Omicron variant

This new variant, emerging in South Africa, has caused alarm around the world. It will be some weeks before we know whether that alarm is justified but in the meantime we can address a different question. What happened to variants Mu, Nu and Xi?

 The Lambda variant was first detected in Peru in August 2020 but was not named by the WHO until June 2021. The Mu variant was identified in Colombia in January 2021 and six months later had spread throughout the Americas. Although having a mutation that allowed it to evade to some degree the current vaccines, it was so swamped by the Delta variant with its much greater transmissibility that after a few weeks it disappeared from sight. This is not to say that it is not lurking there somewhere but at the moment at least it is not causing concern.  

 This new variant should therefore have been called Nu, but the very probable confusion of Nu and new caused the WHO to skip Nu.  The next possible name should have been Xi but again the WHO decided to give it a miss, this time because the spelling is the same as a common Chinese family name, even though the pronunciation is quite different.  And so we have Omicron instead.

 By the time our dealings with COVID are over, we will at least have learnt the Greek alphabet, albeit with a few holes in it.

There are a couple of pronunciation difficulties. Some people are inclined to say [omnicron] under the influence of the familiar prefix omni-. Some people are giving a short o which is correct for the Greek letter while others are giving a long o. The latter will be in trouble when we get to the Omega variant.