Birnaviridae Flashcards
Special features of Birnaviridae are:
A. Hexagonal shape, non-enveloped, single-shell
B. Segmented genome (2 segments), one segment designated A and the other B
C. Double-stranded RNA
D. All of the above
Birna= Bi RNA! Double-stranded. Like Reo
Segmented, like Rheo, Orthomyxo, Bunya…
Which of the following is NOT true for Infectious Bursal Disease?
A. It is a disease of young chickens
B. It has affinity for the Bursa of Fabricius
C. Virus is very stable in the environment
D. All serotypes cause serious illness
D
T/F:
Infectious Bursal Disease Serotype 1 contains 3 antigenic subgroups, 2 of which have moderate or high mortality
True
Serotype 2= asymptomatic infections
Infectious Bursal Disease Classic/Standard subgroup has _____mortality, whereas very virulent subgroup has ____ mortality.
A. 10-50; 50-100
B. 0-10; 90-100
C. 0; 100
D. Who cares
B
T/F:
Infectious Bursal Disease will reach the Bursa of Fabricius after primary viremia, and will reach maximal depletion of B-cells here. After secondary viremia, it goes to other lymphoid tissues and induces a cytokine storm
True
T/F:
In the acute phase of Infectious Bursal Disease, the virus will indirectly induce a cytokine storm by activating T-cells and directly by activating Macrophages in lymphoid organs following secondary viremia.
False
Direct activation of cytokine storm= T-cells
Indirect= macrophagees
At day 8 post-infection with Infectious Bursal Disease, you might see: A. Swollen, edematous bursa B. Normal sized bursa C. Atrophied bursa D. Necrotic, destroyed bursa
C.
The mot susceptible age group to Infectious Bursal Disease is:
A. 1-2 days
B. 1 week
C. 6 months
D. 3-6 weeks
D
At day 3 post infection (the acute stage), you are most likely to see: A. Swollen, edematous bursa B. Normal sized bursa C. Atrophied bursa D. Bursa completed necrotic
A
At day 5 is when you will see it go back to normal size
What does it mean for it to be a “hot” strain of IBD used for a vaccine. What is good about it? What is bad?
A. Least attenuated; interferes least with maternal Abs; most chance of resorting to virulence and causing bursal lesions
B. Most attenuated; interferes most with maternal Abs, no virulence possible
C. It is hot because it is an extremely popular vaccine and they can’t keep it on the shelves
D. Hot is also known as Intermediate Plus BTW
E. A and E
E
T/F:
Mild vaccine strains won’t cause bursal lesions but can’t be used until at least 4 weeks of age because they interfere with maternal antibody.
T
T/F:
Two important vaccine types of IBDV are: Immune complex vaccines: IBDV vaccine virus and antibody against the virus inoculated into chicken eggs at day 18 incubation and a vector vaccine using turkey herpes virus to express VP2, an important Birnaviridae protein
True
Yup
