What We Know About the New Covid Variant, Omicron

Citing the potential for waning immunity six months or more after vaccination, some health experts are promoting booster shots to increase antibody levels.

Dr. Fauci has urged people to get a booster shot, which he said would most likely provide additional protection against severe disease. “We’ve said it over and over again and it deserves repeating. If you’re not vaccinated, get vaccinated, get boosted if you are vaccinated, continue to use the mitigation methods, namely masks, avoiding crowds and poorly ventilated spaces,” he said on Tuesday.

The Coronavirus Pandemic: Key Things to Know

Biden’s winter Covid plan. As Omicron reached the U.S., President Biden announced a new pandemic strategy that includes hundreds of family-centered vaccination sites, booster shots for all adults, new testing requirements for international travelers and insurance reimbursement for at-home tests.

Moderna, Pfizer-BioNTech and Johnson & Johnson, makers of vaccines approved for use in the United States, and AstraZeneca, which is widely used in Europe, have all said they were studying Omicron, and they expressed confidence in their ability to tailor their formulations to target the variant.

Why is it called Omicron?

When the W.H.O. began to name emerging variants of the coronavirus, they turned to the Greek alphabet — Alpha, Beta, Gamma, Delta and so on — to make them easier to describe. The first “variant of concern,” Alpha, was identified in Britain in late 2020, soon followed by Beta in South Africa.

But veterans of American sorority and fraternity life might have noticed the system has skipped the next two letters in the alphabetical order: Nu and Xi.

Officials thought Nu would be too easily confused with “new,” but the next letter, Xi, is a bit more complicated. W.H.O. officials said it was a common last name, and therefore potentially confusing. Some noted that it is also the name of China’s top leader, Xi Jinping.

A spokesman for the W.H.O. said the organization’s policy was designed to avoid “causing offense to any cultural, social, national, regional, professional, or ethnic groups.”