Explained: What are BA.4 and BA.5 Covid variants?
The COVID-19 pandemic never fails to surprise us, unpleasantly though. Each time we hope that it’s on the ebb, the virus bounces back with new variants like Delta and Omicron. Latest media reports suggest that two sub-variants of Omicron, BA.4 and BA.5, have been detected in over a dozen countries. Well, this has led to a fresh surge in COVID-19 cases across the world, according to the World Health Organisation (WHO). So, what exactly are these BA.4 and BA.5 varieties of the virus? What are the differences between them and the others found previously? Let us find out.
What are the BA.4 and BA.5 sub-variants?
BA.4 and BA.5 are two new Omicron lineages. They are still categorised as the Omicron variation for now. In other words, they are Omicron viruses with a fresh set of mutations, changes in DNA sequence of a virus/ organism. BA.4 and BA.5 carry mutations across their genomes with both BA.1 and BA.2 (also Omicron lineages). However, they are most related to BA.2, say experts. The European Centre for Disease Prevention and Control (ECDPC), which develops Europe's defences against the infectious disease, has already designated BA.4 and BA.5 Omicron variations as Variants of Concern on May 12, 2022. “For these variants, clear evidence is available indicating a significant impact on transmissibility, severity and/or immunity that is likely to have an impact on the epidemiological situation in the EU/EEA,” the ECDPC said in a release about BA.4 and BA.5.
Where have these sub-variants been reported?
Estimates of WHO suggest that Omicron sub-variants BA.4 and BA.5 have been found in more than a dozen nations, fuelling COVID outbreaks around the world all over again. In fact, if you were to believe WHO's technical lead on COVID-19, Maria Van Kerkhove, then, at least 16 countries have reported about 700 instances of BA.4. BA 5, on the other hand, has been detected in at least 17 countries where there have been reports of 300 cases. Notably, the first case of BA.4 has also been found in our own country. Telangana witnessed the first case on 18th May.
Are these COVID variants actually new?
Since there have been so many variants and sub-variants of the novel coronavirus, it might be difficult to comprehend what distinguishes one from the other. Isn't it? But the fact is, the new sub-variants aren't all that new. They were discovered in South Africa in January this year. According to the National Institute of Communicable Disease, South Africa, BA.4 and BA.5 were the main variants in circulation in South Africa over the next four months. They had replaced 55% of the other Covid-19 variants.
Can these sub-variants cause more hospitalisations?
The answer is no. This comes as a huge relief for sure. BA.4 and BA.5 do not appear to be increasing hospitalisation and deaths in South Africa. However, the number of cases may increase, particularly among people with low immunity.