Newcastle Disease Virus



Also known as NDV

Hosts

  • Gallinaceous birds, pigeons, parrots, finches
  • Subclinical carriers: ducks, ostriches
  • Causes conjunctivitis in humans

Pathogenesis

  • Transmission via aerosol and direct contact
  • Disease ranges from subclinical respiratory tract infections -> torticollis -> haemorrhages and death

Diagnosis

Two diagnostic tests currently exist:

  • Animal test:
    • Samples of trachea and gut of 20 birds are tested in eggs
    • HI using anti-NDV serum (to differentiate HA caused by avian influenza
    • Virulence of isolate tested by the speed it kills chicks
  • DNA test (which will soon replace the animal test):
    • Sequencing the cleavage site of H gene
    • The more basic amino acids the more virulent the virus

Control

  • Newcastle Disease is NOTIFIABLE
  • Vaccination of chickens and racing pigeons
  • Surveillance of imported exotic birds
  • Isolation of infected stock
  • Infected premises to be culled and firebreak cull if spread