Before revision:  ( 3  ) Although the number of reported cases is lower than the actual number of cases, a high spatial correlation exists between the cumulatively reported cases and the actual situation.
After revision:  ( 3 ) The impact of under-reporting cases on the early stages of the pandemic is greater than that on its later stages, and the impact on the early onset area is greater than that on the late onset area. (4 ) Although the number of reported cases is lower than the actual number of cases, a high spatial correlation exists between the cumulatively reported cases and the actual situation.