One reason why the CDC likely isn’t fully considering these studies yet is that they are not peer-reviewed right now. Medrxiv is a pre-press publication. Medrxiv warns readers, “Caution: Preprints are preliminary reports of work that have not been certified by peer review. They should not be relied on to guide clinical practice or health-related behavior and should not be reported in news media as established information.” https://www.medrxiv.org/