Jayadevan said the XE variant is the combination of BA.1 and BA.2 where X stands for Recombinant Type and E is the sequence of its discovery. Mutation and recombination are techniques used by viruses to become fitter.

 

The Brihanmumbai Municipal Corporation (BMC) on Wednesday announced that a 50-year-old woman with a travel history to South Africa may have been infected with the newly-discovered 'XE' variant of the coronavirus. However, the Union Health Ministry denied the report which claimed that the first case of COVID-19 variant XE has been detected in India.

 

What has been noticed is that XE could be about 10 per cent more transmissible than the dominant BA.2 variant. But that is a very small advantage that XE has, and even this has not been confirmed as of now.

 

"Over the past 2 and a half years, the COVID-19 virus has been continuously evolving to spread faster between its hosts. By nature, this particular virus wants to spread to more people", said Jayadevan adding that to achieve this, the virus attempts to improve its fitness. In biological terms, the fitness of the virus is defined in two categories - faster transmissibility from one person's cells to another person's cells, and, secondly, immune evasion.

 

"All recombination events need not result in a fitter virus. Some recombinant products could be failures. But when infection in the community goes unchecked and it gets to do this millions of times, like rolling of dice, at one point, a correct sequence happens - where the daughter virus emerges fitter than its parents", Jayadevan told IANS.

 

He said that it forms clusters as it successfully spreads to people, and this gets noticed during genome sequencing. Only these successful sublineages make news which are given names like XD, XE etc, Jayadevan concluded.