The Centers for Disease Control and Prevention on Thursday issued an advisory urging all travelers - vaccinated and unvaccinated - to avoid cruise ship travel amidst a record-breaking Covid surge driven by the omicron variant in many states across the United States.
"Even fully vaccinated travelers may be at risk for getting and spreading COVID-19 variants," the CDC said in a midday bulletin.
The CDC said the travel health notice upgrade from level 3 to level 4 "reflects increases in cases onboard cruise ships since identification of the Omicron variant."
They said more cruise ships are at "level yellow" on a color-coded CDC chart, at which point the public health agency investigates the Covid outbreak on the ship.
"It is especially important that travelers who are at an increased risk of severe illness from COVID-19 avoid travel on cruise ships, including river cruises, worldwide, regardless of vaccination status," they added.
The airline industry has already suffered setbacks from the omicron variant, with Jetblue saying Wednesday it would "proactively" cancel flights through Jan. 13 to get ahead of expected staffing shortages because of spiking Covid rates in the New York City area.
The CDC's cruise ship warning comes after the global cruise industry experienced early Covid outbreaks in early 2020, only to rebound after the availability of vaccines in late 2020.
Over 800 people tested positive and ten people died in early 2020 aboard quarantined cruise ships Diamond Princess and Grand Princess.
After ships and tourists returned to the seas in late 2021, many new policies were introduced in an effort to tamp down the spread of Covid onboard: mandatory vaccinations, negative covid tests and even daily PCR tests for all passengers.
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