Cardiovascular Block Lecture 9

Bluetongue virus causes what ?

a systemic vascular disease, with clinical illness most evident in susceptible sheep and some wild ruminants.

With Bluetongue in ruminants: Vascular damage explains what

edema, hemorrhage and tissue injury.

can we use Clinical appearance alone for Bluetongue in ruminants

Clinical appearance alone cannot confirm the cause.

How is EVA and bluetongue virus in ruminants similar

they are similar becayse they cause leakage and edema

How does bluetongue virus gets its name

it gets its name from because it will cause edema or hemorrhage or infect the vascular endothelial cells and cause cyanosis

• can also cause lameness

In cattle do they show obvious signs of bluetongue virus

• no cattle will have subclunical infection

What is the genoe for Sedoreoviridae

10 segments of dsRNA

• the 10 means has multiple layers

• we should worry because of antigenic shift

Is their envelope present for Sedoreoviridae

• its absent

• non enveloped

• need specific detergent to kill it

What baltimore group is Sedoreoviridae

Balitmore 3

Where does Sedoreoviridae replicate

in the cytoplasm

The capsid layer is VP2/VP5 where do we find them?

the outside layer

The capsid layer is VP7 where do we find them?

in the core surface

The capsid layer is VP3 where do we find them?

subcore

What are Orbiviruses

are vector-borne pathogens transmitted between vertebrate hosts by vectors such as mosquitoes, midges, and ticks.

What is the role for VP2 surface protein

cell attachment and the main target of serotype-specific neutralizing antibodies.

What is the role of VP5 protein surface

membrane penetration during entry.

What is the role of VP7 and VP3 protein surface

structural layers that protect the genome.

What is the role for VP1

RNA-dependent RNA polymerase within the core.

How many serotypes are their for BTV

There are at least 29 recognized serotypes of the bluetongue virus (BTV) worldwide.

What do we mean by mechanical vector

the vector will carry the viral particle without replication

What do we mean by biological vectors

viral particles that replicate inside the vector

What is the biological vector for BTV

Culicoides biting midges

How does Culicoides biting midges acquire BTV

They acquire BTV while feeding on an infected ruminant and can later transmit it during feeding.

The 24 classical serotypes,(_____), are transmitted primarily by primarily by Culicoides biting midges.

BTV-1–24

What are other factors that influence BTV

Vector activity, temperature and local habitat influence the season and geography of disease.

Which animal may have prolonged viremia with few signs, helping maintain the local cycle.

Cattle

For BTV Direct contact transmission occurs

with some atypical BTV strains.

Some strains cross the placenta and may cause what

fetal loss or congenital abnormalities.

Can male ruminants carry BTV ?

• Semen from an infected, viremic male may transmit BTV.

• Risk depends on the strain and stage of infection.

Can blood contamined equipment transfer BTV

yes it can

Infection of hematopoietic and endothelial cells contributes to

microvascular damage.

The vascualr change is Increased permeability what are the clinical consquences

Facial, oral and pulmonary edema

The vascular change is Endothelial injury and hemorrhage what are the clinical consequences

Petechiae and larger hemorrhages

The vascular change is Thrombosis and impaired perfusion what are the clinical consquences

Tissue necrosis and epithelial sloughing

What clinical signs can share one vascular basis

Oral lesions, respiratory compromise and lameness

The host is the sheep what are the Typical clinical pattern

• Overt disease is common in susceptible sheep

• Severity ranges from mild illness to death.

The host is Cattle and goats what are the Typical clinical pattern

• Usually subclinical.

• Some strainscause severe disease or reproductive losses.

THe host is Cervids what are the Typical clinical pattern

Some species develop acute hemorrhagic disease or sudden death.

The host is Other mammals what are the Typical clinical pattern

• Rare clinical cases occur in camelids and pregnant dogs

• Susceptibility varies.

Is BTV zoonotic

no its not

What are the clinical findings in sheep for BTV

• depression

• reduced intake

• reluctance to move

• facial/oral edema

• salication

• painful oral erosions

• lamness

• tachypnea

• dyspnea

• reproductive loss (abortion_

A severely swollen tongue may become cyanotic and protrude, but a blue

tongue is not required for

clinical suspicion.

The test is RT-PCR what does it detect and what is the interpretation

• BTV RNA

• Supports infection.

• A positive result alone does not prove infectious virus.

The test is Virus isolation what does it detect and what is the Interpretation

• Viable BTV

• Demonstrates recoverable infectious virus.

• A negative result may not exclude infection.

The test Competitive ELISA what does it detect and how do we interpret it

• BTV antibodies

• Shows an immune response.

• Interpret with infection and vaccination history.

The test is Virus neutralization what does it detect and what is the interpreation

• Neutralizing antibodies

• Helps assess the serotype-specific antibody response

Early infection can be what

seronegative.

Is their cure for BTV?

• There is no specific curative antiviral for routine BTV care.

• Supportive treatment!

• Provide soft feed, accessible water, and shelter.

• Manage pain appropriately.

• Fluid therapy when vascular leakage or pulmonary edema complicates hydration.

Antibiotics treat secondary bacterial disease, not what

BTV itself.

Is there a vaccine for BTV

BTV-10 Modified Live Virus (MLV): Manufactured by the Colorado Serum Company, this is the only USDA-licensed vaccine.

The commercially available U.S. vaccines are

serotype-specific.

Should we give cattle the BTV-10 Modified Live Virus (MLV)

In the U.S., cattle vaccination is not routine. Decisions depend on authorized products, disease risk, and surveillance or trade requirements. Vaccines can complicate serological differentiation of infection from vaccination.