Right. In fact the fact that many could have it with no symptoms means the mortality rate will always be in question.
A Person Can Carry And Transmit COVID-19 Without Showing Symptoms, Scientists Confirm
ARIA BENDIX, BUSINESS INSIDER 24 FEB 2020
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Chinese health officials previously estimated that the incubation period for the virus ranged from one to 14 days, but recent research suggests it could be as long as 24 days.