Chennai: The Omicron sub variant BA.2 is on the rise in many parts of the world, according to Covid-19 tests conducted over the past two weeks.
Helix, a San Diego-based genomics firm, says BA.2 is present in 50 percent to 70 percent of Covid cases nationwide in the US.
Covid cases are peaking in several East and Southeast Asian and European countries. The surge is fuelled mainly by the BA2 sub-lineage of the Omicron variant. The rapid rise has caused anxiety in India.
Data show that the rise in cases recorded between December 2021 and mid-January 2022 in India (dubbed as the Omicron wave) was in most part due to the BA2 sub-lineage. So, while the sub-lineage has just become dominant in other nations, it became dominant in India as early as January 2022. Moreover, hospitalisation data show that BA2 is milder than the previous variants.
While BA2 is more transmissible than BA1, it has not been shown to cause more severe illness. And even though the virus has evolved considerably since vaccines against it were first developed, the inoculations still work, Dr Maria Van Kerkhove, the WHOās Covid-19 technical lead, said.
‘Our vaccines remain incredibly effective at preventing severe disease and death, including against both of the sublineages of BA.1 and BA.2,’ she said.
Meanwhile, England’s National Health Service (NHS) opened bookings for the fourth Covid-19 vaccine dose for those aged 75 and over and high-risk immunosuppressed individuals as part of its spring booster vaccination programme.
The UK’s independent Joint Committee on Vaccination and Immunisation (JCVI) had advised a spring booster should be offered to those most vulnerable to Covid-19 as a precautionary measure. The additional top up vaccine dose will be given around six months after the last dose of a Covid vaccine.