Twitter Discussions and evaluations about the delta variant of COVID-19 in Japan

The delta variant is one mutant of COVID-19, which is more transmissible than pre-existing variants of SARS-CoV-2. The Japanese government failed to curve the explosive rise of the infection, and therefore the healthcare system was on the verge of a crisis. This research aims to examine what people think and feel about this situation by using tweets on Twitter. 3,339,002tweets related to terms of Indian variant or delta variant or lambda virus were collected from May 9, 2021, to August 25, 2021. Tweets including terms of virus, infection, vaccine, symptoms have gradually increased. The peak of tweets of fear and anger was early July 2021. Tweets of medical resources and politics & governments surged in August 2021. The fear, anger, and antipathy to the attitude of the Japanese government were observed on Twitter. © 2021 ACM.