Shares of several cruise line companies, including Carnival Corp (NYSE: CCL) Norwegian Cruise Line Holdings Ltd (NYSE: NCLH) and Royal Caribbean Cruises Ltd (NYSE: RCL) are trading lower Wednesday following reports suggesting Royal Caribbean will be extending the suspension of some sailings, including all sailing from the U.S. until June 30.

Cruise line companies are waiting with bated breath for CDC clearance to set sail. While no specific date for resumption was given by the CDC, the public agency repeated how COVID-19 vaccination efforts will be critical in the safe resumption of passenger operations.

The CDC said as more people are fully vaccinated, a phased approach allows the CDC to incorporate advancements into planning for resumption of cruise ship travel when it is safe to do so. The public agency recommends that all eligible port personnel and travelers get a COVID-19 vaccine when one is available to them.

Shares of Carnival, Norweigan and Royal Caribbean are trading lower by 3%, 4% and 2%, respectively, at the time of publication.

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