Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/154

Click to flip

154 Cards in this Set

  • Front
  • Back
Describe the genome of Rhabdoviridae
Enveloped, bullet-shaped RNA
What are the main rhabdoviridae viruses?
Rabies
Vesicular stomatitis
Bovine Ephemeral fever
Describe the pathogenesis of rabies
Myocyte infection->uptake at nerve endings -> brain-> salivary glands
What is the incubation, shedding and clinical course of rabies?
Incubation- 2weeks-2years
Shedding- 1-7 days prior to clinical signs
Course- <10 days
How long would we quarantine an unvaccinated animal bitten by a wild animal?
6 months
Quarantine for an animal that bits a human?
10 days
When is rabies highly susceptible to antibody?
During incubation, prior to entry into nerve endings
Two forms of rabies?
Furious- behavior changes

Paralytic- paralysis
Where does the rabies virus replicate?
Hippocampus, brain stem, cerebellum, spinal cord
What is observed in the furious form?
Changes in behavior, aggression, loss of fear*
Describe the symptoms of the paralytic rabies
paralysis of facial muscles, dysphagia, limb paralysis
How is rabies transmitted?
Animal reservoirs: saliva deposited in wound
Aerosols
Tissue transplants
Name two ways the rabies vaccine is effective
Prevents disease and shedding
Can block the pet-people chain
How is rabies diagnosed?
Histopathology: intracytoplasmic inclusion bodies in CNS
Immunofluorescence: rabies proteins in CNS (method of choice)
How is vesicular stomatitis virus different than FMDV?
It causes disease in horses where FMDV does not!
Clinical signs of Vesicular stomatitis virus?
fever, anorexia, profuse salivation, lameness
What is bovine ephemeral fever virus?
3 day stiff sickness
not in the us, trade restrictions
What type of viruses are retroviruses?
RNA with a reverse transcriptase and an integrase
What are the three mechanisms of retrovirus oncogenesis?
1) Insertional mutagenesis (slow, leukemias)
2) Transduction of c-onc genes (fast, sarcomas)
3) Trans-activation: humans
Why is insertional mutagenesis slow?
It involves the virus to insert near an onco gene, which are few and far between (minefield example)
How does transduction of c-onc genes work?
Sarcoma viruses, which are replication defective, recombinate to include the onco gene
What viruses use trans-activation of cellular onco genes/
BLV and HTLV only, uses Tax gene
Are leukemia viruses replication competent?
Yes
Are sarcoma viruses replication competent?
No
How long is the latent period of leukemia viruses?
4-6 months
Which avian leukemia/sarcoma viruses are replication competent?
Lymphoid leukosis
Osteopetrosis
What disease is lymphoid leukosis similar to?
Mareks disease, neoplastic disease
How are avian leukemia/sarcoma viruses transmitted?
Through the egg!
How are avian leukemia/ sarcoma viruses controlled?
Maternal antibody protects from 4-7 wks, no vaccine
How does lymphoid leukosis differ from marek's disease?
Lymphoid leukosis: later paralysis (>16 wks), nodular tumor in bursa

Marek's: <4 wks, large tumor, PNs
Describe FeLV
Feline Leukemia/Sarcoma Virus is an oncogenic retrovirus with 3 subgroups A,B and C.
Most important infectious disease of cats
What are the 3 outcomes of FeLV infection?
1) effective immune: cleared, resistant
2) Latent carriers: don't shed, susceptible to clinical disease
3) Persistently viremic: shed virus, die within 3 years
How is FeLV tested for?
part of SNAP test
ELISA for Ag
What is unique about FeLV antibodies?
3 details
1- neutralizing antibodies against gp71, type specific
2- antibodies group specific
3- FOCMA antibodies: protective against neoplastic disease only, not a viral antigen
How is FeLV transmitted?
Saliva from infected cats
How is bovine leukemia virus (BLV) classified?
Enzootic: adult cattle (65% asymptomatic carriers, 30% persistent lymphocytosis)
Sporadic: 3 types, BLV not the major cause
What is persistent lymphocytosis?
Benign lymphoproliferative condition, above normal white cell count
What are the symptoms of BLV?
Eye tumors, heart tumors, enlarged lymph nodes
How is BLV related to other disease?
90% of adult cattle with lymphosarcoma have BLV
What is the prevalence of BLV?
Dairy cattle: 20% infected
Beef cattle: 2% infected
What are lentiviruses?
Non-oncogenic retroviruses, primarily horizontally transmitted, cause persistent infections and gradual onset of progressive disease
What do lentiviruses have a tropism for?
Either macrophages or T-helper cells
What is Visna-Maedi virus?
Maedi- OPP in the US, respiratory form, death from secondary infection

Visna- meningoencephalic form
What is Caprine Arthritis-Encephalitis?
widespread lentivirus, 80% of US goats have antibodies but 25% of these get clinical signs
What is EIAV?
Equine infectious anemia virus (lentivirus, type of retrovirus) also called swamp fever
What are the types of EIAV?
Acute: sudden onset of fever, anorexia, thirst, petechial hemorrhages, death can
Subacute: lack of clinical signs, can transmit
Chronic: febrile episode, anemia (complement mediated destruction)
What type of EIAV does an anemic infected horse have?
Chronic
How is EIAV transmitted?
biting insects
How do we test for EIAV?
Immunodiffusion test: Coggins
ELISA for antibody
What is FIV?
Feline immunodeficiency virus
Non-oncogenic (lentivirus) retrovirus
In the cat population at 1.5-3%
12% incidence in cats with FeLV
What are the clinical signs associated with FIV?
wide variety: fever, anemia, neurologic, abortion, diarrhea
Has immunosuppressive properties so these could be secondary
How is FIV transmitted?
Like all lentiviruses, primarily horizontal
Males> Females due to fighting, saliva exposure in bites
How do we test for FIV?
ELISA for antibodies (antibodies=infection)
What is the significance of BIV?
In 5-10% of cattle, no idea what it might be doing
What is the difference in ELISA for FIV vs FeLV?
FIV: tests for antibodies
FeLV: tests for antigen
EIAV: coggins test for antibody
What are the characteristics of the Parvo family?
ssDNA, non-enveloped, acid resistant
Lytic infections of rapidly dividing cell populations, fetus/neonate especially susceptible
What do parvoviruses need?
Cell in the "S" phase of the cell cycle (DNA synthesis phase)
What is Feline Panleukopenia virus?
All felines susceptible
Fecal-Oral transmission
Depletion of leukocytes
How does FPLV kill kittens?
Dehydration!
How is FPLV transmitted?
Fecal->Oral
Virus is very stable in the environment
Describe the FPLV vaccine
Inactivated vaccines used for pregnant cats
Don't use modified live vaccines for pregnant cats
Describe Canin Parvovirus 2
CPV-2 is closely related to Feline Panleukopenia virus FPLV (no cerebellar hypoplasia as in FPLV but myocarditis instead)
What are the signs of CPV-2
Severe hemorrhagic diarrhea with leukopenia
High mortality in early years
What is the pathogenesis of CPV-2?
Hemorrhagic enteritis- crypt cell destruction
Mycardial Infection- cardiac myofibrils destroyed
How is CPV-2 transmitted?
Fecal->Oral
Very stable in the environment
How is CPV-2 controlled?
MLV and killed vaccines
Can also use FPLV vaccines
When is Porcine Parvovirus a concern?
In utero infections!
First half of gestation- cause SMEDI
How can parvoviruses be identified histologically?
Intranuclear inclusion bodies
Describe Papillomaviruses
Direct contact transmission
Self limiting
Spontaneously regress
Highly contagious, epizootic in kennels
What is the pathogenesis of papillomaviruses?
They attack the basal layer of dividing epidermal cells: stratum germinatum
Describe the Circoviridae virus
one molecule of circular ssDNA
very environmentally stable
What is CAA?
Chicken anemia agent (type of circovirus)
Transmitted in ovo! and horizontally
How does CAA cause infection?
Chicken anemia agent rarely causes infection by itself, but with Marek's or infectious bursal can cause high mortality
Anemia by itself
What does CAA target?
Chicken Anemia Agent attacks the bone marrow and thymus
Describe Adenoviruses
Nonenveloped, DNA
Intranuclear inclusion bodies
Transmitted in secretions
Describe the difference between CAV-1 and CAV-2
CAV-1 is endothelium
CAV-2 targets epithelium
Antigenically distinct!
Which CAV type causes blue eye?
CAV-1, endothelium and hepatic cells targeted
Describe the spread of CAV-1
Tonsils-> lymph nodes-> thoracic duct-> viremia-> eye, liver, kidney, other
What causes Blue eye?
CAV-1 causes this due to immune complexes deposited in the anterior uvea, and can also be caused by the CAV1 vaccine
When is CAV2 a health concern?
It can open for a secondary bacterial infection to cause Kennel Cough
Which vaccine do we use in canine adenovirus infections?
CAV2 because 1 can cause blue eye and CAV2 MLV can protect against both
What is the importance of Bovine adenovirus?
No vaccine because of 10 serotypes
Infections not very important unless in mixed
Which CAV is Bovine adenovirus like?
CAV-2 because both are respiratory, endothelium targets
When is Equine adenovirus a concern?
When combined with CID (B and T cell deficiency) it can cause severe pneumonia, conjuctivitis and enteritis
What cause egg drop syndrome and what is it?
Avian adenovirus
Decreased egg production and no shells
What does hemorrhagic enteritis of turkeys cause?
Avian adenovirus that causes bloody diarrhead and death due to hemorrhage of intestinal villi, indirectly occurs due to death of endothelial cells
Describe the Pox viruses
Largest viruses, extremely stable outside of host, cytoplasmic inclusion bodies
Macule->papule->vesicle->pustule->ulcer
Describe the importance of Vaccinia Virus
Type of poxvirus, used to be important in curing small pox but now no longer used
What is advantageous about pox viruses?
Lifelong immunity after exposure for the most part
What is contagious pustular dermatitis of sheep (ORF)
Type of pox virus
Lesions on skin/lips make suckling difficult
seen in spring/summer
What is bovine papular stomatitis?
Pox virus
Causes ulcerative stomatitis
Major importance: can be confused with FMDV
What is African swine fever virus?
Pox virus, dsDNA, very stable
ONLY DNA animal virus transmitted by arthropods
Similar clinically to hog cholera
What is unique about african swine fever?
only DNA virus transmitted by arthropods
Describe the immune response of African Swine Fever virus
Nearly 100% mortality
Infection elicits precipitating and complement fixing antibody but not neutralizing antibody
Describe Herpesviridae
Enveloped DNA viruses
Intranuclear inclusion bodies
Three subfamilies: alpha, beta, gamma
Describe Alphaherpes viruses
Rapidly Growing
Highly lytic
Latent in nervous tissue
Describe Betaherpes viruses
Slow growing
Cytomegalic
Latent in kidney
Describe Gammaherpes viruses
Growth/transformation of lymphocytes
Latent in lymphoid tissue
What are the alphaherpes virus tropisms?
Epithelium
Nervous tissue
What kind of disease do alphaherpes viruses cause?
Respiratory, reproductive, CNS and multiorgan neonatal->Fatal
Describe alphaherpes virus pathogenesis
Primary infection always followed by persistent/latent
Lifelong infection, intermittent shedding with or without recrudescence
Describe Bovine Herpesvirus 1
(aka IBR)
Infectious bovine rhinotracheitis virus:
Respiratory disease
Genital infection-> reproductive failure
Why is BHV1 important?
Role in shipping fever: latently infected animal shipped-> stress causes reactivation-> susceptible cattle get shipping fever
How is BHV1 controlled?
Modified live vaccine- intramuscular or intranasal
Annual revaccination
Describe Adenoviruses
Nonenveloped, DNA
Intranuclear inclusion bodies
Transmitted in secretions
Describe the difference between CAV-1 and CAV-2
CAV-1 is endothelium
CAV-2 targets epithelium
Antigenically distinct!
Which CAV type causes blue eye?
CAV-1, endothelium and hepatic cells targeted
Describe the spread of CAV-1
Tonsils-> lymph nodes-> thoracic duct-> viremia-> eye, liver, kidney, other
What causes Blue eye?
CAV-1 causes this due to immune complexes deposited in the anterior uvea, and can also be caused by the CAV1 vaccine
When is CAV2 a health concern?
It can open for a secondary bacterial infection to cause Kennel Cough
Which vaccine do we use in canine adenovirus infections?
CAV2 because 1 can cause blue eye and CAV2 MLV can protect against both
What is the importance of Bovine adenovirus?
No vaccine because of 10 serotypes
Infections not very important unless in mixed
Which CAV is Bovine adenovirus like?
CAV-2 because both are respiratory, endothelium targets
When is Equine adenovirus a concern?
When combined with CID (B and T cell deficiency) it can cause severe pneumonia, conjuctivitis and enteritis
Describe Malignant catarrhal fever virus
Gammaherpes virus
Affects ruminant
Death in accidental hosts
What are the clinical signs of malignant catarrhal fever?
(Gammaherpes)
Fever
Catarrh: nasal/ocular discharge
Death!
Describe Pseudorabie
Aka Mad Itch
Eradicated from commercial swine
Present in feral swine
How is Pseudorabies spread?
Aerosol, bite, ingestion
Describe pseudorabies pathogenesis in accidental hosts
Exposure-> neurologic infection (PRURITIS)-> death
How is pseudorabies effect determined in swine?
Young: multiorgan neonatal infection, high mortality!
Old: mild disease, abortion
How is pseudorabies controlled?
ML vaccine with gene deleted products, allows for testing between vaccinated and wild-type infected
How does pseudorabies have a high cost?
Persistent infection, life long shedding
Economic losses: respiratory disease, low market value
Describe Canine Herpes Virus
Common infection but uncommon cause of disease
Multiorgan neonatal infection in puppies <3 wks
Describe the effect of CHV on a puppy <3wks and Ab-
Multiorgan neonatal infection, high mortality
Anorexia, diarrhea, death!
Describe the pathogenesis of infection of puppies in the narrow window
Requires:
Immune naive dam
CHV exposure of dam during last 3 wks of gestation of 3 wks after parturition
How is Canine Herpes virus unique pathogenically?
Optimal replication at 35C (clinical sign is hypothermia)
How could you treat CHV?
Increase ambient temperature to ~38C (virus ideally at 35C)
How is CHV controlled?
No vaccines
Allow bitches to contact older dogs prior to breeding and then isolate during the susceptible period
Describe FHV
aka Feline rhinotracheitis virus
Primary infection: respiratory, conjunctivits, abortion
Recrudescence: keratitis, respiratory
How is FHV controlled?
Modified live vaccine
How is FHV treated?
Supportive care: fluids, electrolytes, antibiotics
L-Lysine: suppresses FHV replication
What are the types of Equine herpes virus?
EHV1: respiratory, neurologic, abortion
EHV3: genital
EHV4: respiratory
Describe the effects of EHV1
Equine abortion virus
Respiratory disease in foals
Neurologic disease in adults
How does EHV1 cause abortion?
Primary infection: cell-associated viremia in leukocytes, goes to placenta/fetus
What brings on neurologic disease from EHV1
Re-exposure when Ab titer is waning, type III hypersensitivity- vasculitis
What does EHV4 cause?
Respiratory disease in foals
Rarely: bronchopneumonia
How is EHV1/4 controlled?
vaccines
Immunity short lived, vaccinate at 6 month intervals
What is EHV3
Genital infection, similar to BHV1
What is infectious laryngotracheitis?
Herpes virus in chickens
Respiratory disease
Decreased egg production
What are the clinical signs of infectious laryngotracheitis?
Dyspnea
Expectoration of blood
Conjunctivits
Increased mortality (young)
Describe ILT (infectious laryngotracheitis) pathogenesis
Aerosol exposure -> tracheal epithealial infection -> necrosis-> blood in lumen ->death
What is Marek's disease?
Neoplastic disease of chickens, can be confused with lymphoid leukosis
T cell tumors in sexually immature chickens <4 months
What are the clinical signs of Mareks?
Paralysis!
blindness
secondary infections
(Often combined with CAA- chicken anemia agent, circovirus)
How does Mareks cause disease?
Neurolymphomatosis: transformed t cells accumulate in nerves-> paralysis
Nerve Enlargement
How is Mareks controlled?
Herpesvirus of turkeys vaccine
Modified live MDV vaccines
Given in ovo 90%
Why is cercopithecine herpes virus a concern?
B virus of macaques
Zoonotic with high mortality
Life long shedders
What are the properties of transmissable spongiform ecephalopathies?
Infectious agent is highly resistant to physical and chemical inactivation
No immune response by host
Infection isn't immunosuppressive
How do scrapie associate prions differ from normal?
Infectious
Insoluble
Rich in B sheets
Teaches normal prions to misfold
What is Scrapie?
Slowly developing disease, 1-5yr incubation
Affects sheep
What are the clinical signs of scrapie?
Pruritis
No fever
eventually motor problems and paralysis
How did Scrapie occur?
Vaccine accident
How is scrapie transmitted?
direct or indirect contact (infected pasute for up to years)
What is bovine spongiform encephalopathy?
Mad Cow
Spongiform lesions in brain
Originated from scrapies (as was transmissable mink encephalopathy)
What is the relationship between BSE and variant Creutzfeldt-Jacob?
strong connection, unknown specifics