XAY Delta-Omicron recombinant under observation

Africa, Coronavirus, Evolution, Genome, Health, Infection, Recombination, Research, South Africa, Testing, Transmission, XAY

A new SARS-CoV-2 recombinant lineage from South Africa has been highlighted by Tulio de Oliveira, Director of the Centre for Epidemic Response & Innovation in South Africa today.

The Delta/Omicron recombinant was first identified on the 28 June 2022 and designated as XAY on the 25th August 2022


Comparing recent NGS-SA reports, you can see XAY making an appearance this week with about a dozen or so sequences (with red arrows). It’s not a lot, but worth keeping an eye on.

NGS-SA report for the 26th August 2022:


The same chart from the NGS-SA report for the 19th July 2022:


Delta/Omicron (‘Deltacron’) recombinants haven’t been particularly successful in competing with Omicron sublineages so far, but XAY seems to have gained a toehold in Limpopo and Gauteng, South Africa.


Github designation page




We will update this post with any fresh information on XAY as it becomes available.



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Photo by Hans-Peter Gauster on Unsplash


** This post was originally published on August 26, 2022 **