Pathogenesis

PATHOGENESIS
  • Young or previously unexposed animals are highly susceptible. Stress factors contribute to the development of disease.
  • The capsule and cytotoxic factor are thought to be virulence factors and endotoxin may play a role in the disease process.
  • During stress, the bacteria may invade the mucosal barrier. The invasive mechanism is not known.
  • In respiratory tract initially nasopharyngitis. If this infection is not checked, it may lead to sinusitis, otitis media and pneumonia.
  • If a bacteraemia develops, joint infections and meningitis may follow.
  • Diseases caused by the Haemophilus species
Species
Host
Disease
H. somnus
Cattle

Sheep
Thrombo embolic meningo encephalitis (TEME) (Sleepers)
Pneumonia and pleurisy
Arthritis
Endometritis and abortion
Epididymitis and orchitis in rams
H.parasuis
Pigs
Polyserositis and meningitis in young pigs (Glasser’s disease )
H.paragallinarum
Poultry
Infectious coryza
H.influenzae
Human
Variety of diseases ranging from respiratory infections to meningitis

 
Last modified: Monday, 4 June 2012, 5:26 AM