MOBILE, Ala. --Cruise ships are often the perfect setting for outbreaks of infectious diseases because of their closed environment and contact between travelers from many different areas around the world.
According to the CDC’S morbidity and mortality weekly report, more than 800 cases of laboratory-confirmed COVID-19 cases occurred during outbreaks on three cruise ship voyages, and cases linked to several additional cruises have been reported across the United States.
During the beginning stages of the COVID-19 pandemic, the Diamond Princess was the setting of the largest outbreak outside mainland China. Among 3,711 Diamond Princess passengers and crew, 712 had positive test results for SARS-CoV-2 (the virus that carries the coronavirus disease). Of these, 331 were asymptomatic at the time of testing. Among 381 symptomatic patients, 37 required intensive care, and nine died. Infections also occurred among three Japanese responders, including one nurse, one quarantine officer, and one administrative officer.
According to the CDC, the Diamond Princess outbreak suggests that 17.9% of infected persons never developed symptoms. A high number of asymptomatic infections could partially explain the high attack rate among cruise ship passengers and crew.
SARS-CoV-2 RNA was found on a wide range of surfaces in cabins of both symptomatic and asymptomatic infected passengers up to 17 days after cabins were vacated on the Diamond Princess but before disinfection procedures.