Study doesn't seem to check for the B.1351 (SA) variant which has shown a limited ability to overcome natural immunity. Arguably this variant isn't a big deal

Study doesn't seem to check for the B.1351 (SA) variant which has shown a limited ability to overcome natural immunity. Arguably this variant isn't a big deal for now (compared to spreading out vaccine doses), but I suspect previously infected individuals will need to get a single shot eventually.