Newcastle Disease

Description

Newcastle disease is a highly contagious, generalised viral disease of domestic poultry, cage and aviary birds, and wild birds. Clinical history of Newcastle disease could include sudden change in health, production and mortality. Clinical signs of virulent Newcastle disease in affected poultry include severe depression, sudden drop in egg production, respiratory disease, nervous signs such as paralysis, torticollis, tremors of the head and unsteady gait, diarrhoea, and rapidly escalating and continuing deaths. The recent Australian cases were predominantly characterised by nervous signs and/or respiratory disease.

Low pathogenicity strains of Newcastle disease have been circulating in Australian wild birds and poultry since at least 1960s. Initially, these were not associated with any clinical disease. The significant outbreaks of Newcastle disease in chickens in late 1990s/ early 2000s were due to locally derived strains that had become pathogenic; these were distinct viruses from those present in wild birds.

Vaccination of commercial poultry is compulsory in NSW. Either killed vaccine, or live avirulent V4 strain in which case some birds will remain carriers.

Differential diagnoses include acute fowl cholera, respiratory disease complex and other exotic diseases such as avian influenza.

Pigeon paramyxovirus is closely related to, but different from, Newcastle disease.

Diagnosis and tests available

Diagnosis

A diagnosis of virulent Newcastle disease is suggested by high mortality in poultry with confirmation by real-time PCR.

Tests available

Test

Sample(s) required

Days of the week test is conducted

Turnaround time1

Newcastle disease real time PCR

Swab(s) in PBGS or fresh tissue

According to demand

Same day-3 days2

Newcastle disease virus HI

Clotted blood (red top tube)

According to demand

Up to 1 week

1 Turnaround times are provided as a guide only. For specific information about your submission please contact Customer Service.
2 Turnaround time depends on urgency.

Specimen requirements

Blood (without anti-coagulant)

  • 10 ml of blood (including at least 0.5 ml serum) collected into a plain red top tube
    • Submit chilled

Fresh tissue

  • Spleen, lung, kidney, heart, liver and bone marrow
    • Submit chilled
    • Fresh tissues should be in separate containers and labelled to identify bird and tissue sampled
    • Portions should be about 1 cm cubes

Swab

  • Separate cloacal and tracheal swabs (not pharyngeal) should be submitted in viral transport media (PBGS) and with clear labels to identify bird and tissue sampled.
    • Use sterile swabs
    • Paediatric swabs can be used for small birds
    • Submit chilled
  • Dead birds securely packed (i.e double bagged and in a rigid container that is clearly labelled as suspect Newcastle disease) can be submitted and swabbed at the laboratory. The carcass will be put on hold for further testing pending results.
    • Live birds should not be submitted
    • If not considered a genuine case of exotic disease exclusion, the submitter may be charged for a more detailed necropsy

Further information

Note

  • Fees for tests undertaken to confirm or exclude a diagnosis of Newcastle Disease are paid by NSW Department of Primary Industries. Extra testing to establish an alternative diagnosis is at submitters’ expense
  • Always clearly label specimens as Suspect Newcastle disease. Pack securely and forward separately from any other specimens.
  • Advise the laboratory Customer Services of your submission and place a warning under the lid of the outer packaging.This will ensure specific biosecurity precautions are undertaken at the laboratory.