100 passengers and crew became ill on a cruise ship that returned to Fort Lauderdale on Friday, March 8.

The 100 people became ill during an 11-day Royal Caribbean International cruise that was scheduled to make port at St. Kitts, Barbados, Grenada and Aruba.

Spokeswoman Cynghia Martinez of the Miami-based cruise line announced that more than 100 guests and three crewmembers contracted a gastrointestinal illness that is believed to be a short-lived 'norovirus'. The ship carried 1991 passengers and 772 crew.

The source of the illness has not been confirmed.

Norovirus is transmitted by contaminated food or water, person-to-person contact and contamination of surfaces. Norovirus infection is characterized by nausea, vomiting, abdominal pain, loose stools and at times the loss of taste.  

The Centers for Disease Control and Prevention say that the contagious norovirus causes about 21 million illnesses in the United States yearly and contributes to approximately 800 deaths. It is rarely fatal, but those with weakened immune systems; the elderly; and the very young are particularly vulnerable to the virus.

The cruise ship passengers who became ill with what is believed to be norovirus were given over-the counter medication during the trip. Martinez said that the people responded well to the treatment.

Throughout the voyage, workers made extra effort in the cleaning regime to prevent further spreading of the virus.

The ship and cruise terminal were completely washed, scrubbed and sanitized after the trip ended at Port Everglades on Friday Morning, according to The Miami Herald.

The cruise ship left again on Friday afternoon as scheduled. Martinez stated that the cruise line was helping anyone who wasn't comfortable going on the ship's next voyage to reschedule.