Difference between revisions of "Newcastle Disease Virus"

Revision as of 18:43, 29 September 2010

Description

Newcastle disease virus is the causative agent of Newcastle Disease, an acute viral disease of domestic poultry and many other bird species that is usually fatal.

Transmission

Infected birds shed the virus through droppings and secretions from the nose, mouth and eyes. The virus may also be present in eggs laid during the clinical disease. The virus is commonly transferred by the movement of people and contaminated equipment.

Clinical signs

NDV affects the gastrointestinal, respiratory and nervous systems and clinical signs reflect the system(s) affected. Clinical signs are usually acute and may appear throughout the flock within 2-12 days. Respiratory signs may include dyspnoea, sneezing, nasal discharge and coughing and are common with low virulence infections.

Newcastle Disease
L. Mahin, Wikimedia Commons

Hosts

Gallinaceous birds, pigeons, parrots, finches

Subclinical carriers: ducks, ostriches

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: 1. 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

2. 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

@@ Line 1: / Line 1: @@
-Newcastle disease is a virus from the family '''Paramyxoviridae'''.  Avian paramyxovirus 1 affects chickens, ducks, pheasants, geese and turkeys.  The virus is stable in carcasses for weeks, so has the potential to affect a large amount of
+{{unfinished}}
+==Description==
+Newcastle disease virus is the causative agent of Newcastle Disease, an acute viral disease of domestic poultry and many other bird species that is usually fatal.
+==Transmission==
+Infected birds shed the virus through droppings and secretions from the nose, mouth and eyes. The virus may also be present in eggs laid during the clinical disease. The virus is commonly transferred by the movement of people and contaminated equipment.
+==Clinical signs==
+NDV affects the gastrointestinal, respiratory and nervous systems and clinical signs reflect the system(s) affected. Clinical signs are usually acute and may appear throughout the flock within 2-12 days. Respiratory signs may include dyspnoea, sneezing, nasal discharge and coughing and are common with low virulence infections.
 [[Image:Newcastle Disease.jpg|150px|thumb|right|''Newcastle Disease'' <br> L. Mahin, Wikimedia Commons]]