Before revision:  The results show that (1) the lognormal distribution was the most suitable to describe the evolution of epidemic with time; (2) the estimated peak infection time of the  reported cases lagged the peak infection time of the healthcare worker cases , and the estimated infection time interval of the reported cases was smaller than that of the healthcare worker cases.
After revision:  The results show that the reported cases lagged the peak infection time of the healthcare worker cases , and the estimated infection time interval of the reported cases was smaller than that of the healthcare worker cases.