Cruises are back — and so are stomach viruses, diarrhea, and vomiting onboard

• 11 sick bug outbreaks have been reported on cruises so far this year.
• That's the same as the number reported in the whole of 2018.

Cruises are back up to pre-pandemic levels — and so are onboard stomach bug outbreaks.

Holland America's the Nieuw Amsterdam, which set sail on May 6, is among a string of 11 cruise ships to report gastrointestinal illness onboard this year, according to the Centers for Disease Control and Prevention. 213, or over 10%, of passengers and 35, or 4%, of crew on the Nieuw Amsterdam have been reported sick during the voyage that lasts until May 21, mostly with diarrhea and vomiting.

The same number of sick bug outbreaks on cruise ships have been reported so far this year than in the entirety of both 2017 and 2018, when there were 11 in total. 10 outbreaks were reported in 2019 and 13 in 2016.

Of the 11 outbreaks this year, four were caused by highly contagious norovirus. Holland America told The Washington Post it suspects that's the cause of its outbreak, too.

"The cases have been mostly mild and quickly resolving," the statement read.

Like other affected cruise ships, Holland America told the CDC it has increased cleaning and disinfection procedures to deal with the outbreak and has sent stool samples to a lab to determine the cause.

The cruise industry shut down during the pandemic, and as such there were no outbreaks of gastrointestinal illness reported in 2020, and one in 2021 as trips started up again.

In 2022 there were still only four outbreaks, which the CDC told The Washington Post was likely due to fewer passengers on ships during that time, as well as an increase in cleaning, disinfection, and the number of hand sanitizer stations, along with crew-served buffets, and physical distancing — all as a result of the pandemic.

In a statement to The Washington Post, the Cruise Lines International Association said that gastrointestinal illness outbreaks on cruise ships are "quite rare" compared to those on land.

It added that alongside the crew, passengers should be doing all they can to keep themselves, their families, and fellow travelers healthy.

To stay healthy while cruising, the CDC recommends: washing your hands often to prevent the spread of germs, getting plenty of rest, drinking enough water. If you see someone who is sick with vomiting or diarrhea, leave the area and report it to staff.

Insider has contacted the CDC and Holland America for comment.