Notifiable Neuro Viruses

Question 1

Name 5 notifiable viruses (7)

Answer 1

• Rabies
• West Nile Virus
• Equine Viral encephalomyelitis
• Aujesky’s
• Teschen Disease
• Classical Swine Fever
• (BSE/scrapie)

Question 2

What does the image show?

Answer 2

Rabies

Question 3

Wha is the genus of rabies?

Answer 3

Lyssavirus

Question 4

Where are the following animal found with genotype 1 classic rabies:

A) Fox?

B) Dog?

C) Bat?

D) Raccoon?

E) Skunk?

Answer 4

A) West Europe

B) Misse eat, Africa, East Europe

C) North and South Amercia

D) North America

E) North America

Question 5

What are the altered bahviours associated with rabies?

Answer 5

Furious form: Dogs, Cats

• Restlessness, anxiety
• Loss of fear of humans
• Aggression, biting
• Hyperaesthesia

Dumb form: Cattle, Sheep, Horses, Dogs, Cats

• Salivation, Dysphagia
• Depression
• Paralysis: limb, neck, head

Question 6

How can we diagnose rabies?

Answer 6

History and Clinical Signs

Isolation of suspect case (or animal from endemic area that has bitten a human)

Histopathology of CNS tissue

–Demonstration of inclusion bodies, encephalitis, staining for viral antigen

–PCR

–Virus isolation in cell culture or by intracerebral injection into mice

Question 7

How can we control rabies?

Answer 7

• Quarantine
• Control programs

–(neutering) of stray dogs

–Vaccination of dogs and cats

• Pet Travel Scheme (PETS)
• Control of rabies in wildlife reservoirs

Question 8

What kind of virus causes West Nile Virus?

Answer 8

ssRNA, flavivirus

Question 9

What are the clinical signs of west vile virus in horses?

Answer 9

• Most horses do not develop disease following infected mosquito bite
• But Virus causes severe encephalitis and/or meningitis in ~33% of sick animals

–fatal or requiring euthanasia

•May show ataxia, lethargy, facial paralysis, blindness, seizures, recumbency etc

Question 10

How can we diagnose west nile virus?

Answer 10

• Clinical signs
• Detection of anti-viral antibodies

–IgM capture ELISA detects recent infection with WNV (within 3mo)

•Post mortem examination of brain

Question 11

How can we control west nile virus?

Answer 11

–Vaccination of horses

• Killed virus vaccine *
• Canarypox recombinant vaccine *

–Reduce opportunities for insect vectors to flourish

–Insect repellents

–Stabling to avoid exposure

Question 12

Equine Viral Encephalomyelitis:

A) What virus causes it?

B) How is it borne?

Answer 12

A) Alphavirus

B) Mosquito borne

Question 13

What are the clinical signs of Equine Viral Encephalomyelitis?

Answer 13

• Similar for all three viruses
• Fever/depression
• Fatal febrile enchephalomyelitis
• Photophobia, head pressing, blindness, dysphagia, ataxia

Question 14

Aujesky’s disease:

A) What causes it?

B) What signs are seen in piglets?

Answer 14

A) Alpha - herpesvirus

B) Repro failures
Neuro disease

Question 15

What is the epidemiology of Aujesky’s disease?

Answer 15

•Endemic in many countries

–Asia, South and central America, Africa

• Canada, USA, UK, Denmark etc disease free but risk of reintroduction
• Spread via oronasal secretions, milk, semen, transplacental
• Pig movement (subclinical/latent)
• Windborne spread over short distances (several km)
• Secondary infections of sheep/cattle by aerosols, dogs/cats by ingestion of meat

Question 16

What is seen in an Aujesky’s disease outbreak?

Neonates

Suckling

Weaners

Answer 16

• Abortion of pregnant sows
• Neonatal pigs

– listless, tremors, incoordination, hypersalivation, convulsions, death in 1-2days.

•Suckling pigs

–circling, paddling of legs, V+/D+

–high mortality rate

•Weaners

–Respiratory signs, fever, death rate <10%

Question 17

What are the key features of Aujesky’s disease in:

A) Cats?

B) Dogs?

C) Cattle?

Answer 17

A) Cats: usually show sudden death

B) Dogs: jaw, pharyngeal paralysis, salivation, scratching, death

C) Cattle: “mad itch”, biting, licking, rubbing often unilaterally; staggering, aggression, circling, death in 3-4 days

Question 18

How can we control Aujeskys disease?

Answer 18

•UK is free of disease

– Slaughter/depopulation

•Endemic areas

–Vaccination: attenuated marker vaccine

Question 19

Classic swine fever:

A) Which virus?

B) How is it spread?

Answer 19

A) Pestivirus

B) Spread by movement of pigs, mechanically or in infected pig products

Question 20

What the clinical signs of Aujeskys disease?

Answer 20

• Erythema, petechiae
• Fever (>40C)
• Depression, anorexia
• Piglets can show convulsions and tremors
• Constipation/Diarrhoea
• Abortions, stillbirths
• Haemorrhagic lesions on multiple organs

Question 21

What are the differentials for aujeskys?

Answer 21

•Porcine dermatopathy and nephropathy, African SF

Question 22

Teschen Disease:

A) What is it?

B) What are the signs?

Answer 22

A) Porcine enteroviral encephalomyelitis

B) Fever, depression followed by incoordination, paraplegia, paralysis

Question 23

What are the clinical signs of BSE?

Answer 23

• Highly variable
• Nervous, hyperexciteable, aggressive
• Weight loss
• Drop in milk yield
• Ataxia, hypermetria

Question 24

Name clinical signs of scrapie

Answer 24

• Nervous, excitable, head tremors
• Pruritus
• Scratch reflex (nibbling)
• Weight loss

Question 25

What do vet surgeons or farmers do i they suspect scrapie or BSE?

Answer 25

Report

Question 26

What is the Compulsory Scrapie Flock Scheme (CSFS)?

Answer 26

The EU introduced compulsory controls in infected flocks and herds in October 2003 (Regulation (EC) No.1915/2003).

In flocks or herds that have had a confirmed case of classical or atypical scrapie.

Disease control options in sheep flocks in which classical scrapie is confirmed, include:

(i) flock genotyping followed by selective killing of sheep with susceptible genotypes or exceptionally
(ii) whole flock killing. For goats the only option is whole herd killing.

In all cases, there is a two year period of TSE testing with negative results before a flock or herd is free of movement restrictions

Also: Routine surveillance of fallen stock