COVID-19 as we know will cease to exist by 2022. 我们知道，新冠会在2022年以前消失。
COVID-19 as we know it will cease to exist by 2022. 我们所认识的新冠会在2022年以前消失。

删掉something.
as we know (it) 用烂了，习语化了，你硬抠语法很误导自己。
你先给我我明白，that's it. 的语法，我再告诉你know句

The context is that what we know stands for or refers to all the information we've collected since the life' start (before the birth). You may pick something from it consciously, but in most of the cases such a manner would consume much longer time than it is.