Out of the 2,881 passengers on the cruise, the CDCshared in a news release, 284 became ill, along with 34 of its 1,159 crew members. Vessel Sanitation Program epidemiologists and environmental health officers conducted a field response on Sunday after it docked in Galveston, Texas.

After their initial investigation, predominant symptoms among the ill were discovered to include vomiting and diarrhea.

While it is unknown when the first case was reported, the CDC shared that the voyage began on Feb. 26 and that the cases that have been reported account for the entire cruise trip.

“At the first sign of an increase in the numbers of passengers reporting to the medical center with gastrointestinal illness, we immediately initiated additional enhanced sanitization procedures to interrupt the person-to-person spread of this virus,” a representative from Princess Cruises, the company that operates the ship, tells PEOPLE in a statement.

Mark Metcalfe/Getty

WOLLONGONG, AUSTRALIA - APRIL 23: The Ruby Princess cruise ship departs from Port Kembla on April 23, 2020 in Wollongong, Australia. Australian Border Force has ordered the Ruby Princess to depart Australian waters today, as two separate inquiries continue over how the ship’s 2700 passengers were allowed to disembark in Sydney in March without adequate health checks during the coronavirus (COVID-19) pandemic. A special commission of inquiry has been established by the NSW government over the handling of the Ruby Princess' arrival into Sydney on 19 March, while NSW Police are also conducting a separate criminal investigation. There are now 21 deaths linked to the Ruby Princess along with more than 600 confirmed coronavirus (COVID-19) cases. (Photo by Mark Metcalfe/Getty Images)

An investigation has begun into the cause behind the outbreak, along with preliminary response measures that include the collection of stool samples from the sickened passengers and crew members for pathogenic examination.

In response to the outbreak, the Princess Cruises representative adds that the company disinfected high-touch surfaces like railings, door handles, and elevator buttons and encouraged sickened passengers to isolate in their cabins.

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The CDCshares on its websitethat “norovirus is a very contagious virus that causes vomiting and diarrhea.”

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“As an additional precaution, the ship underwent an additional disinfection on March 5 in Galveston ahead of its next departure,” Princess Cruises adds in their statement to PEOPLE. “The ship is now on a seven-day western Caribbean cruise, returning to Galveston on March 12.”

Ingrid Vasquez

source: people.com