June 10 (UPI) -- Two people tested positive for COVID-19 while aboard a Celebrity cruise where all crew and passengers were required to be fully vaccinated, the cruise line said Thursday.
Celebrity issued a statement announcing two passengers who were sharing a stateroom on the Celebrity Millennium tested positive for the virus at the "end-of-cruise" testing 72 hours before the ship returns to the United States.
"The individuals are asymptomatic and currently in isolation and being monitored by our medical team," the cruise line said. "We are conducting contact tracing, expediting testing for all close contacts and closely monitoring the situation."
The cruise line said that all crew and passengers aboard the ship were required to be vaccinated and passengers were required to show proof of vaccination and a negative COVID-19 test before sailing from St. Maarten last Saturday.
It added that the ship was also following "comprehensive protocols that align with our destination partners and exceed CDC guidelines."
The cruise was the first to depart with U.S. passengers since the COVID-19 pandemic caused the cruise industry to shut down last year.
Celebrity last month said it is also poised to become the first cruise line to sail from the United States when the Celebrity Edge is set to depart from Port Everglades in Fort Lauderdale, Fla., on June 26.
Celebrity Cruises said it will follow CDC guidance and require that at least 95% of crew and passengers are vaccinated before they can board to ship on that trip.