The term quarantine, quantitatively refers to 40 days, but currently isolation for 14 days is accepted worldwide. According to the dynamics of the infection, would it be more convenient to adjust the isolation measures for 40 days? 

According to Health24 news, Researchers say the average incubation period for the Covid-19 period is about five days, confirming that the 14-day quarantine period being used by most health authorities cross the globe is “appropriate”.

Link: https://www.health24.com/Medical/Infectious-diseases/Coronavirus/coronavirus-why-the-14-day-quarantine-period-20200311-3