BA.2 has an increased growth rate compared to BA.1 in all regions of England where there are sufficient cases present to make an assessment. Whilst growth rates can be overestimates early in the emergence of a variant, the apparent growth advantage is currently substantial.
Analysis from routine contact tracing data indicated higher secondary attack rates amongst contacts of BA.2 cases in households than those for contacts of other Omicron cases in the period 27 December 2021 to 11 January 2022. These secondary attack rates are not adjusted for vaccination status and reflect overall growth advantage rather than transmissibility.
