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How Dangerous Are Covid-19 Silent Spreaders?
A lot of people without symptoms are spreading the coronavirus, a new study suggests
Before boarding for a mid-March cruise from Argentina to Antarctica, passengers were screened for fever. In addition, any prospective passenger who had been to an area with Covid-19 outbreaks was not allowed to board.
“We thought we were pretty safe,” says Alvin Ing, MD, a professor of respiratory medicine at Macquirie University Hospital in Australia and one of several scientists on the cruise. “However, reality struck on the eighth day, when a passenger developed fever, and it sort of snowballed from there.”
Passengers were then confined to their cabins. The crew donned protective equipment and ended all but essential services to reduce crew-passenger contact (they still delivered meals).
Yet by the 20th day of the aborted cruise, before the 217 passengers and crew had any contact with people beyond the ship, 59% tested positive for coronavirus. Among them, 81% had no symptoms, Ing and his colleagues report in the journal Thorax.
Infections ‘much higher’ than expected
The finding illustrates not just how quickly Covid-19 can spread, but also the importance of testing and…
