Reoviridae Flashcards
Reoviruses are _________ stranded, _________ RNA.
Double stranded, SEGMENTED
What kind of symmetry do reoviruses have?
Icosahedral
T/F: Reoviruses are enveloped
FALSE
T/F: Reoviruses undergo genetic reassortment
What is genetic reassortment?
TRUE
When two different viruses mix and match segments within a shared host to create a new virus
Where in the cell do reoviruses replicate?
Cytoplasm
T/F: Bluetongue virus is a highly contagious, non infections virus
FALSE
Bluetongue is an infectious, non-contagious virus
If you have a patient that you suspect has bluetongue, what should you do?
REPORT IT!!
REPORTABLE / List A virus (transport restrictions)
What type of sheep are most commonly susceptible to Bluetongue?
European breeds (fancy wool sheep)
T/F: Cattle and goats can contract bluetongue virus
TRUE
symptoms may be less severe
How is bluetongue transmitted?
- Culicoides Sonorensis (most common MOT/Spp of culicoides)
- Trans-placental
- Venereal
What path does bluetongue virus take once it gets in the body?
Infected by midge –> replicates in vascular and lymph endothelium –> travels to Lungs, LN, and spleen for replication –> viremia
T/F: Bluetongue virus may cause lameness in sheep
TRUE - inflammation of the coronary bands is a clinical sign
What are some modes of pathogenesis and clinical signs of bluetongue virus?
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
T/F: Cattle typically get the chronic form of bluetongue
FALSE
acute: congestion and hemorrhage of nose, stomatitis, mucopurulent nasal discharge
T/F: There are vaccines available for bluetongue virus
TRUE
Live
What is an important form of control for most reoviruses
VECTOR CONTROL
What is the mortality rate of African Horse Sickness?
HIGH 75-90%
What genus do African Horse Sickness and Bluetongue belong to?
Orbivirus
Who gets infected by African Horse Sickness?
Horses-donkeys-mules
*rare occasions - dogs from eating infected meat
African horse sickness virus is composed of _____ segments of RNA. There are ____ known serotypes.
10 segments
9 serotypes
Who are the vectors for AHS?
Culicoides imicola & C. bolintinos
Who is an asymptomatic carrier of AHS?
Zebras
What clinical signs are seen in the Dunkup form of AHS and when does it occur?
ACUTE phase
Pulmonary: frothy nasal discharge and froth in trachea, pulmonary edema and petechia of the lungs
What clinical signs are seen in the Dikkop form of AHS and when does it occur?
SUBACUTE
Cardiac: edema of the head and eyelids, hydroperitoneum, congestion in conjunctiva, serosal petechia, edema in the mucosa of the colon
How do you treat African horse sickness?
CULL
Prevention by vector control or vaccine
Rotaviruses have _____ segments of ________ stranded RNA. They are broken down into ____ groups (A-H).
11 segments
double stranded
8 groups
*What group of rotaviruses are he most important cause of diarrhea in young animals and humans?
RVA
VP7 are grouped into ____ genotypes.
VP4 are grouped into ____ genotypes.
VP7 = G VP4= P
T/F: Rotaviruses are very stable in the environment
TRUE
What is the most common mode of transmission of rotaviruses?
FECAL ORAL ROUTE
Where do rotaviruses replicate in the body?
Enterocytes of intestinal vili = malabsorption Dhr
increase calcium in the cell due to replication will also induce secretory dhr
In what age groups are these animals effected by rotavirus dhr most commonly? Calves Lambs Piglets foals
Calves: 1-3 weeks
Lambs: less than 3 weeks
Piglets: 1-5 weeks
foals: anytime?
T/F: Rotaviruses are self-limiting
TRUE
T/F: If a horse has African horse sickness, you need to report it right away
TRUE - List A virus
Is rotavirus zoonotic?
YES!!
What are some dx methods used for rotavirus testing?
PAGE, ELISA, Electron microscopy, PCR
If you decide to vaccinate for rotavirus, who do you vaccinate?
Horses and cattle - while pregnant so immunity will be passively transferred to the offspring
What genus does the avian reovirus belong to?
Orthoreovirus
What is the avian reovirus’s claim to fame?
Number one cause of lameness in poultry!
Causes arthritis and tenosyvitis
What are the primary route of transmission of the avian reovirus?
**fecal oral route
also transovarial and inhalation
What chickens are most effected by avian reovirus?
broilers
What is the pathogenesis of avian reovirus?
replication in the intestines –> spread via blood stream to joints –> specifically hock joint –> severe inflammation and synovial fluid - can cause rupture of the gastrocnemius
How is the avian reovirus prevented?
Modified and live vaccines
Vaccines are admin to layers to pass immunity to chicks
sometimes chicks are vaccinated
