Genetic testing of people who died in Kyrgyzstan eight years before plague reached Europe reveals an ancient strain of the bacterium Yersinia pestis.

The presence and spread of new, more-infectious and immune-evading variants show that the coronavirus is not done mutating.

This strain of SARS-CoV-2 is causing new outbreaks in Europe and Asia and may spread slightly faster than the better-known BA.1 Omicron subvariant, although it’s too early to say for sure.

As Omicron induces a sense of deja vu at the close of the year, we look back at a few key ways in which our understanding has moved forward.

Preliminary studies suggest that existing vaccines falter in preventing symptomatic infections caused by the new coronavirus variant, but protection against severe disease is still high.

Different variants of the virus behind the COVID-19 pandemic are swapping chunks of genetic material, but it’s not yet clear what implications that may have for public health.

Rather than being described by the location of where they emerged or an alphanumeric code, variants will be given a Greek letter.

Researchers find that SARS-CoV-2 variants can evade primer-probe sets and recommend that diagnostic assays include multiple targets for reliability.

While some experts speculate the variant could be partially responsible for India’s current surge in SARS-CoV-2 infections, information about the effects of its mutations is only beginning to emerge.

Martha Nelson of the National Institute of Allergy and Infectious Diseases talks about the need to balance data sharing and patient privacy concerns when tracking the spread of variants.

A treatment of two monoclonal antibodies against SARS-CoV-2 is ninefold less effective in the lab against the B.1.351 variant than against the dominant version of the virus.

Engineered viruses that don’t replicate provide a tractable model for scientists to safely study SARS-CoV-2, including research into vaccine efficacy and emerging variants.

B.1.525 shares a mutation with the B.1.351 variant first detected in South Africa that seems to allow the virus to dodge the immune system.

Facing new variants of SARS-CoV-2, some vaccines may offer more robust protection or be more easily redesigned to target them.

With many millions of people waiting several weeks to receive a second COVID-19 vaccine dose in some countries, experts consider the possibility that SARS-CoV-2 could evolve vaccine resistance.

Here’s our brief guide to the most noteworthy mutations in the novel coronavirus.

It’s too early to know whether the L452R version of SARS-CoV-2 is highly infectious like the B.1.1.7 UK variant that is also spreading around the US.

From new treatments to an investigation into the virus’s origins, here are some of the developments we can expect this year.

An engineered coronavirus with the N501Y mutation—one of many mutations present in the emerging B.1.1.7 and 501.V2 variants of the coronavirus—is neutralized by the sera of COVID-19 vaccine recipients.