Final Exam - Rhabdoviridae

Question 1

Rhabdoviridae 4 genera with human and animal pathogens

Answer 1

Lyssavirus, Vesiculovirus, Ephemerovirus, Novirhabdovirus

Question 2

Lyssavirus

Answer 2

Can cause rabies like disease in animals and humans. Bats are potential reservoirs.

Question 3

Vesiculovirus

Answer 3

Viruses of horses, cattle, swine, and humans. Some have been isolated from fish such as carp and salmonids.

Question 4

N protein

Answer 4

makes up the major capsid component, the viral nucleocapsid

Question 5

P protein

Answer 5

is a cofactor of the viral polymerase

Question 6

M protein

Answer 6

an inner protein that facilitates virion budding (binds N and G proteins)

Question 7

L protein

Answer 7

Is an RNA dependent RNA polymerase (transcription and replication of viral RNA)

Question 8

Virions are sensitive to

Answer 8

UV radiation from the sun, detergent based disinfectants and iodine containing solutions are effective disinfectants. Oxidizing agents, acids, aldehydes.

Question 9

Rabies Virus

Answer 9

Infects all mammals. Skunks, raccoon, foxes, and wolves are reservoirs in North America. Most commonly vampire bats and silver-haired bats

Question 10

Urban Rabies Cycle

Answer 10

Dogs are the main reservoir. This cycle predominates in areas of Africa, Asia, and Central and South America.

Question 11

Sylvatic (of wildlife)

Answer 11

Cycle is predominant cycle in the northern hemisphere. It can also present simultaneously with the urban cycle in some parts of the world.

Question 12

Clinical Phases of Rabies - Prodromal Phase

Answer 12

Aggressiveness in tame animals. Daytime activities in nocturnal animals. No fear of humans in wild animals.

Question 13

Clinical Phases of Rabies - Excitative (fury) phase

Answer 13

Severe agitation and aggressiveness. Bites any material. High barking sound.

Question 14

Clinical Phases of Rabies - Paralytic (dumb) phase

Answer 14

Inability to swallow. Excessive salivation. Hydrophobia in dogs. Complete paralysis is followed by death.

Question 15

Pathogenesis and Pathology of Rabies Virus

Answer 15

Virus binds to receptor for acetylcholine at neuromuscular junctions.

Question 16

Diagnosis of Rabies Virus

Answer 16

Tissues from two locations in the brain (the brain stem and cerebellum). Performed only in reference laboratories.

Question 17

Rabies Virus - Laboratory Diagnosis

Answer 17

Immunochemical identification of rabies virus antigen

Question 18

Rabies Virus - Control

Answer 18

Vaccines are available.

Question 19

Vesiculovirus - Vesicular Stomatitis Virus (VSV)

Answer 19

Infects cattle, swine and horses. Causes vesicular stomatitis. REPORTABLE/ ZOONOTIC DISEASE!

Question 20

VSV - Clinical Features

Answer 20

Salivation, fever are first signs in cattle and horses. Lameness is a first sign in swine. Vesicles on tongue, oral mucosa, teats, coronary bands (cattle and swine). In horses tongue lesions are most pronounced.

Question 21

VSV - Pathogenesis

Answer 21

Virus enters the body through mucosal or skin abrasion. Virus replicates in intraepithelium of mucosae and skin.

Question 22

VSV - Epidemiology

Answer 22

Virus is transmitted by biting insects such as sand flies, black flies, house flies, and mosquitoes.

Question 23

VSV - Diagnosis

Answer 23

Clinically indistinguishable from other vesicular diseases of swine and cattle (e.g., foot and mouth disease). Vesicular lesions in horses are only characteristic of VSV infection. Only reference laboratories can do diagnostic testing.

Question 24

VSV - Prevention and Control

Answer 24

Control or flies. Inactivated or attenuated virus vaccines have been tested but not yet available commercially.

Question 25

Novirhabdovirus

Answer 25

Viral hemorrhagic septicemia virus. Infectious hematopoietic necrosis virus.

Question 26

Vesiculovirus

Answer 26

Spring viremia of carp virus. Pathogens of wild and cultured fish.

Question 27

Viral hemorrhagic septicemia virus - Clinical Signs

Answer 27

Darkened body color, exophthalmia, hemorrhage at base of fins. Distention of abdomen due to ascites.

Question 28

Viral hemorrhagic septicemia virus - Diagnosis

Answer 28

There is no commercial vaccine available

Question 29

Bovine ephemeral fever virus

Answer 29

Ephemerovirus. Not reported in north and south america.

Question 30

Bovine ephemeral fever virus - Clinical features

Answer 30

Seaons disease for summer and autumn, Biphasic or polyphasic fever. Immediate drop in milk production. Occasionally nasal and ocular discharges. Cessation of rumination. Constipation and abortion may occur. Infrequent diarrhea, temporary or permanent paresis.

Question 31

Bovine ephemeral fever virus - Diagnosis

Answer 31

Gold standard - virus isolation in mosquito cell culture or suckling mouse brain. RT-PCR. Neutralization test. Immunofluorescence of gel diffusion.

Question 32

Bovine ephemeral fever virus - Prevention

Answer 32

Gives long-lasting immunity. Animals born after the outbreak are susceptible to infection. Inactivated and attenuated virus vaccine is used. A recombinant baculovirus vaccine is available.