<unk>  flu (also<unk>  refers to influenza caused by any virus of the family Orthomyxoviridae, that is endemic to pig<unk>  populations.  Strains endemic in<unk>  are called<unk>  virus (SIV), and all known strains of SIV are classified as Influenzavirus A (common) or Influenzavirus C (rare). Influenzavirus B has not been reported in<unk> .  All three clades, Influenzavirus A, B, and C, are endemic in humans.
People who work with poultry and<unk> , especially people with intense exposures, are at risk of infection from these animals if the animals carry a strain that is also able to infect humans. SIV can mutate into a form that allows it to pass from human to human. The strain responsible for the 2009<unk>  flu outbreak is believed to have undergone this mutation.
In humans, the symptoms of<unk>  flu are similar to those of influenza and of influenza-like illness in general.
Swine influenza
Freshers' Flu
Avian influenza
Influenza
Pertussis
Anthrax
COVID-19-associated Guillain-Barre syndrome
Hay fever