The longer a virus can replicate inside a person before causing symptoms, the harder it can be to stop — because of the greater potential for the infected to unknowingly spread it far and wide.
Among COVID-19’s pernicious features, its incubation period is longer than many other respiratory viral infections, including influenza, respiratory syncytial virus and rhinovirus.
The good news is that the interval between exposure to the coronavirus and the development of COVID-19 symptoms appears to be narrowing.