Viral Diseases of Reptiles Flashcards
what is Inclusion Body Disease (IBD) of Boid Snakes
- Boa constrictors and several species of pythons are most commonly affected
- caused by a retrovirus but recently an arenavirus
- Boas - host becoz so many are infected, and they can harbor the virus for years with few to no clinical signs.
signs of Inclusion Body Disease (IBD) of Boid Snakes
a history of unthriftiness, anorexia, weight loss, secondary bacterial infections, poor wound healing, dermal necrosis, and regurgitation.
what kind of Dse?
As the disease becomes chronic, some boas exhibit neurologic symptoms ranging from mild facial tics and abnormal tongue flicking to failure of the snake to right itself when placed in dorsal recumbency and severe seizures.
Inclusion Body Disease (IBD) of Boid Snakes
findings in the acute phase of this disease include leukocytosis and a normal chemistry panel
Inclusion Body Disease (IBD) of Boid Snakes
____are thought to be a more abnormal host for the IBD virus, because the course of disease is more acute and neurologic symptoms more profound.
Pythons -present with severe neurologic disease
*the active disease can linger for months or more in boas, most pythons die within days or weeks of the onset of clinical signs.
common ways of transfer retrovirus/arenavirus
Breeding, fight wounds, fecal/oral contamination, and snake mites
*Exposure to this due to a transfer of body fluids.
A tentative diagnosis in IBD is based on
history and clinical signs
*On blood smears, inclusion bodies are frequently found in the cytoplasm of leukocytes
A definitive diagnosis in IBD is obtained via
biopsy of internal tissues
*eosinophilic inclusion bodies are found, eg, the liver, kidney, esophageal tonsils, and stomach.
tx for IBD
- not curable
- owners choose euthanasia
- may elect to isolate their snakes and treat with supportive and palliative measures
- essential to educate owners not to sell infected specimens or their offspring, because this has caused the disease to spread worldwide
also been found in Russell vipers, corn snakes, and California kingsnakes
*Retroviruses
designated as viper virus?
retrovirus isolated from a sarcoma in a Russell viper
designated cornsnake retrovirus
isolated in a corn snake from a rhabdomyosarcoma
have been implicated in fatal hepatic or GI diseases in
snakes (gaboon vipers, ball pythons, boa constrictors, rosy boas, and rat snakes),
lizards (Jackson chameleons, savannah monitors, and bearded dragons) and
crocodilians.
. Adenoviruses
Adeno virus route of transmission in bearded dragons
fecal/oral contamination.
vague and more commonly noted in juvenile dragons
CS include lethargy, weakness, weight loss, diarrhea, and sudden death
Adenoviruses
*morbidity is high in young bearded dragons
treatment of adenovirus in bearded dragons?
Fluid administration, force feeding, and antibiotics for secondary infections are useful.
why we need to confirm diagnosis of Adeno virus in bearded dragons
because it is vague and similar to those caused by coccidia and nutritional disorders
in adeno virus : where to find a Characteristic intranuclear inclusion bodies
found in several internal organs, primarily the liver.
other ways to dx Aden virus
- group lizard -sacrifice a failing specimen
- liver biopsy
- ID from fresh feces
Management of reptiles when recovered in Adeno virus dse
- lizards quarantined for at least 3 mo
* Duration of viral shedding after recovery is unknown
have been isolated from freshwater turtles, tortoises, and green sea turtles
. Herpesviruses
In freshwater turtles, herpesvirus may be associated with_____
hepatic necrosis
In tortoises, the herpes virus may cause ______
necrosis of oral mucosa accompanied by anorexia, regurgitation, and oral and ocular discharge.
tx and dx of herpes virus in tortoises
isolation, supportive care, and application of 5% acyclovir to oral lesions (improve the lesions in a desert tortoise)
*diagnosed by the presence of intranuclear inclusion bodies and electron microscopic demonstration of viral particles.
Herpesvirus infection of farmed green sea turtles have been associated with what?
(1)gray patch disease and (2)lung-eye-trachea disease (3)fibropapillomas plague certain free-ranging populations, especially around Hawaii.
causes epizootics of small, circular papular skin lesions that coalesce into patches and is associated with young turtles maintained in crowded, warmer, stressful situations
Gray patch disease (chelonian herpesvirus 1)
in Gray patch disease Biopsies of the skin reveal ?
basophilic intranuclear inclusion bodies in epidermal cells;
viral particles - in the cytoplasm by electron microscopy.
treatment in Gray patch disease
- no specific treatment
* reduction of crowding and stress appears to decrease the incidence.
causes harsh respiratory sounds, with ulcerations and caseous debris over the globe and throughout the oropharynx and trachea
Lung-eye-trachea disease
Buoyancy problems and high mortality are reported in this kind of disease
Lung-eye-trachea disease
*route of transmission is not known
*with light gray to black masses to 20 cm in diameter.
*
Fibropapillomatosis
- location of the masses dictate the severity of signs.
- masses primarily in the lungs, liver, kidneys, and GI tract.
tx in Fibropapillomatosis
- surgical removal, with wide margins to help reduce recurrence.
- Infected should; isolate
- are highly contagious virus
- more common in viperid snakes
- but been reported in nonvenomous snakes as well
. Paramyxovirus
- respiratory signs
- transmission - respiratory secretions
- Secondary bacterial infections are common common because of the severe inflammation initiated by the virus
- open-mouth breathing, caseated pus in the oral cavity, and labored breathing.
- Neurologic involvement, including tremors and opisthotonos,
Paramyxovirus
how to detect viral particles of Paramyxo?
Endoscopic biopsies and postmortem samples of lung by histology and electron microscopy.
test available to measure antibodies against ophidian paramyxovirus
A hemagglutination inhibition test
used as a screening tool to help eliminate infected animals and prevent carriers from entering noninfected collections in paramyxovirus
a positive titer
*has resulted in epizootic outbreaks in farmed alligators,
West Nile Virus
clinical signs of west nile
- multiorgan necrosis
- heterophilic granulomas,
- heterophilic perivasculitis
- lymphoplasmacytic mengingoencephalitis
- Very high viremia titers in reptiles
may play a role as an amplification host in of westniile virus
reptiles
particles appear to be transmitted from one European green lizard to another via bite wounds
*are 2–20 mm in diameter and may be single or multiple.
. Papillomas
tx for Papillomas
- surgical removal of single masses,regrowth is common
* Isolation of affected lizards -prevent spread
A papilloma-type virus also appears to affect ___
Bolivian side-neck turtles
appears as white, oval skin lesions distributed over the head
- Ulcerative shell lesions -(plastron)
- TX: is supportive and palliative
A papilloma-type virus on Bolivian side-neck turtles
- reported in various chelonians, snakes, and lizards.
* found in a Hermann’s tortoise, which died without prior signs of disease
Iridoviruses
- cause Progressive anemia in Australian geckos
* range from none to stomatitis, rhinitis, conjunctivitis, tracheitis, edema, and cutaneous abscessation.
. Iridoviruses
- the recovered iridoviruses have been closely related to
* , iridoviruses deserve close attention, especially in chelonians.
amphibian ranaviruses
Two nonpathogenic rhabdoviruses were isolated from?
Ameivasp lizards.
virus found in the intestinal tract of snakes, but their exact role is unknown
herpesviruses, adenoviruses, parvoviruses and picornaviruses
has been isolated from circumscribed cutaneous lesions ina caiman and from dermal lesions in ategu.
poxvirus-like virus
A reovirus isolated from ____was associated with death without prior signs of illness.
Chinese vipers
