More than 300 people fall ill on Ruby Princess cruise ship, CDC says

More than 300 passengers and crew members got sick on a recent sailing on Princess Cruises' Ruby Princess ship, the Centers for Disease Control and Prevention said.

The agency confirmed284 of the ship's 2,881 passengers reported being ill during its Feb. 26 voyage, along with 34 crew members, according to its website. The main symptomspassengers were experiencingwere vomiting and diarrhea.

"(Vessel Sanitation Program) epidemiologists and environmental health officers conducted a field response in Galveston, Texas, on March 5," the CDC said on its website.

While on board, they made "a targeted environmental health assessment to check for exposure and routes of illness transmission and monitored the ship’s outbreak prevention and response plan procedures," a CDC spokesperson said in an email. The outbreak investigation team is currently assessing their findings.

The cases were mild and likely caused by norovirus, a Princess spokesperson told USA TODAY in an emailed statement. The CDC said the causative agent is unknown, according to its website.

"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," the Princess spokesperson said.

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That sanitation program was developed in coordination with the CDC, according to the spokesperson, and includes steps like disinfecting high-touch surfaces such as railings and elevator buttons, isolating sick guests in their rooms until they are no longer contagious and giving "regular verbal and written communication to passengers about steps they can take to stay well while onboard."

Ruby Princess was also disinfected before its next sailing. The ship is currently on a week-long Western Caribbean voyage that will return to Galveston on March 12, the spokesperson said.

Norovirus cases have risen in the U.S. in recent months, but a CDC spokesperson told USA TODAY in February that the numbers remain in the expected range for this time of year.

Nathan Diller is a consumer travel reporter for USA TODAY based in Nashville. You can reach him at ndiller@usatoday.com.

This article originally appeared on USA TODAY: More than 300 guests and crew fall ill on Ruby Princess cruise ship