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1The main advantage of using virus isolation over the molecular based diagnostic assays such as PCR is that:
- AQuicker
- BCheaper
- CLess equipment/skills
- DDemonstrates presence of live virus
- EImmediate identification via CPE
2Which of these stages in the viral replication cycle is least likely to be targeted by antiviral drugs?
- AAdsorption
- BAttachment
- CUncoating
- DSynthesis
- ERelease
3Viruses posses the following characteristics:
- AContain DNA and RNA
- BHave a nucleus
- CViral nucleic acids generate viral mRNA in host
- DHave ribosomes to synthesise protein in host
- ECan all be cultured in vitro
4Choose the least correct statement regarding the attachment of the virus to the host cell:
- ANecessary for entry
- BDetermines tropism and host range
- CNeeds specific binding to host proteins
- DFollowed by penetration
- ECannot be blocked due to wide range of receptors
5The term "viral virulence" relates to the ability of the virus to:
- Acause disease in natural host species
- Bcause CPE in cell culture
- Ccause disease in humans
- Dspread systemically and infect many tissues
- Ecause disease in a specified host
6Choose the best answer to finish the sentence: Swabs for virological investigation should be collected...
- AInto a commercially available aerobic bacteriological swab -the medium provided with these swabs is suitable for both viral and bacteriological samples
- BInto a commercially available anaerobic bacteriological swab -the medium provided with these swabs is suitable for both viral and bacteriological samples
- CDry into a sterile container (e.g. red top blood tube), so that any viruses present will not be diluted by the medium
- DInto a viral transport medium, which contains proteins to stabilize the virus and antibiotics to prevent bacterial growth
- EInto a sterile EDTA blood tube if the swab contains bloody discharge, so that it won't coagulate during transport to the laboratory
7The samples for virological investigation should be transported to the laboratory
- AAs soon as possible, preferably within 24 hours of collection. The samples should
be put in a freezer immediately after collection and then thawed when ready for transport. The samples should be transported cold with ice packs. - BAs soon as possible, preferably within 24 hours of collection. The samples should be kept cold, but not frozen after collection and during transport.
- CWithin a week of collection, providing they are kept in a fridge
- DAs soon as possible, preferably within 24 hours of collection. If the samples are transported to the laboratory soon after collection there is no need to maintain the cold chain during transport
- EAny time after collection as long as the samples are maintained in the fridge. If the samples were collected using sterile technique all viruses will survive in the fridge for extended periods of time.
- AAs soon as possible, preferably within 24 hours of collection. The samples should
8Which of the following statements about virus size and complexity is most true?
- AThe smallest viruses are smaller than viroids
- BThe largest viruses are about as complex as Escherichia col
- CThe largest viruses can replicate independently of living cells.
- DThe smallest viruses consist only of protein
- EThe smallest viruses are larger than prions
9Which of the following is least useful as a basis for classifying viruses into families?
- ADNA or RNA genome
- BDouble-stranded or single-stranded genome.
- CIntranuclear or intracytoplasmic inclusion bodies
- DHelical, icosahedral, or complex structural symmetry
- EEnveloped or non-enveloped virions
10Which of the following stages in the virus replication cycle is the drug Tamiflu thought to target?
- AAdsorption
- BAttachment
- CUncoating
- DSynthesis
- ERelease
11Soluble CD4 has been used experimentally as an anti-HIV drug and may yet prove useful in veterinary medicine. Which of the following stages in the virus replication cycle is it thought to target?
- AAdsorption
- BAttachment
- CUncoating
- DSynthesis
- ERelease
12Which of the following is the most commonly and widely used method for the cultivation of mammalian viruses?
- AOrgan cultures
- BExperimental animals
- CPrimary cell cultures
- DSecondary cell cultures
- EContinuous cell lines
13A cytopathic effect (CPE) is sometimes observed when cultivating viruses in vitro. Which of the following statements about CPE is least correct?
- ASome kinds of virus cause a characteristic CPE. For example, herpesviruses
tend to cause formation of syncytia - BDead cells, killed by the virus, tend to look large, angular, and paler than
surrounding healthy, uninfected cells - CIt may take weeks for a CPE to develop. Multiple cell passages may have to be done before CPE can be observed
- DSome kinds of virus grow very well in cell culture but cause no CPE whatsoever
- EIf CPE develops very rapidly, it may be difficult to distinguish it from cytotoxicity due to a toxic substance in the clinical specimen (i.e., the inoculum)
- ASome kinds of virus cause a characteristic CPE. For example, herpesviruses
14Which of the following are viral non-structural proteins? Choose all correct answers (there may be more than one)
- AIntegrase
- BReverse transcriptase
- CHyaluronidase
- DHexokinase
- EPeplomerase
15Which of the following statements about viral structure are true? Choose all correct answers (there may be more than one)
- AStructural symmetry facilitates virion self-assembly
- BCubic symmetry is a synonym for icosahedral symmetry.
- CIndividual virus families contain viruses of helical or icosahedral symmetry, but
not both - DVirions with complex symmetry have both helical and icosahedral symmetry
- EHelical symmetry is a feature of the viral nucleocapsid, not of the envelope
16Laboratory results of virus isolation are usually available
- AWithin 24-48 hours. This is how long it takes for viral colonies to become visible on agar plates.
- BWithin 2-3 days for positive samples, but it may take up to 1 week for negative samples, as these are typically passaged in the appropriate cells 2-3 times before being reported as negative
- CWithin 1-3 weeks for positive samples, but it may take up to one month or longer for negative samples, as these are typically passaged in the appropriate cells 2-3 times before being reported as negative
- DWithin 24-48 hours, as viruses multiply very fast and typically millions of viruses are produced from one infected cell within hours
- EWithin 1 week for negative samples, but it may take longer for positive samples, as the viruses cultured would have to be further identified
17Which of the following statements about viral genomes is least true?
- AMost DNA virus families have double-stranded genomes.
- BSome RNA viruses have segmented genomes, but there are no DNA viruses with segmented genomes
- CThere are no known RNA viruses with circular genomes
- DDNA virus genomes vary in size much more than do RNA virus genomes
- EThere are no known RNA viruses with double-stranded genomes
18Antiviral drugs inhibit specific steps in viral replication
- AVerdadeiro
- BFalso
19Resistance to antiviral drugs is very rare, as viruses cannot change as rapidly
as bacteria- AVerdadeiro
- BFalso
20Enveloped viruses are typically fragile and easily killed outside their hosts
- AVerdadeiro
- BFalso
21Killed vaccines are safer and as such, killed vaccines are more commonly used in veterinary medicine than live vaccines
- AVerdadeiro
- BFalso
22A single serum sample positive for antibody to a virus indicates that the animal from which the blood was collected had been recently infected with this virus
- AVerdadeiro
- BFalso
23A large sheep farm in central Otago has had problems with scabby mouth in lambs each year for the last 4 years. They do not vaccinate against scabby mouth on this farm. The mostlikely explanation for the recurrent, relatively severe problems on this farm is
- APersistently-infected ewes are acting as a source of the virus to new lambs each year
- BThe virus is maintained in a rodent population on this farm and is periodically spread to lambs
- CRams are transmitting the virus venereally to ewes and the ewes are passing the infection on to their lambs
- DThe pastures and food troughs are contaminated with the virus, which is surviving outside each winter
- EAn unusually hardy virus variant has evolved on this farm
24Which of the following viruses typically produce only localised infections without systemic spread:
- AFeline panleukopenia virus
- BEquid herpesvirus type 1
- CCanine parvovirus
- DOrf virus
- EAfrican swine fever virus
25Which of the following viruses infect invertebrate hosts?
- AAfrican swine fever virus
- BCanine adenovirus type 1
- CFeline herpesvirus type 1
- DOrf virus
- EPorcine circovirus type 2
26A proliferative lesion in the picture below is characteristic of infection
with
- AHerpesv-
- BAdenov-
- CPoxv-
- DCircov-
- EParvov-
27In general, poxviruses can use the following portals of entry
- AFaecal-oral route
- BSkin with compromised integrity (e.g. skin abrasions)
- CRespiratory route (via aerosols)
- DBlood via mechanical vectors
28You are a veterinarian accompanying a large group of sheep that is being shipped from New Zealand to the Middle East in a vessel that has previously been used for the shipment of sheep in other parts of the world. 28 days into the journey, 20% of these sheep have developed fever, generalised, raised skin lesions, and severe systemic illness. So far, about 25% of affected animals have died or required euthanasia on humane grounds. You suspect a viral infection. The most likely differential diagnosis at this stage is:
- AGeneralised orf
- BEctromelia.
- CVariola.
- DContagious ecthyma.
- ESheep pox.
29What kind of vaccine is licensed in New Zealand to prevent Orf?
- AModified live (i.e., attenuated).
- BAdjuvanted, killed whole virus.
- CAdjuvanted, viral subunit.
- DLive, fully virulent virus.
- ERecombinant avipox virus.
30Which of the following poxviruses has an unusually broad host range?
- AMyxoma virus.
- BLumpy skin disease virus.
- CVariola
- DSwinepox
- ECowpox
31You are called to investigate a drop in production levels at a local poultry farm. When you arrive, you notice a large number of misshapen eggs, as shown in a picture below. Infection with which virus should be on your list of differentials?
- APox
- BAdeno
- CParvo
- DHerpes
- ECirco
32Which of the following are characteristic features of poxviruses? Choose all correct answers (there may be more than one).
- AEnveloped DNA viruses.
- BIntracytoplasmic replication.
- CLong-term carrier state after recovery.
- DEvolve more rapidly than most other viruses.
- EComplex structural symmetry.
33Which of the following poxviral diseases is notknown to be zoonotic? Choose all correct answers (there may be more than one)
- ACowpox
- BPseudocowpox
- CBovine papular stomatitis.
- DParapoxvirus infection of red deer in New Zealand.
- EMonkeypox
34Which of the following is the least important reason why it was possible to eradicate smallpox from the world?
- AONE (1)stable serotype of the virus exists.
- BSmallpox has a long incubation period.
- CAnimal reservoir populations are well characterised.
- DSmallpox is easily diagnosed.
- EThe period of infectivity begins after the end of the incubation period.
35Which of the following viruses is leastresistant to adverse environmental conditions?
- ACanine parvovirus.
- BEquid herpesvirus type 1.
- COrf virus.
- DAfrican swine fever virus.
- EBovine papillomavirus.
36Orf virus can be transmitted between susceptible animals via fomites.
- AVerdadeiro
- BFalso
37Poxviruses typically cause localized skin infections.
- AVerdadeiro
- BFalso
38Some poxviruses can establish viremia followed by generalized disease.
- AVerdadeiro
- BFalso
39Poxviruses do not survive well in the environment.
- AVerdadeiro
- BFalso
40Orf virus can infect humans.
- AVerdadeiro
- BFalso
41Myxomatosis causes severe generalised disease in European rabbits, but only
localised benign fibromas in American rabbits- AVerdadeiro
- BFalso
42A kitten with upper respiratory disease is most likelyto be infected with which of the following viruses
- AFeline immunodeficiency virus.
- BFeline herpesvirus.
- CFeline coronavirus.
- DFeline astrovirus.
- EFeline infectious peritonitis virus.
43Choose the least correct statement regarding Pseudorabies:
- AIt is caused by Suid herpesvirus type 1.
- BIn dogs, it presents with clinical signs similar to rabies with incoordination,
paralysis and convulsions - CAdult swine infected with the Pseudorabies virus typically do not develop severe disease, but may abort
- DDogs can become infected via ingestion of infected raw pig meat.
- EIt is a zoonotic disease
44Which of the following viruses is leastlikely to cause neurologic disease in a horse?
- AEquid herpesvirus type 4.
. - BEquid herpesvirus type 1
- CBorna disease virus
- DEastern equine encephalitis virus
- EFeline infectious peritonitis virus.
- AEquid herpesvirus type 4.
45Which of the following viruses is leastlikely to cause neurologic disease in a horse?
- AEquid herpesvirus type 1
- BBorna disease virus
- CWestern equine encephalitis virus
- DEquine influenza virus
- EWest nile virus
46One of the characteristics common to all herpesviruses is their ability to establish latency in their hosts. Choose the best statement describing the relationship between the host and a herpesvirus in a latent stage:
- ADuring latency there is a very limited production of progeny viruses.
- BDuring latency there is no production of progeny viruses, but limited transcription of the viral genome can occur
- CAll herpesviruses establish latency exclusively in neural tissues
- DOnce the virus enters a latent stage, it can be reactivated only if the host becomes re-infected with the same herpesvirus
- EVaccination against herpesviruses is typically effective in preventing development of latency
47Choose the bestoption from the following. Herpesviruses:
- ATypically cause a short illness followed by recovery and elimination of the virus.
- BStimulate solid (possibly life-long) immunity. Recovered animals are refractory to subsequent herpesviral infections.
- CEstablish a life-long infection in their hosts, with a constant low-level production of infectious virus
- DAre very resistant in the environment and as such, are easily transmitted by fomites over extended areas
- ETypically establish a life-long infection due to their ability to become latent.
48You are asked to advise on biosecurity measures to control the spread of
respiratory viruses in a cattery. Which of the following statements is least correct?- AFeline calicivirus and Feline herpesvirus are the two most common respiratory viruses of cats
- BBoth viruses are fragile in the environment and don't survive well outside their hosts.
- CBoth viruses can be transmitted by aerosol.
- DThere are vaccines available for both viruses
- EAsymptomatic infections can occur with both viruses
49Which of the following clinical presentations is leasttypical of herpesviral infection
- AEncephalitis.
- BUlcerative skin lesions.
- CAbortion.
- DUpper respiration disease.
- EPancreatitis.
50One of the characteristics common to all herpesviruses is their ability to establish latency in their hosts. Choose the least true statement describing the effects of latency on diagnosis and control of herpesviral diseases
- ADetection of latently infected animals is difficult, as these animals appear clinically normal and are not shedding the virus
- BLatently infected animals can re-activate the virus when stressed. As such, they can develop herpesvirus-associated disease even if not exposed to a source of an infectious virus (e.g. a clinically sick animal)
- CLatently infected animals can be detected by serological testing, as they are always positive for anti-herpesviral antibody, even though they are not shedding the virus.
- DLatently infected animals are not infectious. However, they do become infectious when they re-activate the virus
- EVaccination against herpesviruses is typically ineffective in preventing development of latency.
51A serum sample from a mare that aborted due to a suspected Equid herpesvirus 1 infection tested positive for EHV-1 antibodies in a virus neutralisation test. Choose the incorrectinterpretation of this result
- AThe positive result confirms that the mare aborted due to EHV-1 infection.
- BThe mare might have aborted due to the EHV-1 infection, but in order to confirm a recent EHV-1 infection a four-fold rise in titre between the acute and convalescent serum samples would have to be demonstrated
- CThe positive result indicates that the mare has been likely exposed to EHV-1 at some point in the past, but tells us little about the timing of infection
- DIt is possible that the mare has never been infected with EHV-1, as the positive serum titre to EHV-1 may have resulted from either vaccination or infection with an antigenically similar virus EHV-4.
- EThe mare has been exposed to either EHV-1 or EHV-4 at some point in the past. These two viruses cannot be distinguished serologically in a neutralisation test.
52Which of the following is leasttrue of Malignant catarrhal fever in New Zealand?
- AIt occurs sporadically
- BIt is caused by Alcelaphine herpesvirus type 1.
- CIt features a characteristic vasculitis.
- DIt is most important in farmed red deer.
- EIt is epidemiologically linked to contact with sheep.
53You are called to investigate an abortion "storm" that is occurring in a mob of heavily-pregnant mares. On close questioning, you learn that a 'new' mare has recently been introduced from another part of the country. Which of the following herpesviral causes should be at or near the top of your differential list?
- AEHV 1
- BEHV 2
- CEHV 3
- DEHV 4
- EEHV 5
54Which of the following disease manifestations is leasttypical of herpesvirus infections in mammals?
- ARespiratory disease
- BHepatitis.
- CCentral nervous system changes.
- DLymphoproliferative disorders.
- EUlcerative skin lesions
55Which of the following statements are trueof alphaherpesviral latency?
Choose all correct answers (there may be more than one)- ADuring latency, virus particles cannot be detected during any routine diagnostic test
- BBecause of latency, measurement of antiviral antibodies is uninformative.
- CThere may be no viral protein whatsoever in the host's body during latency.
- DDuring latency, virus can nevertheless be transmitted from host to host.
- ELatency is most often achieved in nerve ganglia and lymphocytes.
56Which of the following is nota well recognised consequence of equid herpesvirus 1 infection?
- AAbortion.
- BEncephalomyelitis.
- CUpper respiratory disease.
- DGenital mucosal ulcerations.
- EPerinatal foal mortality.
57Following EHV-1 infection, horses develop a life-long immunity to re-infection, but the latent virus can still be re-activated
- AVerdadeiro
- BFalso
58Vaccination against EHV-1 is protective against the neurological form of disease
- AVerdadeiro
- BFalso
59Herpesviruses stimulate solid (possibly life-long) immunity. Recovered animals are refractory to subsequent herpesviral infections.
- AVerdadeiro
- BFalso
60Infection with the Aujeszky's disease virus causes fatal meningoencephalitis in cattle, sheep, dogs, foxes, and rabbits
- AVerdadeiro
- BFalso
61Herpesviruses typically cause a short illness followed by recovery and elimination of the virus
- AVerdadeiro
- BFalso
Informações
- Descrição
- Quiz sobre Sem título, criado por Jordi Hoult em 31-10-2014.
- Autor
- Jordi Hoult
- Idioma
- English
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