Reoviridae

Question 1

Reoviruses are _________ stranded, _________ RNA.

Answer 1

Double stranded, SEGMENTED

Question 2

What kind of symmetry do reoviruses have?

Answer 2

Icosahedral

Question 3

T/F: Reoviruses are enveloped

Answer 3

FALSE

Question 4

T/F: Reoviruses undergo genetic reassortment

What is genetic reassortment?

Answer 4

TRUE

When two different viruses mix and match segments within a shared host to create a new virus

Question 5

Where in the cell do reoviruses replicate?

Answer 5

Cytoplasm

Question 6

T/F: Bluetongue virus is a highly contagious, non infections virus

Answer 6

FALSE

Bluetongue is an infectious, non-contagious virus

Question 7

If you have a patient that you suspect has bluetongue, what should you do?

Answer 7

REPORT IT!!

REPORTABLE / List A virus (transport restrictions)

Question 8

What type of sheep are most commonly susceptible to Bluetongue?

Answer 8

European breeds (fancy wool sheep)

Question 9

T/F: Cattle and goats can contract bluetongue virus

Answer 9

TRUE

symptoms may be less severe

Question 10

How is bluetongue transmitted?

Answer 10

1. Culicoides Sonorensis (most common MOT/Spp of culicoides)
2. Trans-placental
3. Venereal

Question 11

What path does bluetongue virus take once it gets in the body?

Answer 11

Infected by midge –> replicates in vascular and lymph endothelium –> travels to Lungs, LN, and spleen for replication –> viremia

Question 12

T/F: Bluetongue virus may cause lameness in sheep

Answer 12

TRUE - inflammation of the coronary bands is a clinical sign

Question 13

What are some modes of pathogenesis and clinical signs of bluetongue virus?

Answer 13

PATH: Damage to vascular endothelium, necrosis of tissues/organs supplied by damaged arteries, edema, hemorrhage

signs: fever, mucopurulent nasal d/c and crust around nostrils/mouth, buccal and dental pad erosions, cyanotic (blue) tongue*, inflammation of coronary bands, facial edema

Question 14

T/F: Cattle typically get the chronic form of bluetongue

Answer 14

FALSE

acute: congestion and hemorrhage of nose, stomatitis, mucopurulent nasal discharge

Question 15

T/F: There are vaccines available for bluetongue virus

Answer 15

TRUE

Live

Question 16

What is an important form of control for most reoviruses

Answer 16

VECTOR CONTROL

Question 17

What is the mortality rate of African Horse Sickness?

Answer 17

HIGH 75-90%

Question 18

What genus do African Horse Sickness and Bluetongue belong to?

Answer 18

Orbivirus

Question 19

Who gets infected by African Horse Sickness?

Answer 19

Horses-donkeys-mules

*rare occasions - dogs from eating infected meat

Question 20

African horse sickness virus is composed of _____ segments of RNA. There are ____ known serotypes.

Answer 20

10 segments

9 serotypes

Question 21

Who are the vectors for AHS?

Answer 21

Culicoides imicola & C. bolintinos

Question 22

Who is an asymptomatic carrier of AHS?

Answer 22

Zebras

Question 23

What clinical signs are seen in the Dunkup form of AHS and when does it occur?

Answer 23

ACUTE phase

Pulmonary: frothy nasal discharge and froth in trachea, pulmonary edema and petechia of the lungs

Question 24

What clinical signs are seen in the Dikkop form of AHS and when does it occur?

Answer 24

SUBACUTE

Cardiac: edema of the head and eyelids, hydroperitoneum, congestion in conjunctiva, serosal petechia, edema in the mucosa of the colon

Question 25

How do you treat African horse sickness?

Answer 25

CULL Prevention by vector control or vaccine

Question 26

Rotaviruses have _____ segments of ________ stranded RNA. They are broken down into ____ groups (A-H).

Answer 26

11 segments double stranded 8 groups

Question 27

*What group of rotaviruses are he most important cause of diarrhea in young animals and humans?

Answer 27

RVA

Question 28

VP7 are grouped into ____ genotypes. | VP4 are grouped into ____ genotypes.

Answer 28

``` VP7 = G VP4= P ```

Question 29

T/F: Rotaviruses are very stable in the environment

Answer 29

TRUE

Question 30

What is the most common mode of transmission of rotaviruses?

Answer 30

FECAL ORAL ROUTE

Question 31

Where do rotaviruses replicate in the body?

Answer 31

Enterocytes of intestinal vili = malabsorption Dhr | increase calcium in the cell due to replication will also induce secretory dhr

Question 32

``` In what age groups are these animals effected by rotavirus dhr most commonly? Calves Lambs Piglets foals ```

Answer 32

Calves: 1-3 weeks Lambs: less than 3 weeks Piglets: 1-5 weeks foals: anytime?

Question 33

T/F: Rotaviruses are self-limiting

Answer 33

TRUE

Question 34

T/F: If a horse has African horse sickness, you need to report it right away

Answer 34

TRUE - List A virus

Question 35

Is rotavirus zoonotic?

Answer 35

YES!!

Question 36

What are some dx methods used for rotavirus testing?

Answer 36

PAGE, ELISA, Electron microscopy, PCR

Question 37

If you decide to vaccinate for rotavirus, who do you vaccinate?

Answer 37

Horses and cattle - while pregnant so immunity will be passively transferred to the offspring

Question 38

What genus does the avian reovirus belong to?

Answer 38

Orthoreovirus

Question 39

What is the avian reovirus's claim to fame?

Answer 39

Number one cause of lameness in poultry! Causes arthritis and tenosyvitis

Question 40

What are the primary route of transmission of the avian reovirus?

Answer 40

**fecal oral route also transovarial and inhalation

Question 41

What chickens are most effected by avian reovirus?

Answer 41

broilers

Question 42

What is the pathogenesis of avian reovirus?

Answer 42

replication in the intestines --> spread via blood stream to joints --> specifically hock joint --> severe inflammation and synovial fluid - can cause rupture of the gastrocnemius

Question 43

How is the avian reovirus prevented?

Answer 43

Modified and live vaccines Vaccines are admin to layers to pass immunity to chicks sometimes chicks are vaccinated