LEC 14 - Orbivirus + Rotavirus

Question 1

What is found in a necropsy of an animal who died of Orbivirus?

Answer 1

Ulcers on the tongue

Petechial hemorrhage along the esophagus/trachea

Pulmonary edema +/- CrV pneumonia

Severe hemorrhage in the abdomen

Question 2

What are reoviridae viruses?

Answer 2

Respiratory enteric orphan viruses

Question 3

What does it mean to be an orphan virus?

Answer 3

Researchers do not know if these viruses cause disease or not

Question 4

What are the two groups of reoviridea viruses?

Answer 4

Orbivirus

– and –

Rotavirus

Question 5

What disease does the oribivirus cause?

Answer 5

Epizoonotic hemorrhagic disease

Bluetongue

Question 6

What is the structure of the orbivirus?

Answer 6

Spherical/icosahedral symmetry

Non-enveloped

Question 7

What is the genome structure of orbiviruses?

Answer 7

Segemented dsRNA

Question 8

What is the vector for Orbivirus?

Answer 8

Culicoides

(GNATS)

Question 9

Where does the reoviridea viruses replicate in the host cell?

Answer 9

Cytoplasm

Question 10

What is the sequence of events in reoviridea replication?

Answer 10

Attachment to host receptors+ Endocytosis

Partial uncoating in endolysozomes

Early transcription of genome by viral pol WITHIN VIRAL PARTICLE CYTOPLASM

mRNA segment translation

Aggregation + Encapsidation

Cell death

Question 11

What animals are affected by bluetongue?

Answer 11

Sheep

Question 12

What animals are affected by EHD?

Answer 12

Deer + Sheep

But sheep normally have zero to very little clincal disease

Question 13

What is the host dependent preference of African Horse Sickness?

Answer 13

Horses > Mules > Donkeys

Question 14

What protein is responsible for the serotypes of bluetongue?

Answer 14

VP2

Question 15

What are the major serotypes of EHD? Where are they most commonly found?

Answer 15

EHDV-1: New Jersey

EHDV-2: Alberta

EHDV-6: US

Ibaraki virus: Japan

Question 16

What is different about the way bluetongue presents?

Answer 16

5 to 10 year cycles

Question 17

What is the host preference of EHD?

Answer 17

White tail deer > Mule deer > Elk

Question 18

If you are infected with one serotype of EHD are you protected against other forms?

Answer 18

No, not cross-protective

Question 19

What are the non-edemic bluetongue viruses?

Answer 19

BTV - 1, 4, 8, and 14

Question 20

What are the endemic EHD viruses?

Answer 20

EHDV-1, 2, + 6

Question 21

What is the time of pathogensis in a reoviridae infection?

Answer 21

7 to 10 days

Question 22

How does reoviridae viruses pass through the body?

Answer 22

Blood to bone marrow

Secondary viremia

Endothelial cells

Edema + Hemrrhage + Thrombosis + DIC

Question 23

What are the common clinical signs with Reoviridae viruses?

Answer 23

Fever > 106 deg.

Oronasal discharge

Hypersalivation

Oral necrosis

Coronary band damage + lameness

Question 24

What are the two types of immunity that are induced by a reoviridae infection?

Answer 24

Homologous

– and –

Heterologous

Question 25

What is the homologous immunuity induced by the reoviridae viruses?

Answer 25

Antibody mediated T cell mediated Directed at VP2 + VP5 proteins

Question 26

What is the heterologous immunity induced by a Reoviridae infection?

Answer 26

Directed at NS1 Inner core proteins

Question 27

What are the test used to make a reoviridae diagnosis?

Answer 27

AGID + ELISA = Blood rtPCR

Question 28

What is the treatment for reoviridae infections?

Answer 28

Palliative care Chronic poor doers

Question 29

What time of the year is orbiviral infections most common?

Answer 29

Fall

Question 30

How many serogroups of the rotavirus are there?

Answer 30

7

Question 31

What determines the serogroup of a rotavirus?

Answer 31

VP6

Question 32

What is the structure of the rotavirus?

Answer 32

Non-enveloped

Question 33

What does the rotavirus do to the host cell?

Answer 33

Cytolytic

Question 34

Where does the rotavirus replicate in the host cell?

Answer 34

Cytoplasm

Question 35

What is the structure of the genome of a rotavirus?

Answer 35

dsRNA Segmented

Question 36

How long does it take to see the pathogenesis of rotavirus?

Answer 36

24 hours

Question 37

What is the transmission mechanism of a rotavirus?

Answer 37

Fecal-oral transmission

Question 38

How does rotavirus travel in the body?

Answer 38

GI passage Enterocytes Loss of mature enterocytes at the tips of villi Malabsorption + Secretions

Question 39

How long till clinical signs of a rotavirus infection are seen?

Answer 39

3 to 4 days

Question 40

What are the clincial signs of a rotavirus infection?

Answer 40

Non-bloody +/- watery diarrhea Concurrent infectoins

Question 41

What are the methods used to diagnose a rotavirus infection?

Answer 41

Electron microscopy Serogroup A ELISA/Latex agglutination Fluorescent antibody test

Question 42

What are the preventative measures that can be taken when dealing with rotavirus?

Answer 42

Management changes Oral vaccine

Question 43

What is the treatment for rotavirus?

Answer 43

Supportive Management of concurrent infections

Question 44

How does the reovirus avoid detection by the innate immune system?

Answer 44

Replicating its genome within the viral particle

Question 45

What are the clincial signs of infectious bursal disease virus?

Answer 45

Depends on age 3 to 6 wks = moderate mortality Later = mild infection Depression + Inappetence + Diarrhea

Question 46

What is seen upon histopathology of chickens with IBDV?

Answer 46

Cystic lesions Interfollicular fibrosis Follicular degeneration

Question 47

What type of virus is IBDV?

Answer 47

Birnaviridae

Question 48

What is the genomic structure of IBDV?

Answer 48

dsRNA Linear

Question 49

What is the structure of IBDV?

Answer 49

Non-enveloped

Question 50

Where does IBDV replicate in the host cell?

Answer 50

Cytoplasm

Question 51

What is the sequence of events when it comes to Birnaviridae replication?

Answer 51

Viral penetraion Cytoplasm dsRNA transcription w/i virion +strand translation +strand transcription - strand pairing Budding of mature virons

Question 52

How long does it take for pathogenesis to start with IBDV?

Answer 52

1 to 2 days

Question 53

What is the transmission mechanism of IBDV?

Answer 53

Fecal-oral

Question 54

Where does IBDV target?

Answer 54

GI tissues Liver - Kupfer cells

Question 55

When secondary viremia of IBDV occurs where does it target?

Answer 55

B cells

Question 56

What does it mean when lingering symptoms are seen with IBDV infections?

Answer 56

Immunosuppression

Question 57

What tests can be done to diagnose IBDV?

Answer 57

Gross necropsy ELISA VI rtRNA

Question 58

What is the treatment for IBDV?

Answer 58

Depop/Repopulation Vaccination (MLV + Killed + Recombinant)

Question 59

What sample and test is good for ID'ing a IBDV infection?

Answer 59

Clocal swabs