Infectious Coryza Found in Hobby Flocks

UK - The Veterinary Laboratories Agency (VLA) has confirmed two separate cases of infectious coryza in hobby flocks in southern England, and warn vets to be on the look-out for other cases.

14 December 2010

3 minute read

Europe

Infectious coryza (IC) is a respiratory disease of poultry, mainly chickens. It is a bacterial diseaase caused by Avibacterium paragallinarum, formerly known as Haemophilus paragallinarum. It is not known to be zoonotic and therefore there is no known risk to public health.

The disease is of economic importance to the poultry industry in many parts of the world such as Asia, the Americas and parts of Africa. It is also present in continental Europe.

Clinical signs

The disease is characterised in chickens by acute respiratory signs, often with swelling of the face and nasal discharge. There is usually high morbidity and low mortality.

Other clinical presentations may be seen when infection is complicated by the presence of other viral or bacterial pathogens which can alter the clinical presentation and affect severity, and complicate the diagnosis.

The effects of the disease are also known to be more severe in mult-age flocks when younger, non-immune birds come into contact with recovered older birds.

There may also be losses in production including reduced growth in broilers and a drop in egg production in layers.

Disease control

In the short term, IC has been controlled by antibiotic medication in the affected flocks. At present, authorisation from the Veterinary Medicines Directorate is required for the importation of infectious coryza vaccines.

VLA investigation

Following scanning surveillance investigations by VLA regional laboratories, IC has been confirmed by bacteriological and PCR testing in two separate hobby flocks in southern England.

Infection is likely to have been introduced to the flocks via the purchase of infected chickens carrying the organism. The original source of infection is unknown.

Veterinarians should consider infectious coryza during the diagnosis of upper respiratory tract disease, especially in chickens. Please report any suspected cases to a Veterinary Investigation Officer (VIO) at your local VLA regional laboratory.

Reference

Welchman D. de B. et al., 2010. Infectious coryza in chickens in Great Britain. Veterinary Record, 167: 912-913. doi:10.1136/vr.c6841. [click here; fee may be payable].