Vax and Diagnostics Smallies and Equine Flashcards
Outline an ideal vaccine
- provides protection against all strains of pathogen
- prevents infection and shedding
- provides rapid and long lived immunity after single dose
- induces immunological memory so minimal boosters required
2 possible vaccine composition
> passive (ab) - colostrum - anti-serum > active (ag +- adjuvant) - modified live - killed - toxoid - subunit - recombinant
Which immunoglobulins are best at stimulateing cell mediated and mucosal protection?
- IGA muosal
- IgG cell mediated
Up to what age may MDA interfere with vax?
12-14w
After 14w of age, how many doses do modified live vax require? Inactivated/subunit?
- mod live 1 dose
- subunit min 2 doses 2-3w apart
> boosters q6mo-3y depdning on manufacturer guidelines
Youngest possible age to vax
6w, never younger than this
6-12w grey area (hemce multiple doses required)
What 3 sources of information on vaccinations will you receive?
- WSAVA guidelines
- VMD datasheets
- vaccine manufacturers assocaiton
> different recommednations!
WSAVA guidelines on vax dogs?
> core - CDV (distemper) - CPV (parvo) - CAV (infectious hepatitis) \+- rabies endemic areas > non-core - Letospirosis - KC (Pi, BB, coronavirus) > 1* course 3 injections @ 8, 12 and 16 weeks - post vax serology - booster @ 1y then no more frequently than 3y (Lepto, Pi, BB need yearly) - serology to see if booster required
WSAVA guidelines on vax cats?
> Core - Calicivirus (catflu) - Herpesvirus (catflu) - Panleukopenia (enteritis) \+- rabies endemic > Non-Core - FeLV - Chlamydia - BB > 1* course 3 injects @ 8, 12 and 14w - post vax serology - booster @ 1yo then no more freq than 3y
What 2 dose regimes are commonly used and why?
- allows earlier socialising
- 1st @ 6-8w
- 2nd @ 9-10w
( should have 3rd @ 16w to ensure full imunity but this may not be on the data sheet)
If booster lapses do you need to restart 1* course?
NO! memory cells still present just need stimulating (Ab may have waned)
Are vax 100% effective if given by the data sheet?
NO
How effective are FIV and FIP vax?
> FIV - Fel-O-vax - 2 strains covered - 70% effective > FIP - actually enteric coronavirus (not FIP) - IgA intransala vax - kittens often exposed before vax so not very effective
How can ‘vaccines’ be used therputically?
- DNA vax (human tyrosinase) for tx canine malignant melanoma
- desensitising immunotherapy
Which website should be checked for current legislation on rabies vax?
www.gov.uk/take-pet-abroad
Is the Leishmania vaccine effective?
> CaniLiesh
- 3 doses 3w apart
- boosted annually
- not v efficacious but will v clinical dz
How effective are the core cat vaccines?
Cat flu vax not very effective - don’t prevent infection just minimise clinical signs and shedding so likely to become a latent carrier
- may experience flare-ups when old/weak/immunocompromised
> panleukopenia good vax, effective
Potential adverse effects of vaccination?
- RARE
- often mild (transient pyrexia and lethargy)
- allergic reactions IgE mediated occasionally occour (eg. facial pruritis and oedema)
- link between adjuvate vax (FeLV and rabies) and feline ISS
> Non-adjuvanted vax (eg. canarypox vector) available to avoid this
What are rabbits vaccinated against?
- myxomatosis
- viral haemorrhagic disease
> can get them in a combined vial now
What can horses be vaccinated against?
> passive - hyperimmune equine plasma for FPT foals - tetanus antitoxin (wounds) - rotavirus vax for pregnanct mare to roduce MDA for foal > active - equine influenza - tetanus toxoid ~ equine herpes virus (EHV1, EHV 4) ~ MNV, EVA, strangles
Current BHS/jockey club and FEI rules on equine vax?
> 1st dose - flu and tet
2nd dose - flu and tet 21-92d later [BHS/jockey club horses can compete 7d after this 2nd dose]
3rd dose - flu 150-215d later
Booster
- BHS/jockey: within 365d previous injection
- FEI: within 365d previous injection and within 6months +21d of FEI competition
Last vax must be administered min 7d before competing
Reasons for vaccine failure
- strinas/serotypes not protective against the infective cause (Feline calicivirus, leptospira serovars, influenza)
- vax not stored properly or expired
- not administered properly
- animal too old/young (6-9w protocol this may be a problem)
- interference MDA
- prior exposure to pathofen (eg. FeLV, herpes)
- genetic problem eg. MHC genes in Rottweilers pdf vax failure
When is serology testing for response to vax seen in companion animals?
> rarely!
- DHP for dogs, CHP for cats poss
- rabies serology under PETS scheme used to be compulsory, not any more (test 3-4w post vax)
some brands better vax than others (Rabisin (merial) > Nobivac (MSD))
Is there a vax for strangles?
Yes
- equilis Strep E
- withdrawn but relaunched
- stimulates cell mediated immunity by injecting into lip
What are the phases of antibody production and how may this affect serology testing?
> lag
- may be ab - even if infected (does not mean pathogen negative!)
- need 2 negative samples consequtively to decide it is negative (acute and convalescent sera 2-3w apart to show rising titres)
log
plateaux
decline
~ antibody isotype analysis also helpful
- IgM first Ab produced, normally wanes in favour of IgG
- if IgM>IgG then infection is acute
Which tests are commonly performed in house or by labs for serology?
- ELISA
- RIM (rapid immune-migration assay)
- IFAT (indirect immunofluorescent ab test)
- VN (virus neutralising) assay
- HA (haemaglutinin inhibition) assay
DOGS Which pathogens are serological tests available for in the dog?
- distemper
- parvovirus
- adenovirus
- herpesvirus
- coronavirus
- parainfluenza
DOGS What pathogens should you conisder in dogs with neurological disease, myositis or PUO?
- toxoplasma gondii (IgM and IgG)
- neospora caninum
> serology
DOGS What pathogens should you consider in dogs with acute kidney disease?
- leptospira MAT serology (microscopic agglutination test)
DOGS Which pathogens can be serologied if fungal rhinitis is suspected?
- aspergillus
- cryptococcus
(as hard to culture serology prefered)
DOGS What skin parasite can be detected serologically?
scabies
CATS which serological tests are available for cats?
- FIV (Ab SNAP test)
- FeLV (Ag SNAP test)
- Toxoplasma/Neospora
- “Cat flu” feline calicivirus, herpesvirus and chlamydophila
- FIP CARE
Why should care be taken when interpretting FIP serology?
- demonstrates exposure to enteric coronavirus NOT NECESSARILY the mutated version pregression to FIP
- Dx should be based on clinical signs and lab findings
- coronavirus titre > 640 would be consistent with the dz if clinical signs also present
Where are many serological tests for horses available?
- AHT
Specific serology test available for horses?
- EHV1 and 4 (abortion, resp and neuro dz)
- EHV 3 (coital exanthema)
- resp dz (influenza, adenovirus, rhinovirus)
When may serological tests be specifically required for equines?
- import/export/breeding and sales
- see DEFRA website for more details on import/export
> Breeding
-EVA and EIA most commonly
> import - Vesicular stomatitis, Dourine, Glanders
