Lecture 12 - Respiratory Virology 2

Question 1

PRDC is a multifactoral disease caused by what 3 things

Answer 1

1. bacteria
2. virus
3. management/environment

Question 2

what are the ways PRRSV is transmitted

Answer 2

1. aerosolized
2. sexual transmission
3. fomites

Question 3

T/F: PRRSV has a very high mutation rate

Answer 3

TRUE

Question 4

what is the site of infection and target of PRRSV

Answer 4

infection: lung or bulbourethral gland

target: macrophages

Question 5

T/F: there have been no vaccines developed to address PRRSV shedding in semen

Answer 5

FALSE

Question 6

what does PRRSV induce

Answer 6

immunosuppression

Question 7

what are the clinical signs of PRRSV

Answer 7

• fever
• anorexia
• respiratory distress
• pneumonia
• SMEDI (abortions and stillbirths)

Question 8

inactivated vaccines

Answer 8

low cross-protection; usually strain isolated from herd

Question 9

live vaccines

Answer 9

some cross-protection; potential recombination

Question 10

T/F: genetically modified pigs against PRRSV have been made but are not common

Answer 10

TRUE

Question 11

Porcine respiratory coronavirus (PRCV) is a mutant of

Answer 11

Transmissible gastroenteritis virus (TGEV)

Question 12

T/F: antibodies against ORCV and TGEV are cross-reactive

Answer 12

TRUE

Question 13

Pseudorabies/Aujeszky’s is present in what populations

Answer 13

eradicated from commercial swine but endemic in feral swine populations

Question 14

what are the natural and accidental hosts of pseudorabies

Answer 14

natural = swine
accidental = dogs, cats, horse, sheep, goats, rabbits

Question 15

outcome of pseudorabies is dependent on what

Answer 15

1. age
2. immune status

Question 16

Young pigs infected with pseudorabies undergo

Answer 16

multiorgan neonatal disease with high mortality

Question 17

what is the primary agent in PRDC

Answer 17

porcine circovirus

Question 18

what is the respiratory secondary infection that arises from PCVD

Answer 18

porcine respiratory disease complex

Question 19

describe nipah virus

Answer 19

• morbillivirus
• respiratory (cough) and neurologic
• zoonotic

Question 20

what are paramyxoviruses

Answer 20

1. Newcastle
2. parainfluenza III
3. bovine respiratory syncytial virus
4. rinderpest
5. canine distemper

Question 21

how are paramyxoviruses transmitted

Answer 21

1. aerosolized secretions
2. ingestion of contaminated feed/water
3. secretions/excretions

Question 22

describe Newcastle disease

Answer 22

• infects avian spp.
• transmission by inhalation of aerosols and ingestion of contaminated feed
• initially in mucosal epithelia then systemic

Question 23

T/F: Newcastle syndromes are dependent on strain

Answer 23

TRUE

Question 24

lentogenic

Answer 24

mild respiratory disease

Question 25

mesogenic

Answer 25

moderate systemic infection (resp. and GI)

Question 26

velogenic or exotic

Answer 26

severe systemic infection

Question 27

what is the control for Newcastle

Answer 27

modified live vax

Question 28

describe infectious laryngotracheitis

Answer 28

respiratory disease categorized by dyspnea and expectoration of blood decreased egg production

Question 29

what is the pathogenesis of infectious laryngotracheitis

Answer 29

1. aerosol exposure 2. lytic infection of tracheal epithelium 3. necrotic cells = blood in tracheal lumen 4. asphyxiation and death

Question 30

T/F: infectious laryngotracheitis is always treated by vaccine

Answer 30

FALSE - biosecurity in free areas, vaccines in endemic areas

Question 31

describe the infectious bronchitis virus

Answer 31

- highly contagious in chickens - infects trachea but can spread to kidneys + ovaries - reduced egg yield and quality - MLV or inactivated

Question 32

describe avian metapneumovirus

Answer 32

- 3 to 12 weeks of age - facial pruritus, s+, nasal/eye discharge - drop in egg production - can resolve given no complications

Question 33

describe shipping fever

Answer 33

viral respiratory infection with secondary bacterial infection and stress controlled by MLV

Question 34

what disease, termed cattle plague, was "eradicated"

Answer 34

rinderpest

Question 35

what is the pathogenesis and control for rinderpest

Answer 35

pathogenesis: oropharyngeal lymph infection, systemic, fever, erosions, bloody d+ control: surveillance, culling, restrictions and regulations, intense vax

Question 36

what are the top 3 disease manifestations of bovine herpesvirus 1

Answer 36

1. respiratory disease 2. abortion 3. multiorgan neonatal infection

Question 37

why may we not give an MLV for bovine herpesvirus 1

Answer 37

if the cow is pregnant this may induce abortions

Question 38

what virus causes an inapparent or severe fatal form of disease based on species

Answer 38

malignant catarrhal fever virus (gammaherpesvirus)

Question 39

T/F: fatal systemic infections of gammaherpesvirus occurs in natural hosts

Answer 39

FALSE

Question 40

what are the clinical signs of gammaherpesvirus

Answer 40

- fever - ulceration - nasal/ocular discharge - corneal edema - death

Question 41

is there a vaccine for gammaherpesvirus

Answer 41

NO

Question 42

what is visna-maedi

Answer 42

ovine progressive pneumonia common to iceland

Question 43

describe the transmission of OPP

Answer 43

1. inhalation or ingestion of respiratory secretions 2. colostrum to nursing kids

Question 44

what are the clinical signs of OPP

Answer 44

- gradual weight loss - cough - nasal discharge - some CNS symptoms

Question 45

T/F: there is NO treatment for OPP

Answer 45

TRUE

Question 46

T/F: bovine adenovirus is always a respiratory manifestation

Answer 46

FALSE - 10 serotypes create array of infections