Just over 300 people have been sickened in norovirus outbreaks on three different cruise ships in December, new government data shows.
This is the only month this year in which the U.S. Centers for Disease Control and Prevention has reported three confirmed norovirus outbreaks on cruise ships.
In all, 301 passengers and crew members fell ill during the December outbreaks, health officials said.
"Norovirus can be especially challenging to control on cruise ships because of the close living quarters, shared dining areas and rapid turnover of passengers," according to the CDC. "When the ship docks, norovirus can be brought on board in contaminated food or water; or by passengers who were infected while ashore."
Those sickened on Princess Cruises' Ruby Princess, on a trip around Hawaii's island, and Holland America's Rotterdam and Zuiderdam voyages, both in the Caribbean, mostly experienced diarrhea and vomiting.
The latest outbreak was reported on Holland America's Rotterdam ship, which is set to end its Caribbean trip Friday in Fort Lauderdale.
CDC officials said 83 of the 2,192 passengers on board and 12 of the 953 crew members were sickened.
"At Holland America Line, the safety and well-being of our guests and crew is our top priority. During the current voyage, a number of guests on Rotterdam reported symptoms of gastrointestinal illness," a Holland America spokesperson told CBS News. "The cases have mostly been mild and quickly resolving."
In response to the outbreak, there was additional cleaning and disinfection, and sick passengers and crew members were isolated.
Once the Rotterdam ship arrives in Fort Lauderdale, it will undergo a comprehensive sanitization process before its next trip, the cruise line told CBS News.
But that was just one of three norovirus outbreaks on ships this month.
There was also a norovirus outbreak on Holland America's Zuiderdam voyage earlier this month. Over the course of that Dec. 4-11 voyage, 87 out of 1,923 passengers were reported ill, in addition to four of the 757 crew members.
Princess Cruises also dealt with a norovirus outbreak this month on its Ruby Princess ship during a cruise that started in San Francisco on Dec. 2, cruised around Hawaii and ended on Wednesday.
In total, 103 of 3,001 passengers and 12 of 1,142 crew members onboard reported being ill.
Princess Cruises did not respond to CBS News' request for comment.
There are about 2,500 reported norovirus outbreaks in the United States each year.
Norovirus, often coined the "cruise ship virus," causes more than 90% of diarrheal disease outbreaks on cruise ships, according to the CDC. Still, norovirus outbreaks on cruise ships account for only a small percentage of all reported norovirus outbreaks.
More information
The CDC has more on norovirus.
SOURCE: U.S. Centers for Disease Control and Prevention, data, Dec. 20, 2024; CBS News