The mutations make it more transmissible. https://scholar.google.com/scholar?hl=en&as_sdt=0%2C6&q=B.1.617&btnG=#d=gs_qabs&u=%23p%3DzPBqQzAlNs0J
The mutations make it more transmissible. https://scholar.google.com/scholar?hl=en&as_sdt=0%2C6&q=B.1.617&btnG=#d=gs_qabs&u=%23p%3DzPBqQzAlNs0J