What is a recombinant variant? 5 things WHO said amid fears over new XE strain

A new strain has sparked fresh concerns after the world saw a rise in Covid cases in the first two weeks of March.

The XE strain – first detected in the United Kingdom in January – is said to be a recombinant variant, which refers to recombination of genetic material.

As per the infomation available on the website of the US-based National Center for Biotechnology Information, viruses are continuously changing as a result of genetic selection.

"They undergo subtle genetic changes through mutation and major genetic changes through recombination. Mutation occurs when an error is incorporated in the viral genome. Recombination occurs when coinfecting viruses exchange genetic information, creating a novel virus," reads an excerpt from W Robert Fleischmann, Jr's Medical Microbiology.

Another recombinant variant that had recently triggered worries was Deltacron, said to be a combination of Delta and Omicron – both believed to be highly infectious.

Here are five things that the WHO has said in its latest report about the XE variant:

1. The XE strain is a recombinant variant of BA.1 and BA.2 sublineages of Omicron, the world body said.

2. It was first detected in the United Kingdom on 19 January and more than 600 sequences have been reported and confirmed since.

2. The WHO has said that early-day "estimates indicate a community growth rate advantage of around 10% "as compared to BA.2". "However this finding requires further confirmation," the world body said.

3. XE belongs to the Omicron variant until significant differences in transmission and disease characteristics, including severity, may be reported, the WHO has said as it finds more about the new strain.

4. "WHO continues to closely monitor and assess the public health risk associated with recombinant variants, alongside other SARS-CoV-2 variants, and will provide updates as further evidence becomes available," it added.

5. Omicron has been reported to be the dominant strain worldwide with 99.7% of the fresh samples belonging to the variant, according to the WHO.

Amid the findings, it may be noted that the BA.2 sublineage of the Omicron variant, also highly transmissible, was believed to have led to a massive spike in Europe and China in March.