THE NEW Covid sub-variant IS spreading faster than its “sister” Omicron, health chiefs have announced.
But the good news is that vaccines work well against it, with a booster shot crucial for adequate protection.
BA.2 has very similar genetic makeup to the original Omicron strain, called BA.1, and its first global detection was in November.
The UK Health and Security Agency (UKHSA) said there have been 1,072 genomically confirmed cases of BA.2 in England so far – more than double the 426 reported last Friday.
The agency said there is currently no data on the severity of BA.2.
But it is known that the original Omicron strain, which BA.2 is very closely related to, is much milder than previous variants.
Those infected with Omicron are around 50 per cent less likely to end up in hospital compared to those who had Delta.
Professor Tim Spector, lead scientist on the ZOE COVID Study app, believes BA.2 is “not more severe” based on stable hospitalisations in Denmark, where the highest cases have been detected.
The UKHSA said that BA.2 “has an increased growth rate compared to BA.1 in all regions of England”.
Health bosses said: “While growth rates can be overestimated in early analyses of a new variant, the apparent growth advantage is currently substantial.”
Analysis of cases so far shows that people with BA.2 are more likely to pass the strain onto people they live with, called the secondary attack rate.
Some 13.4 per cent of contacts caught the BA.2 bug compared with 10.3 per cent of those in the home of an Omicron patient.
But the good news is that jabs are still highly effective against BA.2 – even more so than the original Omicron strain.
A preliminary assessment showed that vaccine effectiveness was nine and 13 per cent respectively for Omicron and BA.2, after more than 25 weeks.
This increased to 63 per cent for Omicron and 70 per cent for BA.2 two weeks following a booster.
Trending In The News’s Jabs Army campaign is helping get the vital extra vaccines in Brits’ arms to ward off the need for any new restrictions.
Dr Susan Hopkins, Chief Medical Advisor for the UK Health Security Agency, urged people to get the vaccines if they haven’t already, and to take a test if they have Covid symptoms.
She said: “Although hospitalisations and deaths remain low, cases are still high in some areas and some age groups so it’s important that we continue to act cautiously as restrictions are lifted.
“Consider wearing a face covering when in crowded places.”
It comes after data revealed that although BA.2 has only been around for a month or so, it has overtaken Delta.
The Wellcome Sanger Institute claims BA.2 accounted for an estimated 0.8 per cent of cases in the UK in the week to January 15, up from 0.2 per cent a week prior and against Delta’s 0.5 per cent.
Prof Spector said the “sister” sub-variant of Omicron is set to overtake the original within a month.
He said: “One in 20 new cases had this variant last week, and as it’s doubling every few days this should predominate within a month.
“The ZOE data has also seen more confirmed reinfections in recent weeks with around seven per cent of new symptomatic cases having previously tested positive, suggesting a natural infection with Delta may not offer much protection.”
