The CDC has removed its cruise travel warning from its website for cruise passengers who are fully vaccinated, while for unvaccinated passengers the warning has been lowered from Level 4 to Level 3.

The US Centers for Disease Control and Prevention (CDC) had previously advised all Americans against cruise travel, but now says only unvaccinated guests need do so.

The CDC says cruises are now safe for vaccinated passengers

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The CDC website now states that its warning applies only to “travelers who are not fully vaccinated.” It comes as the CDC updates guidance on various economic activities in the US amid the ongoing vaccine roll out.

“Since the virus spreads more easily between people in close quarters aboard ships, the chance of getting COVID-19 on cruise ships is high,” the CDC said on its website.

“It is especially important that people who are not fully vaccinated with an increased risk of severe illness avoid travel on cruise ships, including river cruises.”

Several weeks ago, the CDC said fully vaccinated people don’t have to wear their masks outdoors and in many indoor situations, guidance that was later applied to cruise ships as well.

Masks are still required on planes and inside airports and cruise terminals, regardless of a person’s vaccination status. This rule that has been extended until at least September.

At least 55.8% of Americans 18 and older have received both doses of a vaccine, while 65.4% have received at least one dose, according to the CDC.

The downgrade to Level 3 for unvaccinated passengers comes as the US cruise industry prepares to reopen in July

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According to ABC News, 13 states have vaccinated at least 70% of their adult populations with at least one dose: Pennsylvania, Vermont, Hawaii, New Hampshire, Massachusetts, Connecticut, Maine, New Jersey, Rhode Island, New Mexico, Washington, Maryland, and California.

While updating its guidance on cruises, the CDC also updates its travel guidance for 120 countries. The updated advice offers detailed information on specific countries for travelers who are vaccinated and for those who aren’t.

On the CDC website, cruise passengers can search by the name of the countries their cruise visits to learn whether its COVID-19 risk is very high (Level 4), high (Level 3), moderate (Level 2), low (Level 1), or unknown.

The United Arab Emirates is currently classified as Level 3, as is the Bahamas, Mexico, and Jamaica. A Level 3 warning means only unvaccinated travelers should avoid visiting the countries.