Introduction

A herpesvirus infection of ducks and geese diagnosed in the UK in 1972, mostly in ornamental collections, in USA since 1967, also the Netherlands and other countries.

All waterfowl are susceptible and the Barbary duck is more susceptible than the Pekin. The disease follows a very acute course with a morbidity of 5-100% and mortality of 5-100%. Transmission is by infected birds, fomites and arthropods. Recovered birds may carry the virus for a year.

Signs

• Sudden deaths.
• Rapidly spreading disease.
• Drop egg production.
• Photophobia.
• Ataxia.
• Closed eyes.
• Thirst.
• Severe diarrhoea, sometimes dysentery.
• Dehydration.
• Paresis.
• Tremor.
• Occasionally penile prolapse in the penis in drakes.
• Occasionally cyanosis of the bill in the young.

Post-mortem lesions

• Severe enteritis.
• Crusty plaques from oesophagus to bursa (covered by yellowish plaques in later stages).
• Haemorrhage in intestine, body cavities, heart, pericardium, liver, spleen.
• Young ducks may show thymic and bursal lesions.

Diagnosis

Isolation: Duck CAMs 12 day embryos die in 4 days, HA-, intranuclear inclusions Differentiate from Duck hepatitis, oesophagitis (birds on restricted feed), vent gleet, pasteurellosis, coccidiosis.

Treatment

None, but vaccination in face of outbreak is of value, probably through interference.

Prevention

Isolation from waterfowl, vaccination if approved by authorities (CE adapted live virus).