Historically, the WHO regularly listed updates on variants of concern (VOC), which are variants with an increased rate of transmission, virulence, or resistance against mitigations, like vaccines.

Dec 2, 2024 · When these changes become significantly different to a previously detected virus, these new virus types are known as “variants.” To identify variants, scientists map the genetic material of …

Aug 28, 2025 · New variants of SARS-CoV-2 are expected to continue to emerge. Some variants will emerge and disappear, while others will emerge and continue to spread and may replace previous …

Oct 12, 2025 · A strain is when a virus has so many variants that it starts acting differently—for example, it’s much more transmissible than the previous version. All strains are variants, but not all variants …

Nov 29, 2021 · Any change to the viral genetic sequence during this process is known as a mutation, and viruses with new mutations are sometimes called variants. Variants can differ by one or multiple …

Jun 18, 2025 · Here, you can find out what mutations define a variant, what impact they might have (with links to papers and resources), where variants are found, and see the variants in Nextstrain builds!

The emergence of SARS-CoV-2 variants has significantly impacted the global response to the COVID-19 pandemic. This review examines the genetic diversity of SARS-CoV-2 variants, their roles in …

May 30, 2025 · What is a variant, and where do variants come from? A variant is a subgroup of viruses within a species that share an inherited set of distinctive changes in their genetic code.

Discover how COVID-19 2026 looks now, including new COVID-19 symptoms, what to know about each new COVID-19 variant, and when to test or seek care.

Oct 24, 2025 · Concern over variants, sometimes called strains, of the virus that causes COVID-19 is based on how the virus might change. A virus could get better at infecting people, spread faster or …