Global Mass Gathering during Pandemic:
Interim Overview of COVID-19 countermeasures during the Tokyo 2020 Olympic and Paralympic Games

Over the past 20 years, Japan held various international mass gathering events or high visibility events where VIPs from various countries participated. According to the WHO, a mass gathering event is defined as “a planned or spontaneous event where the number of people attending could strain the planning and response resources of the community or country hosting the event.” For planned mass gatherings, adequate preparation is required to ensure that the event is safe and does not compromise the planning and response resources of the country or community. In the context of global efforts to improve health security, preparation for mass gathering events is emphasized as an opportunity to improve the capacity to deal with public health crises. Therefore, documenting and delivering lessons related to the preparedness and response in conducting such events is crucial. Our research group on health security for mass gatherings/high profile events was launched in 2019 and was funded by the Ministry of Health, Labour and Welfare (MHLW) of Japan with the abovementioned objective.
Following the decision in September 2013 to host the 2020 Olympic and Paralympic Games in Tokyo was finalized, various preparations have been made in the area of public health. Public health measures were mainly focused on managing heatstroke, natural disasters, imported infectious diseases, and terrorism. However, the global situation drastically changed after the outbreak of COVID-19 at the end of 2019, just before the event, which soon progressed to a pandemic. As a result, the event was postponed for 1 year, and the implementation of countermeasures against COVID-19 during the Tokyo 2020 Games became the most critical concern. In addition, the emergence of more infectious and transmissible variants made the planning even more difficult. The number of COVID-19 cases in Tokyo increased just before the event; and thereafter, the Games were held while the country was under a state of emergency. Although it was an extremely challenging situation to hold such an international mass gathering event under a pandemic, and the time for preparation was limited, countermeasures were developed to ensure the safety of all participants to deal with the evolving situation.
This report aimed to provide a comprehensive overview of the series of public health efforts made to implement the COVID-19 countermeasures during the Tokyo 2020 Games. It is our sincere hope that this report will be useful for developing future public health measures for mass gatherings and social activities under the COVID-19 epidemic, both in Japan and worldwide.

SAITO Tomoya, MD, MPH, PhD
Principal Investigator
MHLW Health Science Research Group
on Health Security for Mass Gatherings/High Profile Events
Center for Emergency Preparedness and Response
National Institute of Infectious Diseases, JAPAN