Is the incubation period of coronavirus COVID-19 longer than initially assumed, and ranging up to 27 days or longer?

This is true and in fact, in some individuals, the virus persists even though they are asymptomatic, so this will produce carriers and this is a particularly knotty problem because they become like a "Typhoid Mary" who will continue to disseminate the virus as they move about and will not be discovered unless each and every person is tested rigorously.