The monitoring concentration of viruses in sewage can grasp the pandemic of infectious diseases in the catchment area. This study aimed to clarify the effects of COVID-19 predicted number as wastewater-based epidemiological information on the changes of going out behavior. We conducted a questionnaire survey for Sendai citizens and analyzed by covariance structure model about two groups. Group A respondents received information "COVID-19 predicted number is 12,000 people next 1 week in Sendai city", group B respondents received "1,200".

 As a result, there was no significant relationship between the changes of going out behavior and the experience of COVID-19 infection or the number of vaccination doses. In group B, people who had high-level risk perceptions and who were anxious about going out tended to implement new measures and increase the frequency of their measures during going out.