Omicron sub-variant BA.2: What do we know so far?
A new sub-variant of the highly-infectious Omicron variant of coronavirus has emerged in dozens of countries, sparking fears. In fact, health authorities in the United Kingdom have designated the sub-strain, called BA.2, as a "variant under investigation." BA.2 might be more transmissible than the original Omicron sub-variant BA.1, experts say. Here's what you need to know about it.
BA.2 has shown a significant growth across countries. It shares 32 mutations with BA.1 and also carries 28 unique mutations. Some experts claim that BA.2 does not have the particular mutation seen with BA.1 that helps in easily distinguishing it from the Delta strain. The government in Denmark, however, said there is no difference in hospitalizations for both the sub-variants, according to initial analysis.
The Omicron variant has three sub-strains: BA.1, BA.2, and BA.3, the World Health Organization (WHO) said, adding that 99% of the Omicron cases were linked to first of the three. As far as BA.2 is concerned, authorities in Britain have sequenced 426 infections. UK officials said 40 countries have reported BA.2 cases, with Denmark leading the tally, followed by India, Britain, Sweden, and Singapore.
In Denmark, BA.2 has spread rapidly in recent weeks. The sub-variant accounted for 20% of COVID-19 cases in the final week of 2021 but that number rose to 45% in the second week of January 2022. "It may be that it is more resistant to the immunity in the population, which allows it to infect more," said Anders Fomsgaard, researcher at Statens Serum Institut.
Omicron, the most highly transmissible coronavirus variant so far, was first detected in southern Africa in November 2021. It has since spread to more than 100 countries, triggering massive outbreaks in the United States, the UK, India, and other regions. Amid the Omicron's spread, the global COVID-19 tally crossed 300 million (30 crore) earlier this month.
"It is the nature of viruses to evolve and mutate, so it is to be expected that we will continue to see new variants emerge," Dr. Meera Chand, Incident Director at the UK Health Security Agency (UKHSA), said, according to Reuters. "Our continued genomic surveillance allows us to detect them and assess whether they are significant," she added.
