They also skipped over Nu. (Lots of early reports on Omicron call it Nu because that is what was next.)
I can only assume they skipped Nu because they didn't want a "WHO's on First?" series of joke puns about the "New-Nu virus".
"Xi" probably because of the name confusion with the politician.
CLAIM: The World Health Organization skipped two letters of the Greek alphabet, nu and xi, when naming omicron, a newly identified variant of the coronavirus. AP’S ASSESSMENT: True.
apnews.com
In a statement provided to the AP, the WHO said it skipped nu for clarity and xi to avoid causing offense generally.
“‘Nu’ is too easily confounded with ‘new,’ and ‘Xi’ was not used because it is a common last name,” the WHO said, adding that the agency’s “best practices for naming disease suggest avoiding ‘causing offence to any cultural, social, national, regional, professional or ethnic groups.’”
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I feel like the WHO couldn’t really win on variant names.
Obviously, the soft heads and crazies are gonna do their thing no matter which conventions you use.
But as far as functional adults go. What are other systems of sequence that would meet all the criteria?
Roughly:
1) A system that replaces the use of the geographic location of origin for an emerging variant and substitutes for number/letter designation (B.1.1.529) which is a little wordy.
2) A system that indicates its own location in a commonly understood sequence, like Alpha to Omega with 22 predictable letters/symbols/words in order between.
c) Doesn’t cause offence.
Presumably they considered NATO phonetic and rejected it. Which I could understand because of the politics of it all.
Maybe Latin numbers? It would be funny to hear them pronounced.