Canada with one symptomatic passenger revealed no onboard transmission. However, preliminary research on a London-to-Vietnam flight on March 2 suggests that one passenger likely infected 14 others, 12 of whom were seated nearby.