Data from: Transmission and pathologic findings of divergent human seasonal H1N1pdm09 influenza A viruses following spillover into pigs in the United States
<p dir="ltr">Background: The H1N1 pandemic (H1N1pdm09) lineage of influenza A viruses (IAV) emerged in North America in 2009 and caused a human influenza pandemic. It spread rapidly due to its efficient transmission and limited human immunity, replacing the previous human seasonal H1. Human-to-swine transmission of …