BA.2 variant surges across Western Europe, US, China; what about India?

There has been a surge in coronavirus cases across Western Europe and the United States (US) and China has imposed restrictions in multiple cities like Shenzhen and Changchun to stem the outbreak. 

Other countries that have reported a spike in the COVID cases are Vietnam, Germany, South Korea and France.  

All these developments have been tied to the BA.2 sub-variant of the Omicron variant of the novel coronavirus. 

Why are COVID-19 cases rising in Europe?   

Head of research cell at IMA-Kochi Dr Rajeev Jayadevan told India Today, “The slow rise in admissions and hospitalisation, mainly from the BA.2 sub-lineage in Europe, is due to a combination of lax restrictions as well as waning immunity after their most recent vaccine dose. The rise of BA.2 is not exponential because there is still some residual immunity in Europe from BA.1 Omicron wave.”  

BA.2 sub-variant breaks out in China  

Chinese media group Caixin Media reported that “in the hardest hit provinces of Yunnan, Jilin and Guangdong, local governments have designated lockdown areas to prevent the virus from spreading.” 

It further said, “More governments have designated lockdown areas to prevent the virus from spreading. More than 20 regions in China have experienced COVID-19 outbreaks since the beginning of this year.” Chinese authorities have claimed that the rise in cases is due to the BA.2 ‘stealth’ sub-variant. 

The National Health Commission said that a total of 3,507 domestically transmitted cases with confirmed symptoms were reported on Monday across over 12 provinces and municipalities and most of the new cases were in the northeastern province of Jilin. 

According to Dr Jayadevan, China is witnessing a rise in cases as it faced challenges in vaccinating its older population due to widespread vaccine hesitancy. 

BA.2 sub-variant in the US   

The Omicron BA.2 sub-variant had been circulating in the US for some time, with roughly 35,000 cases as of Tuesday (March 15), the White House claimed. 

White House spokesperson Jen Psaki stated that the tools the US had – vaccines and medicines—were all effective against the virus. 

As per the US Centers for Disease Control and Prevention (CDC), BA.2 sub-variant of Omicron makes up around 23.1 per cent of the coronavirus variants circulating in the US as of March 12. The subvariant makes up 39 per cent of the total cases in New Jersey, New York, Puerto Rico and the Virgin Islands. 

How dangerous is the BA.2 sub-variant?   

The World Health Organisation (WHO) claims that though the BA.2 sub-variant has a growth advantage over BA.1, it does not cause more severe infection. 

The global health organisation said, “BA.2 sublineage should continue to be considered a variant of concern and that it should remain classified as Omicron.” 

Will this have an effect on India’s coronavirus graph?   

According to Dr Jayadevan, “This is almost like a tree branch that is continuously growing.” 

“In China, the situation is that they have very little hybrid immunity – unlike India. This means that even though they are vaccinated to a large extent, we know that vaccine protection against infection only lasts for a few months, even though protection from severe disease lasts long term," he said.

Dr Jayadevan further explained that "the situation in India and South Africa is that in addition to ongoing vaccination process, there is a parallel process of natural infection, reinfection and breakthrough infection, each of which is increasing the collective immune memory to the virus in the community. Thus, there was a rapid and sustained drop off in cases after the recent Omicron surge in these countries.” 

Head of the COVID-19 Task Group in the National Immunisation Technical Advisory Group (NTAGI) Dr NK Arora has a slightly different take than that of Dr Jayaraman. 

Dr Arora said that the fourth COVID-19 wave will be driven by the BA.2 sub-variant. “The fourth wave will be driven by a new variant since BA.2 is present in 75 per cent of the population. Can’t say when India will witness the fourth wave. Vaccines available now do not cover Omicron to the extent that boosters will benefit,” he said. 

About the BA.2 sub-variant   

• BA.2 is a sub-lineage of the Omicron variant, which was first identified in South Africa in November 2021. 
• BA.2 has lots of mutations and about 20 of them in the spike protein that studs the outside of the virus are shared with the original Omicron. 
• WHO stated that the surge in cases is not only limited to China and Western Europe. 

(With inputs from Sneha Mordani, agencies)