avian & livestock assay data sheet
Infectious coryza
Test code:
B0038 - Ultrasensitive qualitative detection of infectious coryza (Avibacterium
paragallinarum bacteria; formerly Hemophilus
paragallinarum) by real time polymerase chain
reaction
B0038 is
included in the poultry
respiratory panel
Infectious
coryza (IC) is an infectious respiratory disease found in many
avian species worldwide. The causative agent of IC is
Avibacterium paragallinarum
(formerly known as Haemophilus paragallinarum).
The disease can be acute to subacute at onset but typically
progresses to a chronic state, with infected birds becoming
carriers of the bacteria. Common names for the disease include
croup, cold and coryza. In the United States, it is predominantly
found in small noncommercial, menagerie, or hobby flocks. While
chickens are the primary host of infectious coryza, pheasants,
guinea fowl and turkeys are also susceptible.
Chronically
ill or inapparent healthy carrier birds are the reservoir of
infection. The source of the disease is often the addition of
carrier birds to the flock. Recovered birds remain carriers and
shedders for life. Transmission occurs by direct bird to bird
contact, inhalation of infectious aerosols coughed into the air,
or by ingestion of contaminated feed and water. The organism can
be transferred on contaminated clothing, equipment and other
fomites.
Coryza
usually occurs in juvenile and mature birds 14 weeks of age or
older. Incubation period is 1 to 3 days and the course of the
acute disease stage is 4 to 12 weeks. Symptoms include nasal
discharge, facial swelling, sneezing, labored breathing and
fetid odor of the exudates. The infection mainly involves the
upper respiratory tract--trachea, sinuses and air passages of
the head.
A.
paragallinarum
bacteria have a polar staining and pleomorphic rod morphology.
The bacterium is non-motile and gram negative. There are three
antigenic types (A, B, and C) which all share certain antigens.
H. paragallinarum requires both “X” and “V” factors in the media
to grow.
Culture
identification has traditionally been used to identify this
bacterium. However, the stringent requirements for sample
handling for culture for this bacterium, long incubation time
and the occurrence of numerous variants of the bacteria have
made culture difficult to perform and not optimally sensitive.
Serological detection of A.
paragallinarum is limited by availability of good
monoclonal antibodies and the sensitivity of the individual
assay protocol. Molecular detection by PCR has been confirmed to
be the most sensitive, specific and rapid way of identifying
this bacterium (Blackall, 1999).
Utilities:
-
Help confirm the disease causing agent
-
Environmental monitoring
-
Help ensure that bird populations are free of
A. paragallinarum
-
Early prevention of spread of this bacterium among bird
populations
-
Minimize human exposure to this bacterium
-
Safety monitoring of biological products and vaccines
that derive from birds
References:
Blackall, P.J. (1999) Infectious Coryza: Overview of the Disease
and New Diagnostic Options. Clin Microbiol Rev. 12: 627–632.
Specimen requirements:
Throat swab or
sinus swab.
Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.
For all
specimen types, if there will be a delay in shipping, or during
very warm weather, refrigerate specimens until shipped and ship
with a cold pack unless more stringent shipping requirements are
specified. Frozen specimens should be shipped so as to remain
frozen in transit. See shipping
instructions for more information.
Turnaround time:
2 business days
Methodology:
Qualitative PCR
Normal range:
Nondetected