New Delhi: A new study has assessed cruise ship passengers under isolation during the current pandemic and found that the prevalence of ‘silent’ symptomless COVID-19 infection may be much higher than thought.
Researchers, including those from Macquarie University in Australia, noted that the study offers the first analysis of complete COVID-19 testing of all passengers and crew on an isolated cruise ship during the COVID-19 pandemic.
According to the findings, published in the journal Thorax, more than four out of five of passengers and crew who tested positive for the infection had no symptoms.
Based on the results, the scientists believe that the prevalence of COVID-19 on affected cruise ships is likely to be significantly underestimated.
They said strategies are needed to assess and monitor all passengers to prevent community transmission after disembarkation.
The researchers also noted that there is a pressing need for accurate global data on how many people have been infected so far.
In the current study, they assessed the COVID-19 test results of 217 passengers and crew aboard an expedition cruise ship which departed from Ushuaia, Argentina, for a planned 21 day cruise of the Antarctic.
The scientists said the ship set sail in mid-March after the World Health Organization (WHO) had declared COVID-19 a global pandemic.
They said people who in the previous three weeks had passed through countries where COVID-19 infection rates were already high, were not allowed to board, adding that everyone’s temperature was taken before embarkation.
To reduce chances of the passengers contracting the virus, the researchers said, hand sanitising stations were plentiful aboard the ship, particularly in the dining room.
However, of the 217 passengers and crew on board, 128 tested positive for COVID-19, the study noted.
Nearly a fifth of those who tested positive were symptomatic, the scientists said, adding that more than 6 per cent of the 128 passengers required medical evacuation.
They said about 3 per cent of those who showed symptoms were intubated and ventilated, and one person died.
One of the most important findings of the study, the researchers said was that the majority of COVID-19-positive patients, about 80 per cent, did not exhibit any symptoms. The first case of fever, according to the study, was reported on day 8, prompting the immediate adoption of infection control measures.
