Nearly 90 people onboard a Holland America cruise ship that departed from Fort Lauderdale at the end of December suffered from gastrointestinal illnesses due to a norvovirus outbreak, according to the Centers for Disease Control and Prevention.

The Rotterdam departed from Fort Lauderdale on Dec. 28 and returned on Friday, and dozens of people, including both passengers and crew members, were reported to be sick.

In total, 81 passengers and 8 crew members were reported to be sick.

In response to the norovirus outbreak, Holland America Cruise Line and the crew onboard the ship increased cleaning and disinfection procedures according to the outbreak prevention and response plan, the CDC reported.

In addition, stool samples from those suffering from the gastrointestinal illnesses were taken for testing.

Passengers and crew member that were sick were also isolated from everyone else, the CDC said.

Officials said that the predominant symptoms that were reported included vomiting and diarrhea.

Cruise ships are required to report cases to CDC

The CDC said that gastrointestinal illness is a commonly used term for acute gastroenteritis (AGE), and reporting gastrointestinal illness is important.

The CDC said that when passengers and crew inform medical staff onboard of their symptoms, it will help outbreaks get detected quickly.

That will then allow steps to be taken to limit the spread of the illness onboard the ship.

Medical staff evaluate the symptoms to see if they meet the CDC's definition for AGE.

That included three or more loose stools within a 24-hour period, or what is more than normal for that specific person, or vomiting with one of the following symptoms – diarrhea, muscle aches, headaches, abdominal cramps or a fever.

Cruise ships are also required to report the cases to the CDC.