Predicted domination of variant Delta of SARS-CoV-2 before Tokyo Olympic games, Japan | medRxiv

Predicted domination of variant Delta of SARS-CoV-2 before Tokyo Olympic games, Japan | medRxiv: Using nucleotide sequences of SARS-CoV-2 strains collected in Japan, the relative instantaneous reproduction numbers of the R.1, Alpha, and Delta variants with respect to other strains circulation in Japan were estimated at 1.256, 1.449, and 1.776, respectively. The numbers can range 1.198–1.335 for R.1, 1.342–1.596 for Alpha, and 1.557–2.00 for Delta depending on the assumed serial interval distributions. The frequency of the Delta is expected to take over the Alpha in Japan around July 12, 2021. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This work was supported by the Japan Agency for Medical Research and Development (grant numbers JP20fk0108535). K.I. received funding JSPS KAKENHI (21H03490). P.C. was supported by the World-leading Innovative and Smart Education Program (1801) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan. H.N. received funding from Health and Labor Sciences Research Grants (20CA2024 and 20HA2007); the Japan Agency for Medical Research and Development (JP20fk0108140); JSPS KAKENHI (21H03198) and the Japan Science and Technology Agency (JST) SICORP (e-ASIA) program