Omicron sub-variant BA.2 variant better than BA.1 at infecting booster vaccinated: Experts

“If you have been exposed to Omicron BA.2 in your household, you have 39% probability of being infected within seven days. If you instead had been exposed to BA.1, the probability is 29%,” lead study author Frederik Plesner told Reuters adding that, which means BA.2 is around 33% more infectious than BA.1

So far, BA.2 cases have been registered from over 54 countries including India, United States, Britain, Sweden and Norway, but to a much lesser extent than in Denmark.

BA.2 was relatively better than BA.1 at infecting vaccinated and booster-vaccinated people, indicating greater “immune evasive properties” of the subvariant, the study shows

But vaccines still played an important role, the study underlined, since both booster-vaccinated and fully vaccinated individuals were less like to get infected and transmit either subvariants, compared to those not vaccinated.

Preliminary analysis by SSI has shown that there is no difference in the risk of hospitalisation for BA.2 compared to BA.1.

More than 18,000 genetic sequences of BA.2 have been uploaded to GISAID, a global platform for sharing coronavirus data, according to data collected by Scripps Research labs. The strain has been detected in at least 54 countries.

“Thus far, we haven’t seen it start to gain ground” in the US, said Dr Wesley Long, a pathologist at Houston Methodist in Texas, which identified three cases as of earlier this week.