Influenza A virus subtype H1N1

Influenza A virus subtype H1N1 (A/H1N1) is a subtype of influenza A virus (IAV). Some human-adapted strains of H1N1 are endemic in humans and are one cause of seasonal influenza (flu).

Source: Wikipedia — Influenza A virus subtype H1N1 (CC BY-SA 4.0)