Notifiable Neuro Viruses Flashcards
Name 5 notifiable viruses (7)
- Rabies
- West Nile Virus
- Equine Viral encephalomyelitis
- Aujesky’s
- Teschen Disease
- Classical Swine Fever
- (BSE/scrapie)
What does the image show?
Rabies
Wha is the genus of rabies?
Lyssavirus
Where are the following animal found with genotype 1 classic rabies:
A) Fox?
B) Dog?
C) Bat?
D) Raccoon?
E) Skunk?
A) West Europe
B) Misse eat, Africa, East Europe
C) North and South Amercia
D) North America
E) North America
What are the altered bahviours associated with rabies?
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
How can we diagnose rabies?
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
How can we control rabies?
- Quarantine
- Control programs
–(neutering) of stray dogs
–Vaccination of dogs and cats
- Pet Travel Scheme (PETS)
- Control of rabies in wildlife reservoirs
What kind of virus causes West Nile Virus?
ssRNA, flavivirus
What are the clinical signs of west vile virus in horses?
- 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
How can we diagnose west nile virus?
- Clinical signs
- Detection of anti-viral antibodies
–IgM capture ELISA detects recent infection with WNV (within 3mo)
•Post mortem examination of brain
How can we control west nile virus?
–Vaccination of horses
- Killed virus vaccine *
- Canarypox recombinant vaccine *
–Reduce opportunities for insect vectors to flourish
–Insect repellents
–Stabling to avoid exposure
Equine Viral Encephalomyelitis:
A) What virus causes it?
B) How is it borne?
A) Alphavirus
B) Mosquito borne
What are the clinical signs of Equine Viral Encephalomyelitis?
- Similar for all three viruses
- Fever/depression
- Fatal febrile enchephalomyelitis
- Photophobia, head pressing, blindness, dysphagia, ataxia
Aujesky’s disease:
A) What causes it?
B) What signs are seen in piglets?
A) Alpha - herpesvirus
B) Repro failures
Neuro disease
What is the epidemiology of Aujesky’s disease?
•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
What is seen in an Aujesky’s disease outbreak?
Neonates
Suckling
Weaners
- 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%
What are the key features of Aujesky’s disease in:
A) Cats?
B) Dogs?
C) Cattle?
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
How can we control Aujeskys disease?
•UK is free of disease
– Slaughter/depopulation
•Endemic areas
–Vaccination: attenuated marker vaccine
Classic swine fever:
A) Which virus?
B) How is it spread?
A) Pestivirus
B) Spread by movement of pigs, mechanically or in infected pig products
What the clinical signs of Aujeskys disease?
- Erythema, petechiae
- Fever (>40C)
- Depression, anorexia
- Piglets can show convulsions and tremors
- Constipation/Diarrhoea
- Abortions, stillbirths
- Haemorrhagic lesions on multiple organs
What are the differentials for aujeskys?
•Porcine dermatopathy and nephropathy, African SF
Teschen Disease:
A) What is it?
B) What are the signs?
A) Porcine enteroviral encephalomyelitis
B) Fever, depression followed by incoordination, paraplegia, paralysis
What are the clinical signs of BSE?
- Highly variable
- Nervous, hyperexciteable, aggressive
- Weight loss
- Drop in milk yield
- Ataxia, hypermetria
Name clinical signs of scrapie
- Nervous, excitable, head tremors
- Pruritus
- Scratch reflex (nibbling)
- Weight loss
What do vet surgeons or farmers do i they suspect scrapie or BSE?
Report
What is the Compulsory Scrapie Flock Scheme (CSFS)?
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
