Seems either transmitted by a contaminated crew member preparing...

Seems either transmitted by a contaminated crew member preparing or serving food /drinks (..most likely) or heaven forbid its airborne in the A/c system which all rooms on a deck might share.

Seems mighty suspicious that so many are getting it under lock down on this boat. Unfortunately most of the people on these cruises seem to be the elderly with low immunity to bugs. Having been on a few cruises I know they use loads of alcohol based hand sanitiser. Perhaps its not working as well as say HCT's Natshield would. !!