In an apparent attempt to reach a compromise with US lawmakers, the Centers for Disease Control and Prevention (CDC) has issued an advisory warning Americans against cruise travel, just days after rescinding its own No Sail Order.

The CDC issued a Level 4 warning for cruise travel, up from Level 3, meaning it feels there is a “very high level of COVID-19” risk aboard cruise ships, after cancelling its No Sail Order for cruise lines and introducing a Conditional Framework for a return to service.

The Conditional Framework enables each cruise line to be individually assessed for compliance by the CDC.

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“CDC recommends that all people avoid travel on cruise ships, including river cruises, worldwide, because the risk of COVID-19 on cruise ships is very high. It is especially important that people with an increased risk of severe illness avoid travel on cruise ships, including river cruises,” the agency said, in a statement on its website.

The decision to increase the travel warning, and advise Americans against going on cruise ships, appears to be an attempt by the US’ top health authority to reach a compromise with lawmakers that had written to the authority asking it to reinstate the cruise ban.

On November 13^th, a Senator and Congresswoman signed a joint letter to CDC Director Robert R. Redfield, asking him to bring back the No Sail Order after five passengers aboard SeaDream 1 tested positive for COVID-19 in the Caribbean.

“We write with urgent concern surrounding recent reports of multiple confirmed positive COVID-19 cases on board the first cruise ship to carry passengers in the Caribbean since  countries around the world imposed strict limitations on operations in mid-March,” the letter said.

The CDC head office in Atlanta.

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“The order set out a seemingly robust and phased approach to restarting cruise line operations, but we have serious concerns that – even with the additional requirements and standards – cruising is simply unsafe during a global pandemic,” it added.

While the CDC has indicated that dozens of cruise ships operating from the United States, prior to the No Sail Order, had reported coronavirus outbreaks, the cruise lines have argued that the closed nature of a cruise ship’s manifest, compared to a hotel, where guests come and go each day, lends itself to the early diagnosis of COVID-19 cases.

However, CDC Director Robert R. Redfield was himself opposed to ending the No Sail Order before the first quarter of 2021, but was reportedly strong-armed by the White House into developing a framework for cruise ships to return to service.

The CDC’s latest advice says that passengers who decide to go on a cruise should get tested three to five days after their trip and stay home for seven days after travel. This is in addition to the mandatory pre-cruise COVID-19 testing that will be required by cruise lines when they resume cruises from the US.

The CDC said that even if someone tests negative, they should stay home for the full seven days. The CDC also said if a guest doesn’t get tested, it’s safest to stay home for 14 days after travel. The travel advisory is aimed only at passengers embarking in US ports, and does not affect cruises that have resumed in the Mediterranean and elsewhere.