avian & livestock assay data sheet
Swine vesicular disease (SVD)
NOTE: THIS TEST IS
NOT PERFORMED ON SAMPLES TAKEN FROM ANIMALS
OWNED OR LOCATED IN THE STATE OF CALIFORNIA.
Test code:
S0125
-
Ultrasensitive detection of swine vesicular
disease virus by reverse transcription coupled
real time PCR
Swine vesicular disease virus (SVDV) is a
porcine enterovirus in the family picornaviridae.
It is antigenically related to the human
enterovirus Coxsackie B-5 but is unrelated to
other known porcine enteroviruses.
Pigs are the only species naturally infected,
but laboratory personnel have been infected due
to occupational exposure.
Pigs infected with this virus show almost
identical clinical signs to foot-and-mouth
disease (FMD) in pigs. The clinical signs
include fever, salivation and lameness. Vesicles
and erosions can be seen on the snout, mammary
glands, coronary band, and interdigital areas.
Vesicles in the oral cavity are relatively rare.
The infection may be subclinical, mild, or
severe depending on the virulence of the strain.
Severe signs are generally seen only in pigs
LOCATED on damp concrete. Younger animals can be
more severely affected. Neurologic signs due to
encephalitis, such as shivering, unsteady gait,
and chorea (rhythmic jerking) of the legs, are
rare. Abortion is not typically seen. Recovery
occurs within 2 to 3 weeks, usually with little
permanent damage.
Transmission of the virus can occur by ingestion
of contaminated meat scraps or contact with
infected animals or their feces. Pigs can
excrete the virus from the nose, mouth, and in
feces up to 48 hours before clinical signs are
seen. Virus can be shed in the feces for up to
three months following infection. Furthermore,
SVDV can survive for long periods of time in the
environment; it is resistant to heat up to 69°C
(157°F) and pH ranging from 2.5 to 12. It can
also survive up to two years in lymphoid tissue
contained in dried, salted, or smoked meat.
Swine vesicular disease is considered to be
moderately contagious. Compared to FMD,
morbidity is lower and the lesions are less
severe. Mortality is not generally a concern
with swine vesicular disease.
Although neither disease is currently present in
North America, differentiation of these two
vesicular diseases is still important because
the introduction of FMD could cause severe
economic losses.
Swine vesicular disease or other vesicular
diseases should be suspected when vesicles or
erosions are found on the snout and/or feet of
pigs. Differentials for swine vesicular disease
include FMD, vesicular stomatitis, vesicular
exanthema of swine, and chemical or thermal
burns. In swine vesicular disease outbreaks,
pigs will be the only species affected, the
lesions will be mild, and there will be no
mortality. Other vesicular diseases must be
ruled out with laboratory tests.
SVDV can be identified using enzyme-linked
immunosorbent assay (ELISA), the direct
complement fixation test, and virus isolation in
pig-derived cell cultures. Virus neutralization
and ELISA can be used for serological diagnosis.
However, all these methods are relatively
nonspecific and are labor intensive to perform.
Molecular detection by PCR can enable rapid,
specific and sensitive characterization of the
virus (Ferris et al., 2006; Reid et al. 2004).
Utilities:
-
Help confirm the disease causing agent
-
Identify SVDV virus carriers
-
Help ensure that animal colonies and populations are free of
SVDV
-
Early prevention of spread of the virus among animals
-
Minimize human exposure to the virus
-
Safety monitoring of biological products that derive
from animals
References:
Ferris, N.P., King, D.P., Reid, S.M., Hutchings,
G.H., Shaw, A.E., Paton, D.J., Goris, N., Haas,
B., Hoffmann, B., Brocchi, E., Bugnetti, M.,
Dekker, A. and De Clercq, K. (2006)
Foot-and-mouth disease virus: a first
inter-laboratory comparison trial to evaluate
virus isolation and RT-PCR detection methods.
Vet Microbiol. 117:130-40.
Reid, S.M., Paton, D.J., Wilsden, G., Hutchings,
G.H., King, D.P., Ferris, N.P. and Alexandersen,
S. (2004) Use of automated real-time reverse
transcription-polymerase chain reaction (RT-PCR)
to monitor experimental swine vesicular disease
virus infection in pigs. J. Comp. Pathol.
131:308-17.
Specimen requirements:
Vesicular fluid or lesion swab, or 0.2 ml whole
blood in EDTA (purple top) tube, or 0.2 ml feces, or 0.2 ml fresh or frozen
tissue.
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 reverse transcription coupled real
time PCR
Normal range:
Nondetected
|