Dr. Wan New

Question 1

Which of the following reoviruses are important in vet med (CHOOSE ALL OF THEM; still list all of them please)

Answer 1

-Orthoreovirus
-Orbivirus
-Rotavirus
-Coltivirus
-Aquareovirus
-Cypovirus
-Fijivirus
-Phytoreovirus
-Oryzavirus
-Seadornavirus
-Idnorevirus
-Mycoreovirus
The first three are the most important for veterinary medicine

Question 2

Know the vector for blue tongue

Answer 2

Culicoides spp-Biting midges, (no see ums)

Question 3

Know about orthoreovirus infectivity (what does it get into –> a lot)

Answer 3

• Mammalian- many species
• Avian- chickens, turkeys, geese
• (ubiquitous)

Question 4

Know about avian reovirus infection in chickens and turkeys (what does it cause)

Answer 4

Arthritis,nephrosis, enteritis, chronic resp dz, myocarditis

Question 5

Know which type of reoviridae are involved in seasonal infections (in other words know when culicoides midges hatch)

Answer 5

Summer and early fall

Question 6

Genome for reovirus

Answer 6

•All are segmented, linear, double-stranded RNA (except birnaviruses)
•10-12 segments
o ortho & orbi- 10, rota- 11, colti- 12
•Not enveloped
o capsid shell with three layers- outer layer, core layer, inner layer

Question 7

Rotavirus- seven major groups (A-G, based on VP6) which ones get in swine?

Answer 7

C and E get in swine

Question 8

Know the Susceptibility of rotavirus to disinfectants and low pH

Answer 8

•Resistant to many common disinfectants and stable at low pH
(vs. orbivirus Bluetongue, which is susceptible)

Question 9

Know about different serotypes of blue tongue

Answer 9

•There are 25 Worldwide, but only 5 recognized in the United States. Many can be asymptomatic and each serotype has variable virulence.

Question 10

Know how to control blue tongue disease

Answer 10

•Vx but must match local serotype, Use larvicides and environmental control of Midges

Question 11

His favorite viruses:

Answer 11

Orthomyxo viruses –> flu

Question 12

What is majorly responsible for new emergences of flu viruses

Answer 12

•The ability of influenza virus to undergo recombination with other strains while in the pig or human

Question 13

“Which of the following events at the cleavage site of the HA gene is responsible for the emergence of High Pathogenic Avian Influenza?” aka how do they evolve/ get formed

Answer 13

•Mutation at the cleavage site. Point mutation (drift) recombination insertion( shift)

Question 14

Relative pathogenicity of the avian influenza viruses in regard to hemagglutinin gene types

Answer 14

•Influenza A viruses are divided into subtypes based on antigenic difference among neuraminidase (N) and hemagglutinin (H)
•Of the 16 H subtypes, only H5 and H7 viruses of certain lineages caused high pathogenic avian influenza → H5N1 is of particular concern because it mutates rapidly and has potential to acquire genes from viruses infecting other species. It also can be shed orally or in feces of birds for 10 days that have survived infection
HA: 1-18 subtypes
•NA: 1-11 subtypes
•18 x 11= 198 HA-NA combinations
•H5 and H7 are pathogenic (THis is in bold)

Question 15

H3N8 canine influenza and where did it come from

Answer 15

•From the horse tracks in Florida and got into dogs and blew up

Question 16

In 2015, which of the following subtype A influenza in chickens and turkeys happened in western united states

Answer 16

H5N2

Question 17

Know about the genome organization of influenza A viruses (it’s the same as B, C, etc)

Answer 17

SS RNA Neg sense

Question 18

Which species serves as a mixing vessel for producing pandemic influenza strains (a reason we do not place chicken and pig farms near one another)

Answer 18

Swine

Question 19

What is a reservoir for influenza A viruses

Answer 19

Wild Birds

Question 20

Arboviral (Arbovirus group A) transmission cycles (there is a picture) –> know about the these

a. EEE
b. WEE
c. VEE

Answer 20

Look at a picture in the study guide
a. North America: Endemic - Bird → Culiseta melanura (mosquito) → Promiscuous feeding mosquitoes → Epidemic - Horses and humans
South America: same as North America but can start with Birds & Rodents

b. Endemic - Bird → Culex tarsalis (mosquito) → Promiscuous feeding mosquitoes or Rabbits (then to Ochlerotatus melanimon) → Epidemic - Horses and humans
c. Endemic - Rodents → Culex spp. Mosquito → Selection through E2 T213R mutation in VEEV ID & IE → VEEV subtypes IAB/IC in mosquitoes → horse → mosquito → humans → mosquitoes

Question 21

Know the genus species vector of WEE virus

Answer 21

Culex tarsalis mosquito

Question 22

Know the subtypes of VEE that are the most virulent and epidemic

Answer 22

IAB and IC

Question 23

Know about the alpha viruses and their vectors (cannot distinguish them from one another clinically)

Answer 23

STUDY CHART FROM STUDY GUIDE

• EEEV = Culiseta melanura
• WEEV = Culex tarsalis
• VEEV= multiples mosquitoes → culex, psorophora, aedes

Question 24

Know where the high viremias are

Answer 24

High in passerine birds starlings and wading birds

Low viremia: humans and horses, because they’re dead end hosts

Question 25

Know clinical features of disease by all these viruses (its all the same)

Answer 25

Encephalitis and febrile disease