The Celebrity Millennium became the first ship to sail with guests from North America in more than a year.

The passengers, who shared a room on the Celebrity Millennium, tested positive during the end-of-cruise testing which is completed three days before returning to the US.

"We are conducting contact tracing, expediting testing for all those close contacts, and closely monitoring the situation."

All passengers were required to show proof of vaccination along with a negative Covid-19 test within 72-hours before the ship departed.

https://www.the-sun.com/news/3057850/celebrity-millennium-passengers-vaccinated-america-covid-positive/