Viro Final Flashcards
Causative agent of BVDWhat
Flavi (pesti)
RNA, E
Transmission of BVD (4)
Direct
I:fomites
Transplacental
Veneral
What immune response is triggered by noncpBVD?
humoral response
What immune response is triggered by cpBVD?
CMI
Where does BVD remain in P.I. males?
seminal vesicles & prostate
Outcome of BVD in pregnant cows
< 80 d= reabsorption
80-125 d = immunotolerant animal f
> 125 d = weak calf syndrome, cerebellar hypoplasia
What can happen to in P.I. calves w/ Mucosal Dz. (chronic BVD)?
- 6-18 mo. no CS
- superinfection w/ homologous BVD or mutation of noncp–> cp
- develop Acute MD
- develop Chronic MD
What is the GS for DX of BVD?
VI & cell culture followed by IF
Causative agent of Infectious Bovine Rhinotracheitis (IBR)?
BHV-1
DNA, E
Transmission of IBR
Direct or transplacental
Site of latency for IBR?
trigeminal ganglia
What drugs can reactivate IBR?
glucocorticoids
What can be seen on necropsy of aborted IBR fetuses?
microscopic necrotic foci only
3 big CS of IBR
hyperemic nasal mucosa –> pustular necrotic lesions
fetid breath
abortion late gestation (rare)
Does the attenuated IBR vax prevent dz?
NO!!
Causative agent of Caprine Arthritis Encephalitis (CAE)
Retro
RNA, E, dip
Transmission of CAE
colostrum or milk
Where are the lesions located at necropsy in CAE?
white matter of CNS
What can be seen in kids 2-4 mo. infected with CAE?
encephalomylitis
How will a goat infected w/ CAE present?
afebrile, alert, good appeptite & sight
lameness, wasting, trembling, dull hair coat
How do you protect kids from CAE?
no vax
separate kids from doe @ birth give heated colostrum/milk or cow colostrum (reduces by 90%)
Causative agent of scrapie?
PRIONS!!!
Where are lesions seen @ necropsy in Scrapie?
grey matter of CNS
NO Inflammation/immune response
Onset of Scrapie?
insidious (2-5 yrs)
DX Scrapie?
IHC w/ anti-PrP(sc) monoclonal Abs
Can goats get Scrapie?
yes!!
Causative agent of EIA
Retro
RNA, E
Transmission of EIA
M: horse fly & stable fly
V: placenta & milk
Iatrogenic
When does EIA transmission peak?
summer & fall
3 main pathogenesis of EIA
anemia
immunopathy (vasculitis, glomerularnephritis)
thrombocytopenia
C.S of ACUTE EIA
severe anemia, jaundice, bloody feces, tachypnea & petechia (80% fatal)
What happens in SUBACUTE EIA?
mod fever
recovery = w/ appearance of neutralizing Abs
What happens in RECOVERED EIA patients?
perform well
may can get dz. again when stressed
CS of CHRONIC EIA
failure to thrive
fever, cachexia, anemia & ventral edema
DX of EIA?
Coggin’s Test - survey
PCR - confirm
Causative agent of EVA
Arteri
RNA, E
Transmission of EVA.
I: aborted fetal fluids
V: placenta
Veneral
What is the incidence of abortion in EVA?
Sporadic –> 50% in naive mares –> btwn 5-10 mo. of gestation
C.S. of EVA in foals & yearlings?
Severe RT dz
Death - pneumonia & intestinal necrosis
C.S. of EVA in adults
- conjunctivitis
- ocular discharge
- Edema- palpebral, limbs, ventral abdomen, scrotum & prepuce
- diarrhea
- photophobia
GS DX of EVA
RT-PCR
from nasalpharyngeal swabs, blood, urine or aborted fetal tissue
What is the morbidity & mortality of EVA.
high morbidity
low mortality
DDX of EVA
EIA
Equine herpesvirus
Equine Influenza
What is different about Arteriviridiae?
like cold
E but STABLE in environment
Causative agent of Equine Encephalitides
Toga
RNA, E
Transmission of EEE, WEE, & VEE
M- mosquitoes
birds = reservoir & amplify
What is crucial for transmission & CNS invasion of EEE?
2nd viremia
DX of EEE, WEE, & VEE?
IgM ELISA
RT-PCR from brain tissue post mortem
DDX of Equine Encephalitides?
Rabies, EHV-1 & WNV
Causative agent of WNV?
Flavi
RNA-E
Transmission of WNV?
ARBOVIRUS!!!! (mosquitoes)
Is WNV zoonotic? What’s the reservoir?
YES!!
birds
Causative agent of Equine Rhinopneumonitis.
EHV-4
Pathogenesis of Equine Rhinopneumonitis (EHV-4) in young horses?
Acute RT dz w/ mild-subclinical infections
Pathogenesis of Equine Rhinopneumonitis (EHV-4) in adult horses?
Latent carriers have febrile RT dz after stress
2 big CS of Equine Rhinopneumonitis?
profuse serous nasal discharge –> mucopurulent (rapid)
2ry bronchopneumonia
What virus can agglutinate RBCs in horses?
Adenovirus Pneumonia
Causative agent of Adenovirus Pneumonia?
Adeno
DNA, N
When is Adenovirus Pneumonia a problem in horses?
Arab SCID foals
If get colostrum = shows up 3-6 mo. later (mAbs)
no colostrum = death soon!
What C.S. will you see in Non SCID foals infected w/ adenovirus pneumonia that did not get enough colostrum?
mild RT disease
Causative agent of Equine Influenza?
Orthomyxo = Flu A
RNA, E, Seg
Where does Equine Influenza replicate?
epithelial cells of URT & LRT
2ry infections common with Equine Influenza?
conjuctivitis
bronchopneumonia
chronic pulmonary dz.
guttural pouch infections
C.S. of Equine Influenza?
Extremely high fever –> can aborts
Serous nasal discharge –> mucopurulent (longer than EHV-4)
Depression/anorexia for a few d.; recover in 2-3 wk
DX of Equine Influenza?
VI using serous nasal mucus (must get early!)
How will the herd look w/ Equine Influenza?
many animals sick @ same time
DDX of Equine Influenza?
EHV-1 & -4
Equine Adenovirus Pneumonia
Rhinovirus
(only if in beginning & few animals are sick!)
Causative agent of Equine Abortion?
EHV-1
DNA, E
Where does Equine Abortion (EHV-1) replicate?
in the URT –> get viremia
What can cause CNS signs in Equine Abortion?
vasculitis of CNS –> ischemia & hemorrhagic infarcts
Which form of Equine Abortion causes Resp. dz. w/ HIGH mortality?
Pulmonary vasculotrophic EHV-1
What are some distinguishing C.S. of Equine Abortion?
Urinary incontinence
abortion in last 4 mo. of gestation w/ no CS
(most common cause of late term abortions in equines)
What other Herpes does Equine Abortion resemble?
EHV-4 = equine rhinopneumonitis
What are latent EHV-1 infected horses resistant to? What are they not resistant to?
resistant to Resp dz.
Can still abort
Causative agent of Equine Coital Exanthema (ECE)?
EHV-3
DNA, E
Pathogenesis of ECE?
Stays local–> NO VIREMIA = NO SYSTEMIC SIGNS
What happens to stallions infected with ECE?
decreases libido
fertility is A OKAY
What is the most sensitive DX for ECE?
PCR w/ specific primers
How long should you rest horses w/ flair ups of ECE?
10-14 d (no breeding at this time!)
How can I determine if a horse is an ECE carrier?
Pigment loss on dark skin of genital region
Causative agent of Vesicular Stomatitis?
Rhabdo
RNA, E
Transmission of Ves. Stom,?
I: fomites, food, halters
M: arthropod
enters through skin abrasions
Pathogenesis of Ves Stom?
local only –> no viremia, no systemic dz
What are some CS of Ves Stom?
profuse salivation
vesicles on oral epi & cornary band
DX of Ves Stom?
Authorized labs only
VI, cell culture, serology
Why is Ves Stom a notifiable dz. in cattle & swine?
b/c DDX of FMD
How good is the immune response to Ves Stom?
not great–> short lived Abs–> reinfection happens
Causative agent of CSF?
Flavi (pesti)
RNA, E
What happens to babies born to dams infected w/ Pestivirus? (Flaviviridiae)
P.I infected animals
Immunotolerant
Life-long shedding
Pathognomonic lesion @ necropsy of CSF?
infarction of spleen
Will peracutely infected CSF animals show lesions at necropsy?
no
Pathogenesis of subacute or chronic CSF?
necrotic ulcerations of mucosa in LG intestine
2ry bacT pneumonia & enteritis
GENERAL EXHAUSTION OF LYMPHIOD SYSTEM!!!
2ry C.S of CSF
Paresis, paralysis, convulsion, circling
hyperemia & purpura of ventral abdomen & ears
severe leukopenia
What animals may die from CSF w/o C.S?
young animals
C.S. of pregnant sows w/ CSF
SMEDI
if born alive–> runting, progressive dz., death (wks to mos)
What strains of CSF cause extended or intermittent clinical dz?
moderately virulent strains
DX of CSF?
NOTIFIABLE
Must confirm w/ IF or Ag ELISA
monoclonal Abs will distinguish from BVD
When would you vax for CSF?
endemic areas only
Causative agent of ASF?
Asfa
DNA, E, IN & paracrystaline arrays
What is special about the transmission of ASF? (3)
- M: soft ticks (reservoirs too)
- warthogs are reservoirs –> can’t get rid sylvatic cycle
- US & Caribbean have this tick –> could potentially harbor dz.
Pathogenesis of Acute, Fatal ASF
Gross lesions in lymphatics & vascular system
enlarged friable spleen
petechia in kidney cortex
Pathogenesis of Chronic ASF?
Cutaneous ulcers
Arthritis
Pericarditis
Recovered animals become P.I.
Initial C.S of ASF?
Severe leukopenia
prostration & death
Less common C.S of ASF?
Reddening or cyanosis of ears & snot
hemorrhages from nose & anus
may abort
DX of ASF?
IF or Ag ELISA
NO SEROLOGY
Problems w/ ASF vax?
virus specific Abs provide no protection
virus interferes w/ immune system
doesn’t grow will in cell culture
DDX of ASF?
CSF
Causative agent of Pseudorabies (Aujesky’s Dz)?
herpes
DNA, E, RARE IN inclusion bodies
Transmission of Pseudorabies?
D: saliva & nasal discharge ONLY
I: bad feed, carcasses & rats
wild pigs in South act as reservoirs
Pathogenesis of Pseudorabies?
NO VIREMIA enters via oral/nose No gross lesions in CNS Minute white, necrotic foci in liver & spleen Latency = trigeminal ganglia
C.S of Pseudorabies in endemic areas?
reactivation w/o C.S
C.S of Pseudorabies in pregnant sows?
50% abortion in naive herds
< 30 d: reabsorbs
> 30: abortion, weak or normal piglets
C.S of Pseudorabies in piglets?
100% mortality in ones born to naive sows
mAbs will protect & piglets will recover
C.S of Pseudorabies in cattle?
“Mad itch”, frenzied (CNS) & die rapidly
C.S. of Pseudorabies in dogs?
acting crazy & itchy but DO NOT ATTACK
C.S of Pseudorabies in cats?
DEATH no CS
C.S of Pseudorabies in weaned to adult pigs?
4-8 d course
1st - mild dz
5th d- CNS signs & salivation
6-8 d= moribound & die w/in 12 hours
What happens in adult pigs that recover from Pseudorabies?
go to the meat market–> they suck at growth
GS for DX of Pseudorabies?
Ab ELISA
What is the best method to prevent Pseudorabies infections?
“Farrow to finish” herds & vax in endemic areas
sorry pet piggies - no vax!
What is the most economically important dz. of swine in the US?
pseudorabies
What swine dz are humans refractory for?
Pseudorabies
What is the causative agent of PMWS?
Circo (2)
DNA Naked
How is PMWS transmitted?
Feces to RT
Pathogenesis of PMWS?
Virema
mABs protect up to 6-9wks
What are the 3 forms of PMWS?
Repro failure
Resp. Dz. in finishing pigs
Porcine dermatitis & nephropathy syndrome
What Dx can you not do in PMWS?
Serology
What is the causative agent of swine influenza?
Orthomyxo A, H1N1
RNA E Seg (2 variants)
Pathogenesis of swine influenza?
Sharply demarcated lung lesions w/ hyperemia, consolidation and exudate in airways
2 important CS of swine influenza?
Bronchial rales at auscultation
case fatality rate under 1%
Dx of Swine Influenza?
Need Lab to confirm
VI & IF for subtype
What are the 2 zoonotic Dz of swine?
Swine Influenza & Swine vesicular Dz (O)
Causative agent of PRRS?
Arteri
RNA E
Transmission of PRRS
D, I and AI-semen
more frequent in winter months
Pathogenesis of PRRS
Viremia even w/ ABs
CS of PRRS
Resp & SMEDI Blue ears, snout & vulva agalactia late abortion (day 110) Old swine-->asymptomatic
Dx of PRRS
VI in moribound live piglets
hard to grow in cell culture
Causative agent of swine vesicular Dz
Picorna
RNA N
Transmission of Swine vesicular Dz
abrasions or ingested
shed in feces
Pathogenesis of swine vesicular Dz
viremia
No persistant infection
recovered pigs are immune to reinfection
CS of Swine vesicular Dz
Lots of lame pigs at once–>vesicles on feet
10% vesicles in/on mouth
encephalomyeloitis is rare
Dx of Swine vesicular Dz
Notifiable & Controled- DDX FMD
Must differentiate from other Vesicular Dz’s via Ag ELISA or RT-PCR
How is swine vesicular Dz easily transmitted?
Infected Meat
Causative Agent of Transmissble Gasteroenteritis (TGE)
Corona
RNA, E
Transmission of TGE
fecal/Oral
What emerging Dz in the US is in the same family as TGE?
Porcine Endemic Diarrhea
Pathogenesis of TGE
Only affects villi (shortening)
mIgA is best for protection
CS of TGE
Vomitting and profuse yellow diarrhea–>death w/in 1wk
Few deaths in piglets >3wks
Control of TGE
giving virulent strains to prego sows
good sanitaiton
Mortality of naive neonatal pigs with TGE?
100%
What is the strange Dz pattern in swine of corona virus
Resp. dz
Causative agent of Porcine Parvovirus?
Parvo
DNA, N
Transmission of Porcine Parvo?
everything
persistent infection w/ chronic shedding
boars shed virus in semen (AI prob)
Where does Porcine Parvo replicate?
nucleus of dividing cells (everywhere in young)
What determines the C.S> of Porcine Parvo?
Gestational stage of sow
C.S. of Porcine Parvo?
< 30 d = resorption
30-70 d = SMEDI
> 70 d= live piglets w/ lesions, will recover
What are the reproductive effects of Porcine Parvo?
- increased # of gilts/sows returning to estrus 3-8 wks after breeding
- “Endocrinologically pregnant” animals
- Crappy litters!
- Low fertility in boars
DX of Porcine Parvo?
IF of fetal tissue
NO SEROLOGY
Problem w/ vaccinating for Porcine Parvo?
small window to immunize gilts before breeding them at 7 mo.
mAbs last 6 mo or longer & can interfere w/ vax
Is abortion common in Porcine Parvo?
NO –> SMEDI is!
Causative agent of Marek’s Dz?
Herpes
DNA, E
Transmission of Marek’s Dz
Inhalation of dander ONLY
What is the viremia of Marek’s Dz?
Macrophage associated
Pathogenesis of Marek’s Dz?
Immunosuppression by d. 6 –> affects all lymph organs
T-cells are affected by viral oncogene @ wk 2.
Lesions are from infiltration & proliferation of rogue T-cells
Necropsy findings in birds w/ Marek’s Dz.
Unilateral enlargement of peripheral nerve trunk
Lymphomatous lesions like Avian Leukosis
What are the 4 overlapping syndromes of Marek’s Dz?
Classical = Neurolymphomatosis
Acute
Ocular Lymphomatosis
Cutaneous
C.S. of Classical Marek’s Dz?
Splits & asymetrical paralysis
wing dropping
lowered head
C.S. of Acute Marek’s Dz?
most= depression few= ataxia, paralysis & significant mortality
C.S. of Ocular Lymphomatosis?
gray iris
irregular pupil
partial or total blindness
C.S. of Cutaneous Marek’s?
round nodular lesions < 1cm @ feather follicle
see when plucked
DX of Marek’s Dz?
need pathological & etiological dx!!
Key C.S.
VI w/ buffy coat
Control of Marek’s Dz?
Vax in ovo
Genetic resistance in some birds
9 Key C.S of Marek’s Dz.
- all birds even those < 16 wks
- leg & wing paralysis
- occurs > 5% in unvaccinated flocks
- nerve enlargement
- INTERfollicular tumor in bursa
- CNS involvement
- lymphoid prolif in skin & follicles
- pleomorphic lymphoid cells
- T-cell lymphomas
Causative agent of Chicken Anemia Virus
Circo
DNA, N
Transmission of CAV?
D & I
vertical only during viremia
Pathogenesis of CAV in 3 wk old chicks born to asymptomatic hens?
pale BM aplasia Atrophy of thymus, bursa & spleen SQ intramuscular hemorrhages mortality = 10-50%
DX of CAV
CS- pale, low PCV, watery slow clotting blood
Control of CAV?
Live vax layers
Causative agent of Newcastle Dz?
Paramyxo
RNA, E
Special things about Newcastle?
Zoonotic (o)
Notifiable
velogenic strains exotic to US
BEWARE of caged birds!!
Transmission of ND?
Waterfowl are reservoirs - no dz.
D, I
ONLY lentogenic are vertical (trans ovarain)
What are the virulence of the different strains of ND?
Lento- low
Meso-mod
Velo- HIGH
Pathogenesis of ND
- viremia
- trophism depends on host enzymes for HA & NA
- mAbs protect chicks for 4 wks –> IgY (viremia) & IgA (RT & GIT)
C.S of ND
RT, GIT, CVS, & CNS
not always present together
varies depending on age, immune status, virulence & viral trophism
DX of ND
State labs confirm –> VI followed by HA, HI & IF of trachea samples
Serology ONLY in unvax flocks
Control of ND
Vax of lentogenic strains in water
vax layers every 4 mo.
Causative agent of Infectious Bursal Dz (IBD)?
Birna
RNA, N, bi seg
Transmission of IBD
fecal/oral
fomites
Pathogenesis of IBD in chicks < 3 wks?
subclinical b/c bursa not developed & mAbs
Pathogenesis of IBD in chicks 3-6 wks?
most affected –> CLINICAL DZ
bursa is most active
Virus attacks all IgM B-cells
What are the main issues of IBD infected chickens?
ineffective other vax
immunosuppression
kidney failure
enlarged kidneys–> urates
C.S of Acute IBD in birds?
prostration
dehydration
due to necrotizing effects
C.S. of Subclinical IBD chicks (< 3wks)?
Immunosuppression
Bursal atrophy w/ fibrotic or cystic follicles–> lympocytopenia
birds < 6 wks get 2ry infections & die
Pathogenesis of IBD in chicks > 8 wks?
NONE
Necropsy of Bursa in birds w/ IBD
- Acute - enlarged, edematous bursa
- 5 d- hemorrhagic, normal size bursa
- 8 d post infection- atrophy up to 1/8 size of bursa, now immunosuppressed
DX of IBD
mostly HX, CS & necropsy
serology only unvax flocks or vax response
Control of IBD
Layers: get live oral vax @ 18 wks
sickly chicks: attenuated vax @ 1-2 wks
Constant vax adaptation necessary
What is the morbidity & mortality of IBD?
100% morbidity
Mortality: 20-90% varies
Causative agent of Avian Leukosis?
Retro
RNA, E
Transmission of AL?
D: saliva & feces ONLY w/ long, close contact
Vertical: Congenital
infected meconium @ hatching
What happens in congenitally AL infected chicks?
get whole virus chronic viremia immunotolerant chicks persistent shedders leukemia common
What happens in genetically transmitted AL?
chicks only get pro-virus (sperm can’t support)
latent chicks
No viremia
No leukemia
3 different pathogenesis of avian leukosis?
- replication comp= lymphoid leukosis, osteopetrosis, renal tumors
- replication defective = decreased erythrocytes, myeloblasts, myelocytes; tumors
- Rous sarcoma
C.S. of Avian Leukosis
No CNS –> differentiates from Marek’s
Immunosuppression
GI signs
Lesions: liver, kidney, spleen & bursa
DX of Avian Leukosis?
HX/CS
serology
Control of Avian Leukosis?
breed for genetically resistant flocks
DDX of Avian Leukosis?
Marek’s Dz
What age group of birds is Avian leukosis sporadic in?
> 14 wks
Causative agent of Avian Influenza?
Orthomyxo A
RNA, E, Seg
Transmission of Avian Influenza?
Direct contact
POO- high conc.
Waterfowl major reservoir
Pathogenesis of Avian Influenza?
Viral HA determines virulence (host enzymes play a role)
Viremia
What is the most virulent form of Avian Influenza?
FOWL PLAGUE–> sudden death
C.S in older birds w/ Avian Influenza?
Cessation of egg laying
edema of face & neck
cyanosis of comb & wattle
DX of Avian Influenza?
Requires lab–> isolate & determine virulence
RT-PCR
Serology retrospective
ZOONOTIC
What is cool about Avian Influenza?
survives long time in H2O & @ low temp
Causative agent of Avian Infectious Bronchitis (AIB)?
Corona
RNA, E
Transmission of AIB?
D: poo on food
I: fomites in cold
P.I chicks
Pathogenesis of AIB?
yellow casts block bronchi in young chicks –> death
ova can rupture–> free yolk in abdomen of layers
Induces IgM, IgY & IgA
C.S. of 1-4 wk old chicks w/ AIB?
cough, rales, snot, dyspnea,
only lasts 5-7 d –> recover
C.S of AIB in broilers?
high mortality due to 2ry infections
C.S. of AIB in layers?
stops laying eggs
FUNKY EGGS!!! once resumes
pasting–> EWWWWWWW
DX of AIB?
direct IF tracheal smears early
RT-PCR
serology types
Control of AIB
vax doesn’t prevent dz
vax breaks are common
Causative agent of Avian Reovirus?
Reo
RNA, N, seg
Transmission of Avian Reo?
fecal oral
Morbidity & mortality of Avian Reo?
High morbidity
low mortality
C.S. of Avain Reo?
inappearent to fatal
- Arthritis
- myocarditis
- hepatitis
- Chronic resp
- malabsorption–> looks like shit
DX of Avian Reo?
IF
VN
Control of Avian Reo?
Stay clean Yo
test & quarantine new birds
Causative agent of Fowlpox?
Pox
DNA, E
DDX of Diptheric Fowlpox
Vit A deficiency
other respiratory dzs.