Given that serial interval is a very effective way to amplify an already-high R0 to great evolutionary advantage, and common colds/flu etc all have developed serial interval of more like 1-2 days showing there’s plenty of room for COVID to climb in this regard, I would expect lots of new dominant strains to show shortened serial interval regardless of heritage.
Not sure if there’s publication bias or measurement bias here but the first link on google shows a study estimating Omicron serial interval at 2.2 days in South Korea.
Given that serial interval is a very effective way to amplify an already-high R0 to great evolutionary advantage, and common colds/flu etc all have developed serial interval of more like 1-2 days showing there’s plenty of room for COVID to climb in this regard, I would expect lots of new dominant strains to show shortened serial interval regardless of heritage.
Not sure if there’s publication bias or measurement bias here but the first link on google shows a study estimating Omicron serial interval at 2.2 days in South Korea.