biostudies-literatureUnknown28(8)Kremer CWe investigated the serial interval for SARS-CoV-2 Omicron BA.1 and Delta variants and observed a shorter serial interval for Omicron, suggesting faster transmission. Results indicate a relationship between empirical serial interval and vaccination status for both variants. Further assessment of the causes and extent of Omicron dominance over Delta is warranted.Emerging infectious diseases1699-1702https://www.ebi.ac.uk/biostudies/studies/S-EPMC9328897biostudies-literatureSerial Intervals for SARS-CoV-2 Omicron and Delta Variants, Belgium, November 19-December 31, 2021.PMC9328897Torneri ABraeye TKremer CProesmans KAndre EHens NfalseSerial Intervals for SARS-CoV-2 Omicron and Delta Variants, Belgium, November 19-December 31, 2021.We investigated the serial interval for SARS-CoV-2 Omicron BA.1 and Delta variants and observed a shorter serial interval for Omicron, suggesting faster transmission. Results indicate a relationship between empirical serial interval and vaccination status for both variants. Further assessment of the causes and extent of Omicron dominance over Delta is warranted.2022-01-01T00:00:00Z2022 Aug2025-06-01T03:53:52.512Z2025-06-01T03:53:52.512ZS-EPMC93288973573219510.3201/eid2808.220220