A new infectious disease caused by a novel coronavirus (COVID-19) has spread rapidly worldwide in 2020. The COVID-19 pandemic in Japan can be viewed as an urban disaster because transmission of this respiratory disease tends to occur in densely populated areas. A scientific understanding of the pathogen itself, the cause of the disaster (infectious disease), as well as infection control measures, are important to implement robust and appropriate countermeasures. This review discribes the features, especially the modes of transmission, of COVID-19 and the principles by which infection control is possible using one of the most effective infection control measures – personal protective equipment (PPE). Because COVID-19 is often transmitted to others by asymptomatic individuals through droplets, even those who are unaware of their infection should wear masks to prevent the spread of droplets that may contain the virus and effectively control the spread of disease. However, given the worldwide competition for masks and the urgent requirement of effective controls, it is necessary to conduct further research to establish a system that can supply adequate numbers of masks to regions where many people are infected in the country, with no shortage of masks, in order to make the country more resilient to disasters caused by infectious diseases in the future.

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