Analysis of COVID-19 spread based on confirmed cases in Japan
A novel coronavirus occurred in Wuhan in 2019 and spread throughout the world. More than two years later, the virus is still mutating and causing infections around the world. The purpose of this work is to find out the spread mechanism of COVID-19 based on the cases in Japan. The effects of the measures to restrict social activity, such as lockdown, are estimated by using the broken-link model.