It was not detected again until September when it reappeared among samples in California, but numbers remained very low until November.
However, no further studies were conducted to prove the behaviour of the variant, and soon the world got involved in understanding the Omicron strain which had already started wrecking havoc in parts of South Africa.
It was identified in 12 patients in the Southern Alps around the same time the highly transmissible was surging in South Africa, officials said.
After the announcement, leading virologists said there was insufficient data to support labelling the variant as a distinct variant of concern, pointing to the small number of patients studied.