They ship has been advertised as a "fully vaxxed" cruise. Apparently, though, now they are updating the reports that there were some unvaxxed children. It's beginning to look like despite being advertised as a "fully vaxxed" cruise it really isn't, no Magoo? This article seems to indicate, BTW, that it is an "and"...both proof of vaccination and testing. This article seems to indicate it is part of the end of cruise testing, and not a requirement for a particular port. A lot of confused reporting going around about this.
Two passengers on the Celebrity Millennium ship carrying vaccinated passengers and crew and some unvaccinated children have tested positive for COVID.
www.usatoday.com