Knowledge about the coronavirus and how it operates remains limited. But one thing we can feel sort of good about is the growing evidence that the illness is far more widespread than previously believed, just producing no symptoms in most of those who carry it.
Two recent studies back that theory. One of them, published in the medical journal Thorax, suggested that perhaps more than 80% of those who test positive may not have any clue that they’re carrying the virus.
Australian scientists looked at the spread of the virus on a cruise ship that departed from Argentina in mid-March. Among the 217 crew and passengers aboard, 128 contracted the virus. But within that subset, 104 people, or 81%, had no symptoms related to COVID-19. The authors of the study even said that they thought the number of infected patients was likely undercounted, meaning that perhaps even more were carrying the virus and not feeling any different from usual.
A separate study out of China looked at 78 patients who all tested positive for the virus. Among them, nearly half, 42%, exhibited no symptoms.
A study by Stanford University scientists last month tested 3,000 people in one city in California. Far more than expected had developed antibodies against the virus than had been expected, even though a relative lack of testing meant there had been few positive cases up to that point. If the antibodies were present in a person, that means he or she had been infected and recovered without ever being aware.
There are downsides to having no symptoms, of course. You could potentially develop them later. And asymptomatic people can inadvertently spread the virus, perhaps infecting those at higher risk of falling seriously ill.
But the fact that the virus may simply pass from person to person, leaving most or even just 40% unaware that they had contracted it, is a good thing. And the Centers for Disease Control and Prevention still estimates that 80% of people who experience symptoms will recover on their own.
The new data should further serve as an assurance that the virus is not deadly for the overwhelming majority of us. And it should further serve as public guidance for local government and health officials interested in opening up their economies at a quicker pace.
