How Omicron, the New Covid-19 Variant, Got Its Name

Some of the better-known variants, such as Delta, rose to a variant of concern. Others in that category were named Alpha, Beta and Gamma. Others that emerged, which were variants of interest, were named Lambda and Mu. Other Greek letters were used for variants that did not meet those thresholds but Nu and Xi were the only ones that were skipped.

The W.H.O. has promoted the naming system as simple and accessible, unlike the variants’ scientific names, which “can be difficult to say and recall, and are prone to misreporting,” it said.

Some researchers agree.

Dr. Angela Rasmussen, a virologist at the University of Saskatchewan, said she conducted many interviews with reporters this year, before the Greek naming system was announced, and she stumbled through confusing explanations about the B.1.1.7 and B.1.351 variants. They are now known as Alpha, which emerged in the United Kingdom, and Beta, which emerged in South Africa.

“It makes it really cumbersome to talk about when you’re constantly using an alphabet soup of variant designations,” she said, adding, “Ultimately people end up calling it the U.K. variant or the South African variant.”

That’s the other big reason that the W.H.O. moved to the Greek naming system, Dr. Rasmussen said: The older naming convention was unfair to the people where the virus emerged. The agency called the practice of describing variants by the places they were detected “stigmatizing and discriminatory.”

The practice of naming viruses for regions has also historically been misleading, Dr. Rasmussen said. Ebola, for example, is named for a river that’s actually far from where the virus emerged.

“From the very beginning of the pandemic, I remember people saying: ‘We called it the Spanish flu. Why don’t we call it the Wuhan coronavirus?’” Dr. Rasmussen said. “The Spanish flu did not come from Spain. We don’t know where it emerged from, but there’s a very good possibility it emerged from the U.S.”