Exam III (Virology IP6)

C

a herd of cattle had been experiencing abortions one month after a respiratory disease outbreak; the most likely etiology is....?

A. BRSV

B. rinderpest virus

C. bovine herpesvirus 1

D. bovine rotavirus

respiratory

aerosol, droplets, and direct contact are all important for transmission of ____________ diseases

epithelial

most respiratory viruses have tropism for respiratory ____________ cells

shedding

viral _____________ occurs by breathing, coughing, and sneezing with respiratory viruses

latent

alpha herpesviruses cause (latent/persistent) infections

persistent

BVD virus causes (latent/persistent) infections

preclinical

_____________ viral shedding occurs with many respiratory viruses (i.e. often shedding the virus before clinical signs appear)

localized

many of the respiratory viruses are predominantly (localized/generalized) infections; only transient viremia

viscous

within the mucociliary escalator, the top layer of the bilayered mucus is more (viscous/aqueous)

aqueous

within the mucociliary escalator, the bottom layer of the bilayered mucus is more (viscous/aqueous)

mucociliary

many respiratory viruses cause failure of the ___________ transport system, resulting in bacterial infection and pneumonia

interstitial

BRSV infection of alveolar pneumocytes causes ____________ pneumonia

syncytial

bovine respiratory virus infects pneumocytes in alveoli of the lung to form __________ cells

alpha herpesviruses

enveloped dsDNA viruses that result in a latent infection within the sensory ganglia

lytic cycle

a viral reproductive cycle in which copies of a virus are made within a host cell, which then bursts open, releasing new viruses

latent cycle

a viral life cycle in which the virus attacks a cell and then remains inactive for a long period of time before continuing the lytic cyle

reactivation

_____________ of alpha herpesviruses involves a switch from latent >> lytic cycle of infection

influenza viruses

enveloped, segmented RNA viruses infects a wide variety of cells to cause a generalized infection

A

influenza (A/B/C) viruses are pathogen of birds, horses, dogs, swine, and humans

antigenic drift

influenza viruses undergo __________ _________ (within viral antigen genes) to escape detection by existing antibodies

antigenic drift

may be responsible for the large number of serologically distinct strains of many viruses

antigenic shift

influenza viruses also undergo _____________ _____________ which involves reassortment of segments of the viral genome

antigenic shift

____________ __________ is responsible for the most severe influenza epidemics

under

there is a good chance we are (under/over)-diagnosing bovine respiratory diseases due to timing of testing and viral shedding

true

true/false: it is often difficult to detect the virus once the bronchopneumonia is severe enough to observe

true

true/false: stress, weaning, transport, and crowding increase the chance of viral infection

bacterial

the damaging effects caused by viral infections to the respiratory tract predispose animals to developing __________ bronchopneumonia (BRDC organisms, the big 4)

infectious bovine rhinotracheitis (IBR)

disease caused by bovine herpesvirus 1; causes a latent infection in peripheral and central nerve ganglia

1

how many serotypes are there of bovine herpesvirus 1 (that causes IBR)?

BHV-1 (1.1 and 1.2)

which serotype subtype of bovine herpesvirus 1 is associated with respiratory and genital disease in cattle?

BHV-5

which bovine herpesvirus is associated with encephalitis in cattle?

true

true/false: there are alphaviruses serologically related to BHV-1 in deer, reindeer, goat, and elk

false (most are seropositive)

true/false: most cattle are seronegative for bovine herpes virus 1 (IBR)

respiratory

the (respiratory/genital/encephalitis) form of IBR is the most common found in feedlots and with unvaccinated cattle

weaning

outbreaks of IBR (caused by BHV-1) are most common in cattle around the time of ____________

stress

after establishing latency in sensory ganglia, reactivation and shedding of IBR are often associated with ____________

conjunctivitis

BHV-1 infects the respiratory epithelium, but the infection can also spread to the eyes to cause _____________ via the lacrimal ducts

late (6-8 months into gestation)

abortion usually follows an IBR outbreak in a herd and usually occurs in (early/late) gestation

venereal

___________ forms of BHV infection include formation of mucosal erosions or ulcers in the vagina, on the penis, and on the prepuce

false (BHV-5)

true/false: BHV-1 can cause ulcerative rumenitis and enteritis

fibrinopurulent

necrosis of mucosal epithelium with an BHV-1 infection can appear as an upper respiratory tract infection with a ________________ exudate (due to bacterial infection)

true

true/false: multifocal necrosis can be seen in multiple organs of aborted fetuses with an BHV-1 infection

nasal swab

the best sample for BHV-1 testing is a PCR test run from a ________ ________

intranasal

when possible, it is best to use the (parenteral/intranasal) vaccine to protect against BHV-1 because it stimulates systemic and local mucosal immunity

true

true/false: the newer MLV for BHV-1 is generally safe for pregnant cows who have had the same or similar vaccine before

inactivated (killed)

in contrast to MLVs, _____________ vaccines do not cause abortions or latency, but they are not as efficacious in inducing immunity

false (neither can do this!)

true/false: MLVs and killed vaccines can both protect cattle against the establishment of a latent infection with a wild type virus

false

true/false: vaccination prevents future shedding of latent wild type virus that was present at the time of vaccination

false (not unless a DIVA or marker vaccine)

true/false: we can detect the difference between naturally infected vs. vaccinated cattle with BHV-1 (IBR)

short

immunity to infection with bovine respiratory syncytial virus is (short/long) term

2

how many serotypes exist for BRSV?

6 months

calves under ____ ___________ of age are more commonly affected with BRSV

BRSV

lesions of this virus in cattle are collapsed lungs, emphysema, necrotizing bronchiolitis, and interstitial pneumonia; usually an acute disease

IHC

PCR from nasal swabs is used to detect BRSV, as well as ________ on tissue samples

2

in a study, calves vaccinated with BRSV were ____-times less likely to be treated for chronic respiratory disease

bovine parainfluenza virus 3

virus in cattle that causes transient clinical disease; most important role is predisposing the cattle to bacterial pneumonia

D

which of the following does NOT cause upper respiratory infections in the cat?

A. feline calicivirus

B. influenza virus

C. feline herpesvirus-1

D. feline panleukopenia virus

feline infectious respiratory disease

infectious respiratory disease in cats that is caused by a variety of bacteria and viruses; clinical signs overlap and are often indistinguishable

feline herpesvirus 1

replication of this virus causes necrosis and exfoliation of cells and results in rhinitis, conjunctivitis, and ulcerative keratitis; predisposes to secondary bacterial infections as well

feline calicivirus

virus that causes rhinitis, conjunctivitis, gingivitis, stomatitis, and pneumonia; recovered animals are persistently infected and shed virus in nasal secretions and feces

A

animals with feline herpesvirus 1 are:

A. latently infected

B. persistently infected

B

animals with feline calicivirus are:

A. latently infected

B. persistently infected

80

feline herpesvirus-1 & feline calicivirus account for ____% of feline upper respiratory disease (as primary etiologic agents!)

false (cats don't have one that is endemic like dogs, but they can still get an influenza virus infection/disease)

true/false: cats have an endemic influenza that is maintained among cats

sensory ganglia

feline herpesvirus-1, like other alpha herpesviruses, establish latent infections in the ____________ ___________

feline herpesvirus 1

virus that replicates in the nucleus and forms intranuclear inclusion bodies; causes feline viral rhinotracheitis

1 (but several strains)

how many serotypes exist for feline herpesvirus 1?

aersols

FHV-1 is transmitted through direct contact (via oronasal and ocular secretions) as well as from __________ from infected cats

true

true/false: FHV-1 typically causes disease in kittens and unvaccinated cats

cytolytic

FHV-1 is a _________ virus which causes ulceration in the upper respiratory mucosa and cornea; also associated with immune mediated stromal keratitis

ocular

FHV-1 is primarily an upper respiratory and ___________ pathogen

FHV-1

__________ in the upper respiratory tract may permanently damage the turbinates, predisposing to chronic rhinitis and sinusitis

FHV-1

corneal ulcers would most likely be caused by (FHV-1/FCV)

FCV

oral ulcers would most likely be caused by (FHV-1/FCV)

fever

the distinguishing features of some FHV-1 infections is a high _________ and corneal ulcers

ulcers

the distinguishing feature of some FCV infections is ________ on the tongue, palate, and pharynx

false (often clinical signs overlap)

true/false: it is easy to differentiate the clinical signs from FCV and FHV-1

yes (90% reduction in clinical signs; killed and MLV available)

yes/no: feline herpesvirus-1 is a core vaccine

felidae

feline calicivirus can infect all members of ____________; common in young cats (

environment

feline calicivirus persists for a long time in the ______________, so fomites are an important means of transmission (though also aersols and direct contact as well)

FCV (FHV-1 easily destroyed by disinfectant and environment)

which is more stable in the environment—FHV-1 or FCV?

true

true/false: cats infected with feline calicivirus can become lifelong shedders of the virus

antigenic drift

_____________ __________ is often the cause of the continuing emergence of viruses with different phenotypic properties such as virulence

feline calicivirus

virus that is most likely to blame for an acute oral and upper respiratory tract infection in cats

epithelial cells

feline calicivirus replicates in ____________ ___________ (of the oral cavity, upper respiratory tract, and pneumocytes)

FCV

(FHV-1/FCV) usually causes milder disease

VS-FCV (virulent systemic)

a strain of FCV that has been reported to cause a generalized infection and an acute, fatal, systemic disease (death due to DIC, pancreatitis, hepatic and enteric necrosis)

tropism

VS-FCV strains have acquired mutations that enable expanded cell ____________ that infects macrophages, endothelial cells, hepatocytes, and pancreatic cells

VS-FCV

strain of FCV that can cause fever, SQ edema, ulcers on the digits, hemorrhaging, and thromboembolisms

RT-PCR (reverse transcriptase-PCR)

most common diagnostic tool for feline calicivirus

false (most cats have antibody whether through natural infection or vaccines)

true/false: serology can be helpful in diagnosing FCV

yes

yes/no: feline calicivirus is a core vaccine

false (not equally protective with the VS-FCV strain)

true/false: most vaccines used for FCV protect against the majority of isolates equally

nasal

studies suggest that the (injectable/nasal) form of the FCV vaccine provides more rapid protection against the virus

false

true/false: vaccination against FCV protects against the carrier state and viral shedding

true

true/false: kittens are easily infected by queens with FHV-1 after triggering a latent infection with parturition and lactation

FCV

synovitis and lameness is more suggestive of (FHV-1/FCV)

canine infectious respiratory disease

a complex respiratory syndrome in dogs that is usually caused by infection with a combination of bacterial and/or viral agents; mixed infections can often have a synergistic effect

canine distemper virus

some pathogens are virulent enough to cause CIRD as the sole infectious agent (i.e. ___________ __________ ___________)

true (shedding preclinical and subclinically)

true/false: many of the causative viral pathogens for CIRD can be shed in the absence of clinical disease