Royal Caribbean’s Symphony of the Seas ended a week long cruise in Miami on Saturday, with 48 people on board testing positive for COVID-19, fuelling concerns that the new Omicron variant of the coronavirus could put a damper on a recovery in the cruise industry.

The cruise operator said it had 6,091 guests and crew members on board the ship, which set sail on Dec. 11.

The passengers who tested positive were asymptomatic or mildly symptomatic, Royal Caribbean said in a statement, adding that six guests were disembarked earlier in the cruise and transported home.

Royal Caribbean said 95% of the community on board were fully vaccinated, while 98% of those who tested positive were also fully vaccinated.

The cruise line says Symphony’s future itineraries are not impacted.