How to follow the confusing names for COVID-19 variants and know which ones to be concerned about
a COVID-19 variant known as FL.1.5.1 was responsible for an estimated 13% of infections, according to virus tracking data from the Centers for Disease Control and Prevention. But despite a surge in COVID-19 cases this summer that continues to rise as the school year starts, you may not have even heard of this variant. FL.1.5.1 is an alias for XBB.1.9.2.1.5.1, which descends from Omicron and is colloquially called Fornax. If you’re confused about what this variant soup of names means and why you should care, you’re not alone.
The World Health Organization (WHO) has criteria for determining which variants rise to a high enough threat level to warrant a Greek letter designation like Alpha, Delta or Omicron. Whether a variant rises to the level of a Greek letter designation or not, every variant gets a numeral name in the Pango naming system related to its genetic makeup, like XBB.1.5, which has driven the vast majority of infections in 2023 in the U.S.
The virus has mutated thousands of times and will continue to do so, but not every mutation is advantageous or makes things worse for humans. Only some strains transform in such a way that they become notably more infectious or problematic. Most fade away without doing much harm and some likely exist but aren’t even on our radar.
In 2021, more than a dozen “variants of concern” or “variants of interest” were considered to pose enough of a threat to be assigned Greek letters. But no Greek letter designations have been given since Omicron was named in November 2021, partly because the WHO changed its designation system to no longer give letters to the lower severity classification, variants of interest.
“Since March 2023, WHO only gives names to new variants of concern,” the WHO told Salon in an email. “This is true even if the new variant stems from Omicron.”
Omicron shows no signs of disappearing one and a half years after it was first identified.
Some scientists are calling for an updated naming system that lowers the bar for what the WHO considers a “variant of concern,” so that we can move on from Omicron and get people, many of whom have checked out of the pandemic, to pay attention to it again, said Victoria Easton, Ph.D., a virologist at the University of Leeds.
“If you just label it as Omicron, it’s like this is unchanging, and it’s kind of to be forgotten,” Easton told Salon in a phone interview. “But it really shouldn’t be, because it’s still current.”
Omicron has been the top-circulating family of COVID-19 variants since it came on the scene in 2021 and shows no signs of disappearing one and a half years after it was first identified.
