I have been trying to find info (maybe someone can) on the sudden disappearance of the Wuhan, Alpha, Beta, Gamma variants. On most graphs they are down to < 2%. Vaccines pretty march started at the beginning of the year so it wasn't the vaccines that kicked them out. Did the Delta variant just push them aside. Don't know. Possibly they ran their course. i.e. The infection-spread and dissipation is done. Did they all reach herd immunity mainly in other parts of the world due to our international border closed. That took about 15 months say. In that case add 15 months to the Delta (March) = June 2022. By then the Delta will be < 2%. With the help of vaccines it should be quicker and quicker still the sooner you end lockdowns. Stacks of epidemiologists on tv though I would like them to answer this query. Or maybe the fantastic health advice department.