Apollo's Arrow: The Profound and Enduring Impact of Coronavirus on the Way We Live

by Nicholas A. Christakis MD PhD

The time between when a person is infected and when he or she shows signs or symptoms is called the incubation period. This ranges from two to fourteen days in SARS-2 (hence the recommended fourteen days of isolation) and is typically about six to seven days. For SARS-1, the incubation period was shorter, ranging from two to seven days. But there is another important interval, the latent period, which is the time between when a person is infected and when he or she becomes infectious—that is, able to spread the disease to others. The incubation period and the latent period are not always the same. The latent period is often shorter than the incubation period in SARS-2, but that was generally not the case in SARS-1. The difference between the latent period and the incubation period is sometimes known as the mismatch period; it’s calculated by measuring the incubation period and subtracting the latent period.