In May, Princess Cruises’ Star Princess reported a norovirus outbreak on board the ship that affected some 151 passengers and crew. Now the vessel is docked in Vancouver after a end of a 15-day Hawaiian voyage with some 61 people sickened.

“We saw an increase in guests with gastrointestinal illness on the previous voyage,” confirmed a spokesperson with Princess Cruises.

“As a result, we’re conducting enhanced cleaning today in Vancouver, delaying embarkation for the next cruise to 5:30 p.m. this evening.”

CBC News reported at least two passengers were transported by ambulance from the dock to hospital, in stable condition.

Since only 2.3 percent of the passengers were affected (of the 2,590 total passengers on the voyage), special protocol and disinfection of a vessel was not required.

Norovirus is a very contagious virus. You can get norovirus from an infected person, from contaminated food or water, or by touching contaminated surfaces. The virus causes your stomach or intestines or both to get inflamed (acute gastroenteritis). This leads you to have stomach pain, nausea, and diarrhea and to throw up.

Why are noroviruses associated with cruise ships? According to the CDC, health officials track illness on cruise ships. So outbreaks are found and reported more quickly on a cruise ship than on land; close living quarters may increase the amount of group contact and people joining the ship may bring the virus to other passengers and crew.