What is norovirus? Alaska cruise ship hit with third gastrointestinal outbreak in two months

An Alaska cruise ship has been struck by its third gastrointestinal illness outbreak in just two months, with nearly 20 passengers falling ill during the latest voyage.

Sixteen passengers out of the total number of sixty-two passengers on board the National Geographic Sea Bird, which was chartered by Lindblad Expeditions, were suffering from gastrointestinal illness while sailing through Alaska on July 10.

The CDC’s Vessel Sanitation Program reported this latest outbreak on July 12, marking the ship’s third Gl illness outbreak since May.

Earlier, the outbreak was reported on May 28 and June 28, confirmed as norovirus. It is a highly contagious vomiting bug that spreads through contaminated food, water, surfaces, and close contact.

The cause of the outbreak is stated as “unknown,” although according to the CDC, norovirus is typically the cause of an outbreak on cruise ships, and it can sometimes take time to find out the cause.

As part of its outbreak prevention protocol, Lindblad Expeditions has taken steps to clean and disinfect more thoroughly, while the crew has quarantined those who are ill and contacted the CDC on how to report the cases and collect samples from the patients.

The CDC is monitoring the outbreak from a remote location.

In 2026, the CDC logged eight gastrointestinal outbreaks on cruises that met its threshold for public notification. Among them, five were caused by norovirus, while two were linked to E.coli.