According to a study in Denmark, Omicron subvariant BA.2 was found to be tied to higher likelihood of infection among households, irrespective of vaccination status, compared to the original BA.1 variant.

In comparison with BA.1, BA.2 was tied to more than double the odds of infection among unvaccinated people (OR 2.19), vaccinated individuals (OR 2.45), and those who had received a booster shot (OR 2.99), noted Frederik Plesner Lyngse of University of Copenhagen, and colleagues. Additionally, unvaccinated primary cases in households with BA.2 infection were linked with over two-fold higher odds of transmission (OR 2.62), in comparison with BA.1 households. 

It was noted that the transmissibility was lower in both BA.1 and BA.2 households if the primary case was vaccinated, with or without a booster shot. The findings are posted as preprint on medRxiv… (Medpage Today)