Original Antigenic Sin. See here: https://pubmed.ncbi.nlm.nih.gov/28479213/ https://pubmed.ncbi.nlm.nih.gov/28479213/ Here's also some analysis about this eff

Original Antigenic Sin. See here: https://pubmed.ncbi.nlm.nih.gov/28479213/ https://pubmed.ncbi.nlm.nih.gov/28479213/ Here's also some analysis about this effect with Omicron, which seems honest about the limitations: https://boriquagato.substack.com/p/theres-something-antigenic-in-denmark https://boriquagato.substack.com/p/theres-something-antigeni...