LAUSR

Key Points Question Would investigation of asymptomatic SARS-CoV-2 add to the understanding of the state of infection in the community and population of Japan by complementing available data on symptomatic infections? Findings In this cross-sectional study of 1 million individuals in Japan with asymptomatic SARS-CoV-2 infection, the prevalence of infection was generally lower than in similar studies from other nations. An inverse association between vaccination rate and age group for asymptomatic infections and symptomatic patients was seen, with younger age groups with lower vaccination rates including more symptomatic patients and asymptomatic infections. Meaning The findings of this cross-sectional study suggest that Japan had a low rate of SARS-CoV-2 infection in the general population compared with other countries.