Newcastle disease

In Great Britain, isolated cases of this disease were first reported in the 1930s. From 1947 outbreaks occurred here over the next 30 years. There were further isolated cases in 1984, 1996-7 and 2005. This disease does however remain a problem world-wide

Birds affected by this disease are:

• Fowl
• Turkeys
• Geese
• Ducks
• Pheasants
• Guinea fowl
• Other wild and captive birds, including ratites e.g. ostriches, emus and rhea

Signs of disease

The clinical signs in affected birds can be very variable. The disease can be present in a very acute form with sudden onset and high mortality or as a mild disease with respiratory distress or a drop in egg production as the only detectable clinical signs. The clinical signs include:

• Depression
• Lack of appetite
• Respiratory distress with beak gaping
• Coughing
• Sneezing
• Snicking, gurgling and rattling
• Yellowish green diarrhoea
• Nervous signs

In laying flocks a sudden drop in egg production with a high proportion of eggs laid with abnormal (soft) shells is often an early sign of disease. Young birds are particularly susceptible and mortality can be heavy, with survivors often exhibiting permanent nervous signs.

Transmission

• Direct contact with secretions from infected birds, especially faeces;
• Contaminated feed, water, equipment and clothing;
• Clinically normal waterfowl and sea birds may introduce the virus into flocks; and
• Broken contaminated eggs may infect chicks in the incubator.