Because you need high throughput machine or it is a very slow manual process. Such machine like the FilmArray from Biomérieux or the GeneXpert from Cepheid will

Because you need high throughput machine or it is a very slow manual process. Such machine like the FilmArray from Biomérieux or the GeneXpert from Cepheid will only have their covid 19 add-on at the end of march, for the Cobas from Roche only now. When Korean had the homegrown Seegene one very quickly