Picornaviridae

Question 1

Which of the following is the genomic mRNA protein for Picornaviridae, and which end of the RNA does it bonded to? A. NS3; 3 prime B. VS3; 5 prime C. VPg; 5 prime D. L (large) protein; 5 prime

Answer 1

D. VPg 5 prime

Question 2

Which of the following is FALSE regarding Picornaviridae? A. Single molecule of positive-sense single-stranded linear RNA B. the genome is infectious C. Spherical, enveloped, smooth, round virions. D. Picornaviruses are rapidly cytopathic.

Answer 2

C. Yes spherical, smooth and round, but NON-ENVELOPED ***I think of corn kernels as being kind of spherical, smooth, and hard so they’re naked, not covered in a soft covering…kind of a stretch but I can’t think of anything else

Question 3

There are over 29 genera of Picornavruses, and the difference among them is mainly reflected by ability to be stable under acidic conditions.

Answer 3

True; some are stable in acidic pH, some are not ***I like to eat corn drenched in vinegar sometimes but my friend does not….I dunno kind of a stretch lol

Question 4

The following regions are free of Foot-and-Mouth disease EXCEPT ? A. Caribbean B. North America C. Western Europe D. South America

Answer 4

D. South America Western Europe has occasional epizootics but is still considered virus-free Central America and Oceania are also virus-free

Question 5

Which of the following regions is MISMATCHED with its serotypes of FMD? A. Africa- C, A, O B. South America- C, A, O C. Asia, Middle East, Eastern Europe- O, A, C, Asia-1 D. Africa- C, A, O, SAT-1, SAT 2, SAT 3

Answer 5

A. Africa has C, A, O, SAT 1, 2, and 3 Everyone has CAO, but Africa has the SATs because you need SafarihATs

Question 6

T or F: Horses are especially vulnerable to FMD

Answer 6

False! Horses are resistant to FMD! It is a disease of even-toed ungulates (cloven-footed animals) Horses are very dignified creatures, they would never put their foot in their mouth!

Question 7

T or F: Foot-and-Mouth disease virus is stable at low pH

Answer 7

False; Likes pH 6-9, so doesn’t like too acidic or too basic so any common acid or base could be used as a disinfectant I like to think of it as if you put your foot in your mouth, you don’t want it to taste too acidic or too basic- and it will burn your mouth!

Question 8

T or F: FMD is known to persist in the pharynx of cattle for up to 2 years, sheep for 6 months, and swine for up to a year.

Answer 8

False! Swine do NOT exhibit persistence of virus in their mouth!!!!

Question 9

Which of the following is NOT associated with Apthovirus infection in CATTLE: A. Abortion due to transplacental transmission of virus B. A drop in milk production and excessive salivation are often early signs, followed by tongue vesicles soon after C. Mastitis is a common complication D. Hairy Panters syndrome is a known sequel E. Lameness

Answer 9

A. Abortion does occur in cattle, but it is associated with the febrile state. The virus cannot cross the placenta

Question 10

T or F: Tiger heart is a sequel of Apthovirus infection in young cattle and pigs, and reflects myocardial injury which often causes sudden death

Answer 10

T

Question 11

A common site for severe vesicles seen in FMD for swine include all EXCEPT: A. Snout B. Coronary bands C. Inside of the mouth D. Epithelium of hooves

Answer 11

C. Inside of mouth This is more associated with cattle

Question 12

T or F: It is important to test for antibodies to structural proteins in FMD, because vaccines are made with nonstructural proteins and we want to be able to differentiate vaccinated from unvaccinated animals.

Answer 12

False Vaccines= STRUCTURAL Ag’s (at least in this case) Therefore if you test for antibodies for NONSTRUCTURAL proteins/Ags, your vaccinated animals will not come up positive (DIVA concept of vaccines)

Question 13

T or F: Although Foot-and-Mouth Disease is one of high morbidity and low mortality, it is a notifiable disease, and in disease-free countries, importation of animals from endemic countries is banned.

Answer 13

True

Question 14

Which of the following is the INCORRECT association for Avian Encephalomyelitis? A. AKA Epidemic Tremor B. Caused by a Tremovirus C. Observed in chicks 1-3 weeks old D. Ovarian transmission: Incubation period >11 days E. Fecal-oral transmission: Incubation period 1-7 days F. 2 of the above are incorrect

Answer 14

Incubation for vertical (via egg)= 1-7 days Incubation for horizontal (fecal-oral)= 11 days or more

Question 15

Which of the following histological lesions is characteristic of Avian Encephalomyelitis? A. Perivascular cuffing B. Peripheral neuronal necrosis C. Central chromatolysis of neurons in medulla oblongata D. Central chromatolysis of neurons in the cortex

Answer 15

C. Central chromatolysis of neurons in the MEDULLA There is neuronal necrosis, but in the CNS only, NOT in peripheral nerves

Question 16

A major way to differentiate Avian Encephalomyelopathy from Newcastle Disease is: A. Newcastle Disease has virulent strains that cause high morbidity/mortality in adults, whereas AE only causes neurological signs in young chickens B. Newcastle disease vertical transmission is rare, where it is not for AE. C. AE has characteristic fine tremors of the head/neck D. AE has two distinct syndromes based on age of the bird at infection. E. All of the above

Answer 16

E

Question 17

T or F: Usually birds affected with Tremovirus are destroyed, but if not and they survive infection, they may develop cataract, a blue opacity of the lens and CNS deficiencies.

Answer 17

True

Question 18

The following are signs of Tremovirus in adult laying hens, EXCEPT: A. Drop in egg production B. Deterioration in egg shell quality C. Drop in hatchability due to late embryonic death D. Neurological signs, including fine tremors of the face E. Neither B and D are NOT seen in laying hens

Answer 18

E. You will NOT see defective egg shells or any neuro signs in adult laying hens

Question 19

T/F: Although samples submitted for isolation of virus for Avian Encephalomyelitis cases need to include brain WITH duodenum and pancreas, demonstration of viral antigen in neural or other tissue by IHC or IFA is sufficient for reliable diagnosis.

Answer 19

True ZZZzzzzzZZZZzzzzzz

Question 20

T or F: Vaccines for Avian Encephalomyelitis are often given in combination with Fowlpox vaccines and are administered via spray or drinking water.

Answer 20

False! Wing-web inoculation

Question 21

The following are true for Cardiovirus, EXCEPT: A. It causes the disease Encephalomyocarditis B. It affects swine and wildlife species, including elephants C. the natural hosts are rodents D. Death is usually associated with the focal necrosis of the myocardium, termed “Tiger Heart.” E. All of the above are true.

Answer 21

D. Subacute or acute death is due to MULTIFOCAL necrosis of the myocardium, and it is NOT termed Tiger heart…that’s for Foot-and-Mouth Disease! :)

Question 22

T/F:

Cardiovirus is a cause of reproductive failure in swine, resulting in mummified fetuses, stillbirths, and early-term abortions.

Answer 22

False- everything is correct except the abortions are LATE term (107-111 days gestation)