A city hospital, located in the prefecture where the number of COVID-19 patients was the second largest in Japan, admitted 25 COVID-19 patients in the period in which the daily number of infected individuals reached a peak in Japan. We consider that analysis of the patients’ backgrounds, symptoms, and outcomes may contribute to the preparations for the second wave of infection. We, therefore, retrospectively reviewed the information obtained from an electronic medical record system and found that about one-third of these COVID-19 patients were not residents of the city, and that the use of ICT is necessary for communication and coordination with organizations including the public health centers. In addition, some COVID-19 patients presented with diarrhea and smell/taste disorders in addition to respiratory symptoms. Also, while the potential for clinical deterioration is low, precautions against such deterioration are necessary in individuals who have had close contact with severely ill patients.