Two passengers sharing the same stateroom on board the first North American cruise since 2020 tested positive for COVID-19 on Thursday.
All crew and adult passengers on board the Celebrity Millennium had to show proof that they were fully vaccinated as well as provide a negative COVID-19 test prior to or at the time of boarding.
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The passengers found out they were positive while undergoing testing before disembarking the ship in St. Maarten.
"The individuals are asymptomatic and currently in isolation and being monitored by our medical team," the cruise line said in a statement to ABC News. "We are conducting contact tracing, expediting testing for all close contacts and closely monitoring the situation."