A high attack rate of 90% of SARS-CoV-2 Delta variant infections in crew personnel on a single navy ship.

272 soldiers out of the 301 soldiers (90.4%) were infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant of concern (VOC) on a single navy ship. This outbreak provides three lessons for the pandemic. This incident clearly demonstrates the transmission characteristics of the SARS-CoV-2 Delta VOC.