Herpes sp. virus in rabbits
Esther van Praag Ph.D.
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Herpes viruses are common in animals as well as humans, affecting
mainly the respiratory tract and genital organs. They can exist in
subclinical form for long periods, while the bearer remains asymptomatic.
Stress can activate the dormant virus, and cause an outbreak in the infected
rabbit.
There are two Herpes viruses which are specific to
Lagomorphs, and which have been observed in domesticated rabbits:
Herpesvirus
sylvilagus or Hinze Herpesvirus Lymphoma;
Herpesvirus
cuniculi.
Other varieties of the herpes virus, e.g. Herpes simplex,
can be passed from humans to rabbits, and will compromise the rabbit's
health. Rabbits however rarely infect humans with the Herpes virus, which
mainly affects their internal organs, with the notable exception of Herpes
sp. induced keratitis (inflammation of the cornea of the eye).
Rabbits
infected by the virus cannot be cured of it, and so far, no successful
treatment has been reported.
Herpes sylvilagus
This virus is Lagomorph specific. It is transmitted via
fecal matter, urine, the doe's milk, mating, and even through the air. It is
not spread by insects. Herpes sylvilagus
infects mainly the tonsils (a pair of lymphoid tissue masses lying on either
side of the throat). The newly formed viruses are released in the throat
cavity.
Clinical Signs
Common clinical signs include neurological disorders such
as restlessness, circling, seizures, and coma. The development of
interstitial pneumonia (chronic lung disease affecting the tissues between
the cells of the lungs) has additionally been observed in cottontails.
Increased numbers of lymphocytes (lymphocytosis)
in the blood, accompanied by rapidly reproducing lymphoid tissue lesions,
will develop in lymph nodes as well as in other organs (kidneys, liver, lungs
and heart). Experiments in rabbits inoculated with this virus have shown that
tumors can form which are either benign (lymphoid tissue hyperplasia) or
malignant (lymphoma, lymphosarcoma).
Further clinical signs are an increased level of
leukocytes - white blood cells (leukocytosis), and an enlarged spleen (splenomegaly).
Diagnosis
Diagnosis is difficult in living animals. The virus can
be found in the mouth, lymphocytes (white blood cells that fight infection
and disease) and kidneys of the rabbit.
Herpesvirus
cuniculi
This virus has been isolated in colonies of wild rabbits,
and in individuals in a colony of New-Zealand rabbits. Older males which have
become resistant to the virus are thought to be potential carriers,
contributing to its spread.
Clinical Signs
H. cuniculi
causes fever and rashes, with the appearance of small blisters on the skin.
Histological studies have shown mononuclear infiltrates and intranuclear inclusions in the testes, skin, and cornea.
Herpesvirus of unknown origin
An additional, as of yet unidentified, herpes-like virus has
been observed to fatally infect rabbits, causing pneumonia, hemorrhagic
dermatitis, and necrotizing inflammation of the spleen.
Herpes
simplex
There have been reports of naturally occurring cases of Herpes
simplex in domestic rabbits.
Diagnosis is difficult in living animals, and is based on
clinical signs and exposure to humans. Afflicted animals have developed
non-suppurative meningo-encephalitis accompanied by
neuron degeneration, but have not shown exterior macroscopic lesions.
Necropsy and tissue analysis have indicated internal
damage in the temporal and parietal lobes of the brain cortex. The presence
of the virus in the affected tissues has been detected through electronic
microscopy.
For detailed
information on herpes viruses in rabbits, by
E. van Praag, A. Maurer and T. Saarony, 2010,
408 pages. $85.-
Further InformationCebrian
J, Berthelot N, Laithier M. Genome structure of
cottontail rabbit herpesvirus.
J Virol. 1989; 63:523-31.
Cohrs
R, Rouhandeh H. Characterization of the genome of Herpesvirus sylvilagus.
Intervirology. 1987; 28:181-4.
Grest
P, Albicker P, Hoelzle L,
Wild P, Pospischil A. Herpes simplex
encephalitis in a domestic rabbit (Oryctolagus cuniculus).
J Comp Pathol. 2002; 126:308-11.
Heine U, Hinze HC. Morphological studies on Herpesvirus
sylvilagus in rabbit kidney cell cultures. Cancer Res. 1972; 32:1340-50.
Hesselton
RM, Yang WC, Medveczky P, Sullivan JL. Pathogenesis of Herpesvirus sylvilagus infection in cottontail rabbits. Am J Pathol. 1988;
133:639-47.
Hinze
HC. Induction of lymphoid hyperplasia and lymphoma-like
disease in rabbits by Herpesvirus sylvilagus. Int J
Cancer. 1971; 8:514-22.
Kramp
WJ, Medveczky P, Mulder
C, Hinze HC, Sullivan JL. Herpesvirus
sylvilagus infects both B and T lymphocytes in
vivo. J Virol. 1985; 56:60-5.
Mar้
CJ. Viral Diseases. In: The Biology of the
Laboratory rabbit. Weisbroth SH, Flatt RE Kraus AL., Es Academic press, New York, pp.
237-257.
Onderka
DK, Papp-Vid G, Perry AW.
Fatal herpesvirus infection in
commercial rabbits. Can. Vet J. 1992; 33:539-43.
Schmidt SP,
Bates GN, Lewandoski PJ. Probable
herpesvirus infection in an eastern cottontail (Sylvilagus
floridanus). J Wildl Dis. 1992; 28:618-22.
Spieker
JO, Yuill TM. Herpesvirus
sylvilagus in cottontail rabbits: attempted
laboratory transmission by two insect species. J Wildl Dis. 1977; 13:90-3.
Spieker
JO, Yuill TM. Herpesvirus
sylvilagus in cottontail rabbits: evidence of
shedding but not transplacental transmission. J Wildl Dis. 1977; 13:85-9.
Wegner DL, Hinze HC. Virus--host-cell relationship of Herpesvirus sylvilagus
with cottontail rabbit leukocytes. Int J Cancer. 1974; 14:567-75.
Weissenbock
H, Hainfellner JA, Berger J, Kasper I, Budka H. Naturally occurring Herpes simplex encephalitis in
a domestic rabbit (Oryctolagus cuniculus).
Vet Pathol. 1997; 34:44-7.
Yang WC, Hesselton RM, Sullivan JL. Immune responses to Herpesvirus sylvilagus
infection in cottontail rabbits. J Immunol. 1990;
145:1929-33. |
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