Aug 28, 2025 · Some variants will emerge and disappear, while others will emerge and continue to spread and may replace previous variants. It is important to track the emergence of variants so that …

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 …

Positive, negative, and neutral mutations during the evolution of coronaviruses like SARS-CoV-2. Variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are viruses that, while …

Dec 24, 2025 · Get the latest COVID-19 news from infectious diseases expert Mark Rupp, MD, including COVID-19 case rates, types of variants circulating and vaccine updates.

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!

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 …

3 days ago · Flu is rising rapidly across the U.S., driven by a new variant of the virus. The Centers for Disease Control and Prevention reported Tuesday that after a slow start to flu season in early …

Dec 17, 2025 · Here’s what to know about the dominant version of the virus that’s circulating now.

Sep 24, 2025 · The Stratus COVID-19 variant has been fueling a rise in cases across the country. Stratus is currently the dominant variant in the U.S. This variant is slightly more infectious than …

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 …