91 cruise ships under CDC investigation following COVID outbreaks

• The industry, which was an early epicenter for coronavirus outbreaks, staged a comeback in September, with several preventative measures in place to curb the spread of the virus.

Driving the news: The CDC is investigating 26 ships and is observing 65 ships following earlier investigations, according to the agency's latest update.

• The affected cruise lines include Disney, Carnival, Royal Caribbean and Norwegian.
• The CDC also said Thursday that passengers should "avoid cruise ships, regardless of vaccination status," citing an increased threat of COVID-19.

Worth noting: An additional three ships are being monitored due to reported COVID infections, though case numbers are below the agency's threshold to start an investigation — cases reported in more than 0.10% of passengers or a single crew member in the previous seven days.

What they're saying: "The Cruise Lines International Association (CLIA) and our members ... continue to have very productive dialogue and are working together with the CDC in the interest of public health and safety," Anne Madison, a spokesperson for the Cruise Lines International Association, said in a statement.

• "Many of our members have announced additional measures in response to the Omicron variant, including strengthening testing, masking and other requirements, as well as encouraging booster vaccine doses for those eligible—and some cruise lines are requiring an additional test at embarkation," she added.

Go deeper: CDC: Avoid cruise ships regardless of COVID vaccination status

Editor's note: This story has been updated with new numbers from the CDC and comment from the Cruise Lines International Association.