The CDC Says Now is Not The Time to Take a Cruise

During the initial stages of the pandemic, cruise ships were a major concern for disease transmission.

On Feb. 20, the World Health Organization (WHO) announced that more than 50 percent of the known COVID-19 cases in the world, apart from China, could be traced to one cruise ship, the Diamond Princess.

The ship was quarantined in Japan with more than 3,700 people onboard. Hundreds had become sick with COVID-19.

“Asymptomatic spread of the virus among passengers contributed to the significant morbidity and mortality,” Glatter said.

“Cruise ships are often referred to as ‘floating petri dishes,’ recognizing their high potential for rapid spread of infectious diseases — particularly the norovirus, but COVID-19 of late,” he said.

In March, more than 800 COVID-19 cases were linked to three different cruise ship voyages, according to the CDC.

“Even pre-COVID, we learned that cruise ships are ideal incubators for infectious diseases like E. coli, norovirus, chickenpox, and the flu,” said Dr. Shirin Peters, founder of Bethany Medical Clinic in New York.

“The risk of infection is amplified on a cruise ship because of close quarters of the passengers, and passengers really being at the mercy of the hygiene protocols of the company running the cruise lines,” she said.

Additionally, people can transmit the coronavirus even when they don’t have symptoms. Approximately 40 percent of coronavirus infections occur asymptomatically or before symptoms appear, so containing the spread of the virus onboard is challenging.

The modes of COVID-19 transmission make it difficult to not only detect but challenging to enforce isolation and quarantine protocols in an environment where physical distancing is difficult.

“It’s vital to understand that the difficulty of detecting spread of infection among crew members on a ship may consequently allow the virus to continue spreading among passengers and crew alike during sequential voyages,” Glatter said.

“We also have realized that COVID-19 can spread from ship to ship as a result of crew from a ship with an outbreak transferring to other ships for additional trips. This can facilitate rapid spread from country to country,” he said.