Family: Orthomyxoviridae Genus: Influenza A Virus H1N1 circulates throughout world, including US H3N2 found in US Single Stranded (-) RNA Segmented 8 segments Enveloped Helical Replicates in Nucleus
Pigs High morbidity Low mortality Commonly seen in Winter
Direct contact Nasopharyngeal route Virus shed in nasal secretions Aerosol spread Virus is easily carried and spread by waterfowl
24 to 72 hours
Acute Respiratory Disease Virus replicates in the epithelium of the nasal, tracheal, and bronchial mucosa This predisposed the animal to secondary bacterial infections, most often with Pasteurella multocida or Haemophilus spp.
High fever Lack of appetite Inactivity/ weakness Paroxysmal coughing Sneezing Irregular breathing Rhinitis with nasal discharge Ocular discharge
Aujeszky's disease Atrophic rhinitis Enzootic (mycoplasmal) pneumonia Bacterial pneumonia due to Pasteurella or Haemophilus spp.
Treatment and Prevention
Animals recover in 3 - 6 days Supportive Antibiotics for secondary infections Vaccines available (limited value) Pigs are important factor in spread of Influenza viruses Pigs are able to contract and spread avian and human influenza thus giving viruses a chance to mutate Zoonotic Close contact with infected pigs