The U.S. Centers for Disease Control and Prevention report an outbreak of norovirus on a cruise ship in Alaska.

KTOO public media reports 73 people have reported getting sick on the Holland America cruise ship Zaandam.

The ship, which is carrying more than 2,000 passengers and crew, was in Juneau on Friday. The ship is expected to make additional stops in Alaska before returning to Seattle on July 2.

Norovirus is highly contagious and can cause vomiting and diarrhea usually a day or two after exposure. Most people fully recover within a few days.

The U.S. Forest Service monitors reports of outbreaks on cruise ships so it can take steps to bolster sanitation.