Here's the latest variant picture for Western Australia:

The XBF "Bythos" recombinant lineage has surged to dominate the intensely chaotic swarm (26%). XBF has been dominant in Victoria throughout the current wave and is now growing in other states, also in New Zealand, Sweden and others. XBF "Bythos" is rated just below XBB.1.5 "Kraken" for immune escape, and slightly higher for ACE2 binding, so it's success should not be a surprise.

The new XBC.1.1 recombinant "Deltacron" lineage is also showing strong growth (16%). It's grand-parent XBC was a combination of BA.2 and B.1.617.2* (Delta), presumed to originate in the Philippines. XBC.1.1 has evolved through a couple of generations with extra mutations, which appear advantageous.

XBC.1.1 is quite rare outside Australia, and is at low frequencies (1-2%) in other states. So WA will be keenly watched, as the launchpad of what I beleive is already the most succesful "Deltacron" lineage anywhere, ever.

The earliest sample reported of XBC.1.1 was from Queensland in October, so it looks like another successful Australian contribution to the global diversity of SARS-CoV-2.

The CH.1.1 "Orthrus" lineage has faded recently against intense competition, not making the top 7.

Recent sample sizes are smaller.

#COVID19 #Australia #WA #XBF #XBC_1_1 @auscovid19
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