What is XE variant of coronavirus, and why you need not worry about it, know why

The Brihanmumbai Municipal Corporation (BMC) on Wednesday (April 6) 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.

XE, a sub-variant of Omicron, which caused the third wave of Covid-19 this winter, had not been found in India until now. The announcement about its discovery sparked concern about the possibility of a fresh wave of infections in India, where Covid-19 cases are in continuous decline, and are now at their lowest level in more than two years.

Almost immediately, however, Union Health Ministry sources in New Delhi clarified that the identification of the XE variant in that particular patient was yet to be confirmed. In fact, a preliminary analysis had suggested that the virus detected in the patient was not the XE variant.

A confirmation one way or the other was expected in a day or two.

The Omicron variant, which is responsible for over 90 per cent of the infections detected this year, has two prominent sub-variants, called BA.1 and BA.2. There is a BA.3 sub-variant as well, but that is less common.

During the initial phase, the BA.1 sub-variant was the most widespread. In India, however, it was the BA.2 that was the most dominant during the third wave.

BA.2 was found to be slightly more transmissible than BA.1, even though it was not more dangerous. In the last couple of months, the BA.2 variety has become the most widespread across the globe, accounting for almost 94 per cent of all Omicron infections in the last one month, according to the World Health Organisation (WHO). The incidence of the BA.1 variety is declining sharply.

The XE variant is what is called a 'recombinant'. This means it contains the mutations found in BA.1 as well as BA.2 varieties of Omicron. This was first discovered in the United Kingdom in January, and so far more than 600 samples of XE have been found in different countries.

Recombinant variants are not uncommon. Variants that contain mutations characteristics of two or more known variants occur all the time. In fact, variants that contain the characteristic mutations of Delta and Omicron have also been identified.

The random process of genetic mutations in viruses and other organisms keeps happening continuously. But only a small fraction of these mutations significantly alter the abilities of the virus to infect, or to cause severe diseases.