Four persons with severe acute respiratory syndrome coronavirus 2 infection had traveled on the same flight from Boston, Massachusetts, USA, to Hong Kong, China. Their virus genetic sequences are identical, unique, and belong to a clade not previously identified in Hong Kong, which strongly suggests that the virus can be transmitted during air travel.
Keywords: 2019 novel coronavirus disease; COVID-19; SARS-CoV-2; air travel; aircraft; case reports; coronavirus disease; disease transmission; epidemiologic studies; genome; infectious; respiratory infections; severe acute respiratory syndrome coronavirus 2; viral; viruses; whole-genome sequencing; zoonoses.