Omicron Subvariants: AOmicron Subvariants: ANew Challengepast infections and vaccines.New variants threaten immunity fromImmunologyOmicron Subvariants and Their Immunity ChallengesNew Omicron subvariants complicate immune responses from past infections and vaccinations.2025-08-28T18:02:48+00:00 ― 4 min read