For the seventh time in 2015, the Centers for Disease Control and Prevention’s (CDC) Vessel Sanitation Program (VSP) is investigating an outbreak on board a cruise line vessel.

Holland America Line ms Maasdam/Julien Bertrand
Holland America Line ms Maasdam/Julien Bertrand

Holland America Line’s ms Maasdam returned to Ft. Lauderdale on May 1, 2015 after a two-week voyage, but not after dozensof passengers and crews were stricken with symptoms of vomiting and diarrhea.

According to official numbers Friday, 67 of  the 1,138 passengers on board (nearly 6%) and 12 of the 578 crew members (2%) became ill. To date, the etiology of the outbreak is still unknown.

In response to the outbreak, Holland America Line and the crew aboard the ship are taking the following actions: Increasing cleaning and disinfection procedures according to their outbreak prevention and response plan, making announcements to notify on board passengers of the outbreak, encourage case reporting, and encourage hand hygiene and collected stool specimens from ill passengers and crew.

This is the seventh cruise line outbreak of the year. Last week, a norovirus outbreak was reported on board Princess Cruises’ Coral Princess.

The VSP provides assistance to cruise ships when the number of ill passengers or crew members reaches 2% or more of the total number of passengers or crew members or when an unusual GI illness pattern or characteristic is found.