WHO should declare Omicron BA.2 a high-risk 'variant of concern': US epidemiologist

On February 20, US epidemiologist Dr Eric Feigl-Ding turned to Twitter to say that the WHO should label the BA.2 sub-strain of the Omicron a Variant Of Concern (VOC). He made this claim based on a study conducted by a Japanese team led by University of Tokyo researchers, which indicated that, like BA.1, the BA.2 subvariant of Omicron appears to primarily evade the immunity elicited by COVID-19 vaccinations.

"It is now 100% clear that the @WHO needs to declare #Ba2 a high-risk “variant of concern”. Dear @mvankerkhove @doctorsoumya @DrTedros @gabbystern @DrMikeRyan — please make it so. VOC declaration of BA2 now ASAP! ," Ding tweeted.

In response, Maria Van Kerkhove, WHO's Covid-19 technical lead, stated, "BA.2 is already a VOC. It is Omicron."

"Neutralisation experiments show that the vaccine-induced humoral immunity fails to function against BA.2 like BA.1," the study's authors wrote. In November 2021, Omicron was initially discovered in Botswana and South Africa. Its BA.1 sub-variant has now spread fast around the world, outcompeting other varieties like Delta.

Omicron BA.2 lineage was discovered in February this year

Another Omicron subvariant, the BA.2 lineage, was discovered in various nations, including Denmark and the United Kingdom, in February of this year. According to the researchers, BA.2 has begun to outcompete BA.1, implying that it is more transmissible than the original Omicron. Although BA.2 is classified as an Omicron variant, its genomic sequence differs significantly from that of BA.1, implying that BA.2's virological properties are distinct from those of BA.1, the researchers wrote.

Ding had described the scenario as "worrisome" and "bad news" just a day before. Worrisome—New lab experiments from Japan show that #BA2 may have features that make it as capable of causing serious illness as older variants–including Delta! And yet as evasive as old #Omicron cousin BA1. #BA2 surging—needs an upgrade to VOC asap (sic)," Ding earlier tweeted. 

Although BA.2 is more transmissible than BA.1, the World Health Organization (WHO) announced last week that it is not more severe. Omicron was initially discovered in Botswana and South Africa in November of last year. Since then, the BA.1 subvariant has been discovered in a growing number of nations, outperforming older variants like Delta.

(With inputs from agencies)

Image: Dr. Eric Feigl-Ding/Facebook/AP/Pixabay