There are three types of human influenza viruses: influenza virus A (IVA), influenza virus B and influenza virus C2,5. Type A virus is the most virulent of the three and causes the most serious disease. In addition to humans, it also infects animals such as birds, pigs, horses and bats6. Until now, only the type A virus has been known to cause pandemics due to the risk of zoonotic infections caused by host switch2,7. The type B virus infects almost exclusively humans8, but also seals9 and ferrets10 can be infected. Due to the limited host spectrum and less antigenic change, no pandemics are caused by this type11. Type C virus infects humans, pigs and dogs. It is less common than the other two types, and causes mostly only mild respiratory
There are three types of human influenza viruses: influenza virus A (IVA), influenza virus B and influenza virus C2,5. Type A virus is the most virulent of the three and causes the most serious disease. In addition to humans, it also infects animals such as birds, pigs, horses and bats6. Until now, only the type A virus has been known to cause pandemics due to the risk of zoonotic infections caused by host switch2,7. The type B virus infects almost exclusively humans8, but also seals9 and ferrets10 can be infected. Due to the limited host spectrum and less antigenic change, no pandemics are caused by this type11. Type C virus infects humans, pigs and dogs. It is less common than the other two types, and causes mostly only mild respiratory