A new cruise ship study suggests that the number of people who are infected with the new coronavirus but have no symptoms may be much higher than believed. More than 80% of those who tested positive for the infection had no symptoms, according to the study published online May 27 in the journal Thorax.
The findings could be important as lockdown restrictions begin to be eased, and they highlight the need for accurate data on how many people worldwide have been infected, journal joint editor-in-chief Alan Smyth said in a linked blog.
The study focused on a ship with 128 passengers and 95 crew that left Argentina in mid-March for a planned 21-day cruise of the Antarctic. The voyage began after the World Health Organization (WHO) had declared the new coronavirus a global pandemic.
Passengers who in the previous three weeks had been in countries where coronavirus infection rates were high were not allowed to board. All passengers who were allowed to board had their temperature taken before embarkation, and the ship had numerous hand sanitizing stations, particularly in the dining room.
After the first case of fever was reported on day 8 of the voyage, infection control measures were immediately implemented, including confining passengers to their cabins and the use of personal protective equipment by any crew member in contact with sick passengers. The ship arrived in Uruguay on day 13, where eight passengers and crew eventually required medical evacuation to hospital for COVID-19-related respiratory failure.
