Newcastle disease

A recent press release, July 25th, on the APHA website assesses the risk that the recent cases of Newcastle disease, in commercial poultry (1 case) and hobby flocks in Belgium (12 cases, see table 1) and Luxembourg (1 case) poses for the UK. The conclusion is that the risk has increased. Therefore, the risk of Newcastle disease to UK commercial poultry and hobby flocks has been raised from Low to Medium.

(https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/726520/poa-newcastle-disease-belgium-180717.pdf)

Newcastle disease is a viral infection caused by avian avulavirus type 1 (formerly Avian Paramyxovirus-1). This virus can infect many species of birds and varies in its ability to cause clinical disease from strains that infect chickens causing no clinical signs to strains that can kill within 24 hours. These latter strains are known as velogenic or highly virulent Newcastle disease. It is these strains that have been found in 12 hobby flocks and 1 commercial flock of poultry in Belgium.

The clinical signs and incubation period have been summarised in table 2. Based on clinical signs, it is very difficult to distinguish Newcastle disease from Avian Influenza.

The strain of virus isolated from these Belgian flocks is closely related to viruses that have been associated with outbreaks, primarily in backyard flocks, in Bulgaria, Romania and the Republic of Cyprus. This virus is derived from strains circulating in the Middle East and Central Asia and is believed to have been spread by human activity rather than wild birds.

It is surmised that the current widespread distribution of cases in Belgium is possibly associated with a dealer or market source.

How can you protect your flock from Newcastle disease?

  1. Ensure that all purchases of poultry or eggs either directly or over the internet from the EU have the appropriate import / export certificates and TRACES documentation. Purchasing half a dozen hatching eggs or bringing a few live poultry back from the EU without the correct documentation is illegal and shows a selfish disregard for other poultry keepers. For further details go to https://www.gov.uk/guidance/moving-live-animals-or-animal-products-as-part-of-eu-trade
  2. You can vaccinate your poultry against Newcastle disease. The vaccination programme should include two live vaccinations in rear followed by an inactivated vaccination prior to point of lay.

When done properly this will protect your birds from clinical signs for up to a year in lay. It will not protect from infection and it does not give life long immunity. All birds in your flock should be revaccinated annually.

  1. All the biosecurity measures that you have in place to minimise the likelihood of getting Avian Influenza will be equally effective for Newcastle disease. Make sure you do not let them lapse.

 

Table 1 Newcastle disease in captive and commercial birds in Belgium 2018

Date confirmed Area Holding Comment
26/04/2018 Herstal Hobby 12out of 20 birds died over 18 days
14/06/2018 Kessel Hobby 29 chickens
14/06/2018 Soignies Hobby 45 chickens, 40 guinea fowl
15/06/2018 Verviers Hobby 17 chickens
22/06/2018 Villers-la-Ville Hobby 13 chickens
25/06/2018 Theux Hobby/pet shop 73 ducks, 10 geese. 1 partridge, 175 chickens, 6 pigeons no clinical signs
25/06/2018 Dentergem Hobby 5 chickens
25/06/2018 Helecine Hobby 31 chickens
27/06/2018 Zoutleeuw Hobby / small dealer 130 chickens
27/06/2018 Erpe-Mere Hobby 160 chickens
04/07/2018 Haaltert Dealer Hobby chickens 3,648 birds all kinds of poultry and species, no clinical signs
06/07/2018 Morlanwelz Hobby 121 chickens
07/07/2018 Zulte Commercial layers 57,820 hens
References accessed 29/7/18
https://ec.europa.eu/food/sites/food/files/animals/docs/reg-com_ahw_20180613_pres_newcastle-disease_bel.pdf
https://ec.europa.eu/food/sites/food/files/animals/docs/reg-com_ahw_20180712_pres_nd_bel.pdf
 

 

 

 

Table 2 – Newcastle disease: age, incubation period and clinical signs

Age Younger birds generally more susceptible than adults.
Incubation 4-6 days (2 – 15d); virus shed during incubation
Signs These will vary with the species of bird, previous vaccination and any other exacerbating conditions.

– General: high mortality and morbidity depression, inappetent,

– Respiratory: beak gaping, gasping, coughing, gurgling, rattling, swelling of the tissues around the eyes and in the neck.

– Nervous: drooping wings, dragging legs, twisting of the head and neck, circling, complete paralysis, apparent blindness

– Digestive: greenish watery diarrhoea.

– Reproduction: partial or complete cessation of egg production, misshapen eggs, rough-shelled, loss of shell colour, thin-shelled and contain watery albumen.