The Omicron variant of COVID-19 has been named a “variant of concern” by the World Health Organization, but it’s far from the first mutation of the virus to receive major global attention as the next huge threat.
The facts are still coming in on Omicron, but for the time being, all that’s known is that its epicenter of spread is southern Africa and it appears to be more contagious than the Delta variant that recently swept across the United States. Still, the 32 mutations on the spike protein of the strain were reason enough for the WHO to make the declaration that it’s a “variant of concern.”
What does that mean though, exactly? So far, Omicron is the fifth variant of COVID-19 to receive that label from the world’s leading health body. The others are the original strain now known as the Alpha variant, the aforementioned Delta variant, and two others: the Beta and Gamma variants.
The Beta variant was first identified in December 2020 in South Africa, but later researchers estimated it had been spreading since the summer before. As of July 2021, less than 30,000 global cases of COVID-19 were confirmed to be of the Beta variety, according to GISAID.
Scientists believed the variant was more likely to cause severe disease in young people, but fears about it escaping vaccine immunity proved overblown, as Pfizer reported its jab was still highly effective at stopping serious illness and death from the strain. (RELATED: New COVID-19 Variant Causes Alarm For Some Scientists Over Possible Vaccine Resistance)
The Gamma variant was identified by Japanese scientists in January 2021 in travelers who had recently returned from Brazil. It was then determined that Gamma, which has ten mutations on its spike protein, was in widespread circulation in Brazil. As of June 2021, only around 63,000 cases of Gamma were confirmed by GISAID, and the strain never made the global impact Delta did, especially in the United States.
Some scientists warned that the Lambda variant had a better chance than the Delta variant to escape vaccines… but Lambda never “caught on,” so to speak; as of earlier this month, 99 percent of the identified strains of COVID-19 were the Delta variant.https://t.co/s9ic0PGtqz
— Jim Geraghty (@jimgeraghty) November 29, 2021
Beyond variants of concern, two others were labeled by the WHO “variants of interest”: Lambda and Mu. Both were identified in South America, Lambda in September 2020 and Mu in January 2021. Both led to pearl-clutching from some popular epidemiologists, but the impact of both on the United States has been negligible. (RELATED: Countries Implement Travel Restrictions As New Coronavirus Variant Identified In South Africa)
— Eric Feigl-Ding (@DrEricDing) March 28, 2021
Then, there are a whole host of other strains that were once labeled variants of interest by the WHO but are no longer considered such: Epsilon, which the Centers for Disease Control and Prevention labeled a variant of concern for several months earlier this year; Zeta, another variant of Brazilian origin; Eta, first detected in the United Kingdom and Nigeria last December; and others like Theta, Iota and Kappa. But none have ultimately lived up to the hype, and it remains to be seen if that will be the case for Omicron, too.