Have you ever wondered why you have to get a flu shot every year, but some vaccines are one-and-done? It all has to do with how and how fast viruses evolve - and that depends on mutation rates.

Helen Branswell covers issues broadly related to infectious diseases, including outbreaks, preparedness, research, and vaccine development. Follow her on Mastodon and Bluesky. You can reach Helen on ...

New research shows how small shifts in the molecular makeup of a virus can profoundly alter its fate. These shifts could turn a deadly pathogen into a harmless bug or supercharge a relatively benign ...

A genetic analysis sheds light on when the outbreak began, how the virus spread and where it may be going. By Apoorva Mandavilli and Emily Anthes The bird flu virus sweeping across dairy farms in ...

A phylogenetic tree of SARS-CoV-2 sequences, built with Nextstrain, displays sequences colored by their clade and organized by collection date. Over time, sequences mutate and diverge, forming new ...