**7. Limitations of this research and prospects**

The limits of this study are described.

First, the number of responses from local governments that actually opened shelters under COVID-19 is small. At the time of the survey, the period during which a natural disaster could occur under COVID-19 was about half a year, and few local governments opened shelters there. As the number of cases increases, it is possible that the overall trend will change, and new issues will become apparent.

Second, the scale of the disaster targeted was small. This is fortunate, but the scale of the disaster and the lengthening of the shelter opening period could lead to events different from those revealed in this survey.

In the future, based on the results of this research, we would like to deepen our studies on countermeasures for complex disasters of natural disasters and COVID-19, especially shelter management.
