Family: Bornaviridae Flashcards
Borna = _______
village in Germany
What is the structure of the Bornaviridae virion? What is its genome like? Where does it replicate?
spherical, enveloped with an inner core
linear, non-segmented negative-sense ssRNA
nucleus
What is Borna disease? How does it affect cell cultures?
devastating epidemics of naturally occurring, infectious, usually fatal, neurological disease in horses
noncytolytic and persistent infection
Bornaviridae characteristics:
How is the genome of Bornaviridae set up?
3’ to 5’
N (nucleocapsid), P, M, G (glycoprotein), L (RdRp)
What disease for Bornaviridae cause? When is mortality high?
sad horse disease - infectious neurological syndrome of warm-blooded animals caused by Borna disease viruses 1 and 2 (BoDV-1/2)
in horses that develop neurological manifestations
Where does Borna viruses 1 and 2 replicate? Why aren’t humoral and cell-mediated immunity helpful with eradication?
principally gray matter neurons and glial cells (polioencephalomyelitis) with persistent infection
- antibodies are non-neutralizing and do not contribute to disease pathogenesis
- stimulated T-cell mediated immunopathologic reaction (delayed hypersensitivity) contributes to disease progression
What is characteristically seen on histology with Borna virus 1/2 infection?
- extensive perivascular cuffing with lymphocytes, macrophages, and plasma cells WITHOUT necrosis
- eosinophilic intranuclear inclusions in neurons: Joest-Degen bodies (pathognomonic)
What does Avian Borna virus (ABV) cause? What is the classical signs? How is it diagnosed?
proventricular dilatation disease (Macaw Wasting Disease)- producing a non-supperative ganglioneuritis in the GI tract and CNS
regurgitation of a mucus-like fluid
physical exam - birds lose weight, making the keel bone palpable and prominent from the breast
How is Avian Borna virus (ABV) transmitted? What are the most common nervous and GIT signs?
fecal-oral, airborne, vertical transmission
NERVOUS: ataxia, blindness, abnormal head, serizures
GIT: undigested food, diarrhea, weight loss, starvation, enlarged proventriculus
What provides the best samples for diagnosing Macaw Wasting Disease? What other samples can be taken?
(Avian Borna virus)
chest or breast contour feathers
- brain tissue
- proventricular tissue
- crop tissue
Why is Avian Borna virus (ABV) commonly classified with poliovirus, herpesvirus, and rabies?
can infect nerve cells
A = perivascular mononuclear infiltrate in the brain
B = perivascular mononuclear infiltrate in the proventriculus
C = mononuclear infiltrate in and around ganglia
How does Borna disease virus (BDV) affect cats?
staggering disease - ataxia, behavioral changes, and loss of postural reactions with non-suppurative encephalomyelitis
How was Borna disease virus (BDV) from a cat with staggering disease isolated? How can disease be diagnosed?
virus was isolated and grew only in embryonic mink brain cells
BDV-specific antigen in CNS samples by IHC and ELISA
