Reoviridae Flashcards
Reoviruses have ____ symmetry
icosahedral
Reoviruses have a triple layer _____
capsid
(outer, middle, and inner layers)
Reoviruses are ____ stranded RNA
double stranded
Reoviruses have a ____genome
segmented
Do Reoviruses have an envelope?
No
Reoviruses replicate in the ____
cytoplasm
Within the cell, reoviruses survive within a ____
vesicle
Reoviruses undergo genetic _____, which is when a single cell is infected by two parent viruses that create progeny that have gene segments from both parents
recombination
When you hear Blue Tongue, what animal should you think of?
sheep!
(and sometimes white tail deer)
____ play a vital role in spread of Blue Tongue because they are the primary reservoir
Cattle
Blue Tongue is a list ___ disease and has serious public health consequences
A
Blue Tongue is caused by Ovine ____
Orbivirus
Blue tongue outer shell is composed of 2 capsid proteins ____ and ____, which determine antigenic differences
VP2 and VP5
How is Blue Tongue transmitted?
Cullicoides variipennis var sonorensis
*biting midge
*trans-placental and veneral play a smaller role
What serotypes of Blue tongue are most common in the US?
2, 10, 11, 13,and 17
Blue tongue causes extensive damage to _____
vascular endothelium
Where does Blue Tongue replicate in the body?
macrohpages and endothelial cells of blood vessels
Blue tongue causes a severe ___ reaction
febrile
What are some common clinical signs of blue tongue in sheep?
edema
nasal discharge
cyanosis of tongue (blue tongue)
Ulceration of oral cavity
Coronitis and Laminitis in feet
Aborted fetuses
Is blue tongue as severe in cattle as it is in sheep?
No, usually less sever or inapparent in cattle
What is the best solution for Blue tongue?
Vaccination
*usually sertype specific
Also, vector control
*insectisides, house animals indoors at night
True/False: African Horse sickness causes high mortality in horses
True
*75-90%
____ sometimes contracts fatal Africal Horse sickenss via ingestion of infected horse meat
dogs
African Horse Sickness is caused by genus _____
Orbivirus
What two proteins of African Horse sickness form the basis of classification of the virus?
VP2
VP5
How is African Horse Sickness transmitted?
Cullicoides Imicola or Cullicoides Bolitinos
What is the reservoir host for African horse sickness?
zebras
What are the clinical findings of acute (pulmonary) african horse sickness?
profuse nasal discharge
petechia of pulmonary pleura
pulmonary edema
frothy fluid in lungs
What are some clinical findings of subacute (cardiac) african horse sickness?
edema of eyelid and muscle
hydropericardium
petechia of apex of cecum (large intestine)
What is the best way to prevent African horse sickness?
Vaccination
Control of vector
*If animals are infected they are normally disposed of to reduce further spread of the virus
What virus is the major cause of viral diarrhea in the young of mammals and birds?
Rotavirus
Rotavirus has a ____ appearance
wheel like
Rotavirus has the ____ protein in the middle layer
VP6
Group ___ Rotavirus are the most common cause of viral diarrhea
A
Rotavirus is classified based on what outer capsid proteins?
VP7
VP4
*Forming the basis of Rotavirus vaccine
What does P1A[8] stand for with Rotavirus?
1A is serotype
8 is the genotype
How is Rotavirus transmitted?
Fecal-oral route
Is rotavirus stable in the environment?
Yes!
very stable
Where in the body does Rotavirus live?
mature enterocytes of small intestine
What does Rotavirus cause damage to?
Villi become damaged and fused
*leading to no absorption
Why is NSP4 important for Rotavirus?
activated phospholipase C
Release of calcium that stimulates nerve endings on endocrine cells
Leads to Diarrhea
What is the main clinical sign of Rotavirus?
Diarrhea
What age group is most susceptible to Rotavirus?
Less than 3-5 weeks old
How can you judge severity of dehydration in Rotavirus?
Check eye to see if sunken in
Skin test- elasticity
What is the most common diagnosis for Rotavirus?
Polyacrylamide Gel Electrophoresis
Are there vaccines for Rotavirus?
vaccines are available but do not work well
*pregnant animals are vaccinated so they can pass down immunity
True/False: Rotavirus is not zoonotic
False!
Rotavirus is zoonotic
Avian Reovirus is caused by what genus?
Orthoreovirus
What does Avian Reovirus cause in chickens?
viral arthritis
Avian Reovirus is primarily a disease of what type of chickens?
Broilers
*meat type
How is Avian Reovirus transmitted?
Fecal oral route
Where does Avian reovirus localize in the chicken?
hock joint
*swollen and inflamed hock joints
What are the best ways to diagnose Reoviruses as a whole?
clinical signs
necropsy
virus isolation
PCR
serological test- ELISA
what is the best treatment for Avian reovirus?
Vaccinate Hen to pass immunity to chicks
*chicks are most susceptible
