It is too early to tell for now. Delta is less than 10% of cases in the US according to the CDC data tracker. I looked all over for relevant studies and data.

It is too early to tell for now. Delta is less than 10% of cases in the US according to the CDC data tracker. I looked all over for relevant studies and data. There is only one publicly available source on that distinction, anywhere. It's by Raoult's Institut Infection Mediterranee in Marseilles, in France. I suggest their Youtube channel (warning:it's in French) They are the only one systematically sequencing everybody they care for (40'000 + patients to date, the largest series worldwide). However, even they say they do not have enough data either way to make any pronouncement, at least before a month or two.