Herpesviridae

Question 1

Bovine

Answer 1

Bovine herpesvirus type 1
- iBR: encephalitic, respiratory, reproductive forms
Bovine herpes virus type 2
- mammillitis
Bovine Herpesvirus type 3
- malignant catarrhal fever (american and african form)

Question 2

Porcine

Answer 2

Pseudorabies virus

• Aujeszky’s disease: swine, respiratory, fetal death, abortions, mummies, high mortality in young
• highly fatal pruritis, paralysis in dogs, cats, ruminants, raccoons, rabbits, birds

Question 3

Pseudorabies virus does not infect _____ or ______

Answer 3

Humans or horses

Question 4

Equine

Answer 4

Equine herpesvirus type 1
- rhinopneumonitis (respiratory, reproductive)
Equine herpesvirus type 2
- pharyngitis of young horses
Equine herpesvirus type 3
- coital exanthema
Equine herpesvirus type 4
- rhinopneumonitis (respiratory, reproductive)

Question 5

Canine

Answer 5

Canine herpesvirus

- fatal hemorrhagic disease of pups

Question 6

Feline

Answer 6

Feline viral rhinotracheitis
- URT disease
Feline herpesvirus 1
Feline urolithiasis virus, feline herpesvirus 2
- experimental, urolithiasis resulting in uremia

Question 7

Avian

Answer 7

Infectious laryngotracheitis virus
- URT disease
- bleed to death in the trachea
Marek's disease virus
- oncogenic, neural, ocular, visceral lymphomatosis
Duck plague virus
- enteric, respiratory, CNS
Herpesvirus infection of pigeons
- coryza, laryngeal and pharyngeal ulcers

Question 8

Human, primates

Answer 8

Herpes simplex virus type 1
- oral blister
Herpes simplex virus type 2
- genital blisters
- reportable!
Herpes zoster
- chicken pox, shingles
Epstein barr virus
- mononucleosis, chronic fatigue syndrome, oncogenic 
Herpes simiae "B" virus
- old world monkeys: epithelial blisters
- humans: fatal encephalitis

Question 9

Fish

Answer 9

Channel catfish virus

- mortality in young fish

Question 10

Herpes vaccines are available for

Answer 10

• bovine
• porcine
• feline

Question 11

Humans zoster is a genetically modified form of ______

Answer 11

Porcine

Question 12

What is the difference between types 1 and 2?

Answer 12

DNA dependent polymerase operates and different temperatures

Question 13

What step of viral replication causes viral eclipse?

Answer 13

Uncoating

- no evidence of viral particle can be seen in transmission electron microscopy

Question 14

Recrudescence

Answer 14

Re-establishment of productive infection

- viral particles are produced

Question 15

Release

Answer 15

Results in cytocidal infections or persistent or oncogenic infections

Question 16

DNA characteristics of herpesvirus

Answer 16

Double stranded, linear, positive sense, single segment

Question 17

Virion

Answer 17

• enveloped
• icosahedral
• 162 capsomeres

Question 18

Nucleic acid

Answer 18

80-150x10^6 molecular weight

- can produce >20 proteins

Question 19

Where does budding occur?

Answer 19

At the inner lamella of the nuclear membrane

Question 20

Herpesvirus can occur in which host type?

Answer 20

Warm, cold blooded, and invertebrate animals

- >500 known herpesviruses

Question 21

Some herpesviruses are ______

Answer 21

Neoplastic

- oncogenic

Question 22

Transmission

Answer 22

Primary contact with a moist mucosal surface

- transplacentally, intrapartum, lactogenic, transfusions, transplants, air, and water

Question 23

Many herpesviruses cause ______ infections

Answer 23

Fetal

• type of placentation makes no difference
• fetal or embryonic deaths occur
• MLV vaccines cause abortions in all animals

Question 24

Alphaherpesvirinae

Answer 24

• host range: variable in vivo and in vitro
• reproductive cycle: short
• CPE: rapid spread leading to mass destruction of cells
• latency: frequent, no exclusively in ganglia

Question 25

Betaherpesvirinae

Answer 25

Ex: feline urolithiasis virus

• host range: narrow in vivo, species specific
• repro cycle: long
• CPE: slow, progressive lytic foci, cytomegalia, IC and IN inclusions
• latency: in epithelial glands of secretory glands, RES, kidney, salivary and adrenal glands

Question 26

Gammaherpesvirinae

Answer 26

Ex: EBV, MCF, MDV

• host range: in vivo is limited to taxonomic orders, in vitro is limited to lymphoblastoid cells (B and T cells)
• repro cycle: variable
• CPE: variable
• latency: frequent in B and T cells

Question 27

Herpesvirus latency occurs following _______

Answer 27

Uncoating of virus in cells

Question 28

Why does viral recrudescence occur?

Answer 28

• fever
• concurrent infection
• stress (affective and physical)
• UV radiation
• immune suppression
• drug therapy

Question 29

Episome formation

Answer 29

Small, circular closed pieces of DNA that are not inserted into host chromosomes
- creates sticky ends so gene exists as a plasmid

Question 30

What is needed for viral recrudescence and pathogenicity to occur?

Answer 30

Thymidine kinase

- TK negative cell lines do not show CPE

Question 31

Insertion into host chromosome

Answer 31

Occurs at germ line, resulting in somatic cell oncogenesis and teratogenesis
- requires restriction endonuclease enzyme that cleaves DNA at palindromic sequences = sticky end exposure

Question 32

Primary infection by HSV-1

Answer 32

Clinical symptoms in peripheral and CNS, URT, and GIT

• leading cause of corneal blindness
• BHV-1 similar biological properties

Question 33

Latency of HSV-1 and BHV-1 is established in _______

Answer 33

Sensory neurons of trigeminal ganglia

Question 34

LAT and LR gene

Answer 34

Responsible for latency in HSV and BHV

• inhibit apoptosis
• viral transcripts that are abundantly transcribed in latency infected neurons (regulate latency)

Question 35

Chromosomal changes

Answer 35

Mitotic mechanism defects
- nucleolar persistance: herpes
- change in number: reovirus and parvovirus
Chromosome breaks
- chromatid
- chromosome
- puverization: SV40, parvovirus

Question 36

Organogenesis

Answer 36

Development of organs in the fetus

- stage of gestation most susceptible to malformations

Question 37

What type of congenital infection occurs only with persistent infection of germinal epithelium?

Answer 37

Trans-ovarian

Question 38

Morula infection

Answer 38

Occurs thru endometrial secretions

• receptors are changing/developing at this stage
• zona pellucida is not present
• important for international trade!
• can be infected by herpes, blue tongue, parvo, paramyxoviruses

Question 39

Semen

Answer 39

All viruses found in seminal fluids

- only retroviruses infect sperm cells

Question 40

Why is the placenta not an effective barrier to viruses?

Answer 40

Numerous distended intracellular spaces