Paramyxoviridae Part 1

Question 1

What is the function of the attachment spike protein of Paramyxoviruses? A. Mediates fusion of the virus envelope with the cell membrane of the host B. Attachment of the virus to host cell C. Elicitation of neutralizing antibodies and protective immunity D. B and C

Answer 1

D.

Question 2

The following are correct about Paramyxoviruses EXCEPT: A. Helically symmetrical nucleocapsid of a “herringbone” shape B. Double-stranded, negative sense RNA genome C. Pleomorphic virions (filamentous or spherical) D. Virions covered with large glycoprotein spikes

Answer 2

B. it is SINGLE-stranded linear negative-sense RNA

Question 3

The following genera have Neuraminidase and Hemagglutinin as their attachment proteins: A. Morbillovirus, Respirovirus, and Avulavirus B. Pneumovirus, Metapneumovirus, and Henipavirus C. Metapneumovirus, Respirovirus and Avulavirus D. Respirovirus, Avulavirus, and Rubulavirus

Answer 3

D.

Question 4

T or F: Henipaviruses, Pneumoviruses, and Metapneumoviruses have a G protein as their attachment spike protein.

Answer 4

T

Question 5

The following virus genera can hemagglutinate red blood cells: A. Rubulaviruses and Avulaviruses only B. Rubulaviruses, Avulaviruses and Respiroviruses only C. Rubuloviruses, Avulaviruses, Respiroviruses, and Morbilloviruses only D. All of the above plus Henipaviruses, Pneumoviruses, and Metapneumoviruses.

Answer 5

C. These are all the genera that have Hemagglutinin; Henipa-, Pneumo- and Metapneumo- have the G protein and do not exhibit hemagglutination.

Question 6

T or F: The fusion protein is present in all genera of Paramyxoviruses, and is dependent upon a low pH for optimal fusion of virus envelope to host cell membrane.

Answer 6

False; It is pH- INDEPENDENT!!!!

Question 7

Which of the following virulence factors plays a key role in establishment of persistent infection by way of evasion of the host immune response? A. Glycoprotein spike B. Matrix protein C. Fusion protein D. Transcription complex

Answer 7

C. Fusion protein; this results in syncytium formation (cell fusion) and cell-cell spread of viruses that more easily evades immune responses.

Question 8

Which of the following elicit neutralizing antibody formation? A. Glycoprotein spike B. Matrix protein C. Fusion protein D. Transcription complex E. Both A and C

Answer 8

E. Both the attachment spike protein and the fusion protein elicit neutralizing antibody.

Question 9

Which of the following are MISMATCHED for Paramyxoviruses? A. Matrix protein: virion release and spread B. Spike protein: induction of protective immunity C. Nucleoprotein: protection of genomic RNA D. Transcriptase complex: L protein, cysteine-rich protein, phosphoprotein E. All of the above are correct

Answer 9

A. Matrix protein helps with virion stability

Question 10

The inclusion bodies of Paramyxoviruses are of the type: A. Eosinophilic, cytoplasmic B. Eosinophilic, intranuclear C. Basophilic, cytoplasmic D. Both A and B are correct

Answer 10

D. The genus Morbillovirus members all have intranuclear eosinophilic IBs, but the rest of the family has cytoplasmic eosinophilic IBs

Question 11

Which of the following viruses is implicated in Shipping Fever in cattle? A. Bovine Respiratory Syncytial Virus B. Bovine Parainfluenza Virus 3 C. Mannheimia Hemolytica Virus D. B and C only E. A, B, and C.

Answer 11

B. Bovine Parainfluenza Virus 3 I like to think of it like this: Bovine parainfluenza is to Shipping Fever as Canine parainfluenza is to kennel cough

Question 12

T or F: Newcastle disease is an Avulavirus that was first discovered in Java, Indonesia, has profound economic impact, and is divided into 5 subtypes based upon differences in its surface antigens.

Answer 12

False! All true except the 5 types (pathotypes) are based upon variations in virulence (non-pathogenic to extremely pathogenic)

Question 13

T or F: Virulent Newcastle Disease (vND) classification consists of lentogenic strains, mesogenic strains, and velogenic strains.

Answer 13

False! Only mesogenic and velogenic

Question 14

Which of the following is mismatched for Newcastle Dz: A. Asymptomatic: enteric, pathotype 1 B. Lentogenic: less virulent, respiratory, pathotype 2 C. Mesogenic: Respiratory signs, 25% mortality, decreased egg production, pathotype 3 D. Velogenic neurotropic: Up to 100% mortality, respiratory signs, torticollis, paralysis, GI hemorrhages, pathotype 5 E. Velogenic viscerotropic: up to 100% mortaility, respiratory signs, GI hemorrhages, head/neck edema, greenish diarrhea, pathotype 4

Answer 14

D. Velogenic neurotrophic will have all of these signs EXCEPT GI hemorrhage, which is distinct for the viscerogenic form.

Question 15

You have a flock of chickens that are suffering from neurological signs, and many have died. You have isolated Newcastle disease on PCR, but now you must determine what level of virulence you are dealing with. You: A. Do immunofluorescence staining of tracheal smears to look for certain types of antibodies. B. Do a CAM inoculation culture, then inject the virus intracranially in neonatal mice, judging virulence by how fast they die. C. Do an intracerebral pathogenicity test on day-old chicks and find that 0.7 or higher is a more virulent strain and less than 0.7 is a less virulent strain D. Look for the presence of a specified amino acid motif at the cleavage site of F protein precursor. E. Either C or D.

Answer 15

E.

Question 16

T or F: If you want to vaccinate your flock of broilers or layers with oil-adjuvanted inactivated vaccines for Newcastle disease, you want to make sure they have been previously vaccinated with a live lentogenic strain vaccine.

Answer 16

True.

Question 17

T or F: Fowlpox and turkey herpesvirus vectored vaccines are one type of vaccine available for Newcastle virus.

Answer 17

True

Question 18

Which of the following viruses produces conjunctivitis in humans? A. Peste de petits ruminants virus B. Bovine Parainfluenza Virus 3 C. Newcastle Disease Virus D. Human Morbillovirus

Answer 18

C.

Question 19

Which of the following is FALSE regarding Canine Parainfluenza Virus 5? A. It was originally called CPiV-2, but was found to be antigenically similar to Simian virus-5, so the nomenclature was changed to CPiV-5. B. It is in the genus Morbillovirus C. It is among the pathogens causing the Kennel Cough complex D. It is spread via aerosol microdroplet E. It causes destruction to ciliated epithelial cells of the respiratory tract.

Answer 19

B. It is in the genus Rubulovirus ***Dogs are practically humans, and when we cough so much our faces get really red. Hence, the Rubulo part.

Question 20

Which of the following are INCORRECT regarding Canine Distemper Virus? A. It is in the genus Morbillovirus B. It can survive in the environment for several weeks if the weather is warm C. At least 10 different lineages have been identified, based on differences in Hemagglutinin gene. D. The virus can infect wild felidae and even pandas E. Infection is usually from droplet inhalation, but transplacental transmission has been reported.

Answer 20

B. It is the opposite! The virus can survive several weeks if the temperature is just above freezing (0-4C) but will not persist in a cool or warm environment once infectious animals have been removed.

Question 21

T or F: Strains of Canine Distemper Virus vary in their pathogenicity, with strains such as Snyder Hill, A75/17, and R252 being very highly virulent and neurotropic.

Answer 21

True. He seemed to think this was important. I don’t have a good way of memorizing these strains, so hopefully he does not try to throw in weird #s and trick us. :/

Question 22

The Canine Distemper Virus replicates in the following cells: A. B and T lymphocytes B. Neurons C. Epithelial cells D. Macrophages E. All of the above

Answer 22

E. All of the above.

Question 23

Which of these is INCORRECT regarding the Pathogenesis of Canine Distemper Virus? A. The virus first replicates in macrophages in the URT and spreads to tonsils and regional LNs B. During primary viremia, the virus circulates in monocytes. C. After primary viremia, it spreads to lymph tissues such as GALT, mesenteric LNs, and Kupffer cells. D. During secondary viremia, the virus is carried by mononuclear cells. E. Hemotogenous spread to target tissues such as CNS and epithelial cells on day 8-9 depends on the humoral and cell-mediated response of the individual animal.

Answer 23

B. During primary viremia, the virus is specifically carried by B and T lymphocytes. Remember, mononuclear cells= Macrophages, monocytes and B and T cells. These are the cells that carry it in secondary viremia (except macrophages bc they stay in tissue)

Question 24

A dog comes into your clinic with neurological and upper respiratory signs and you are concerned about Canine Distemper Virus. Which of the following titer results will make you the most alarmed? A. Antibody Titer on day 9= 1:400, Day 14= 1:1200 B. Ab titer on day 8= 1:200, day 12= 1:800 C. Ab titer on day 9=1:45, day 14= 1:90 D. Ab titer on day 8=1:94, day 14= 1:290

Answer 24

C. At day 8-9, you should see >1:100 to know the dog is probably going to clear the virus At day 14, if you still see

Question 25

Which of the following is NOT TRUE with regards to neurological signs of CDV in dogs? A. Dogs with anti-envelope antibody will be far less likely to develop CNS signs B. CNS invasion is based on magnitude of viremia C. Acute encephalitic form is when the virus replicates directly in CNS tissue and causes an acute inflammatory demyelination of astroglial and microglial cells. D. Subacute-chronic encephalitic form is when the demyelination is not caused by virus replication but by the immune response and will be characterized by reduced viral antigen expression and perivascular cuffing

Answer 25

C. Everything about the statement is correct except that it is a NON-inflammatory demyelination.

Question 26

T or F: “Late signs” of Canine Distemper Virus will generally be seen in old dogs with a competent immune system, and will be characterized by hyperkeratinized nasal plana and footpads, and could accompany progressive ataxia and headpressing.

Answer 26

True. The progressive ataxia and headpressing signs are associated with “Old Dog Encephalitis,” a rare but reported condition in old dogs that are immunocompetent and sometimes have absolutely no history of earlier acute or subacute disease.

Question 27

T or F: Old Dog Encephalitis is a rare manifestation of Canine Distemper Virus that is characterized by progressive inflammation of grey matter of the cerebral hemispheres and brainstem that can occur in immunocompromised elderly dogs chronically afflicted by clinical disease caused by CDV.

Answer 27

False! ImmunoCOMPETENT individuals that have never shown any signs in the past can present with this condition.

Question 28

Which of the following clinical signs are NOT correct for Canine Distemper Virus: A. Transient fever 3-6 days post-infection due to lymphopenia B. 2nd febrile response due to profound leukopenia C. Mucopurulent nasal discharge D. Vomiting and/or Diarrhea E. Hyperkeratosis of footpads and nose, often with neurological signs F. All of the above are true.

Answer 28

F. All true.

Question 29

T or F: In Canine Distemper Virus, encephalitis may occur along with systemic disease (GI, respiratory), after the systemic signs subside, or occur even if systemic signs never manifested.

Answer 29

True!

Question 30

T or F: “Chewing gum fits” is going to be on the exam, and it is a classic neurological sign for Canine Distemper Virus

Answer 30

TRUE!!! Know chewing gum fits!!!

Question 31

T or F:

Immunofluorescence Assay or Reverse Transcriptase PCR are recommended methods of diagnosing Canine Distemper Virus

Answer 31

True.

I dunno why, because I didn’t know CDV had RT, but ok whatever.

Question 32

T or F:

Administration of modified-live vaccines for Canine Distemper Virus will not tend to be neutralized by maternal antibodies, and would thus be preferable to the measles virus vaccine, which will interfere with maternal antibody

Answer 32

False! It is the opposite.

The measles would be used if they are on the younger side and you are worried about maternal antibody still being present (<8 wks of age), whereas if they are older or you are sure they did not get colostrum, then you can go for the MLV.

Adults=MLV

Young pups=measles virus vaccine

Question 34

T or F:

Bovine Parainfluenza Virus-3 is in the genus Pneumovirus, and is characterized by acidophilic cytoplasmic inclusion bodies and syncytium formation

Answer 34

False!

All is true except that BPiV-3 is part of Respivirus genus, which is under subfamily Paramyxovirinae.

Pneumovirus is under subfamily Pneumovirinae and includes Bovine Respiratory Syncytial Virus!

Question 35

T or F:

Syncytia formed by Paramyxoviruses are multinucleated cells that enable viral evasion of the immune system and can survive long periods in the host.

Answer 35

False!

They are defective and cannot survive for long periods!