VBD- viruses

Question 1

What is a vector-borne disease?

Answer 1

Any infectious disease caused by pathogens transmitted by arthropods or other invertebrate intermediaries.

Question 2

Why have vector-borne diseases become increasingly important in recent years?

Answer 2

Due to the geographic expansion of pathogens and arthropod populations, and the emergence of novel agents.

Question 3

What significant event occurred regarding West Nile virus in 1999?

Answer 3

It was introduced into New York and spread across North America within 4 years.

Question 4

Approximately how many people were infected by West Nile virus in the decade following its introduction?

Answer 4

1.8 million people.

Question 5

What are some other mosquito-borne viruses that have emerged in North America?

Answer 5

• Dengue outbreaks (1999)
• Chikungunya (2013, 2014)
• Zika pandemic (2014, 2015)

Question 6

What is the primary method of transmission for vector-borne pathogens?

Answer 6

Blood feeding by an infected insect or acarine parasite.

Question 7

How long does it typically take for Borrelia burgdorferi to be transmitted during tick feeding?

Answer 7

24 to 48 hours.

Question 8

True or False: Vaccines are available to protect people from infections like West Nile virus and Lyme disease in the United States.

Answer 8

False.

Question 9

What is the mainstay of protecting health from vector-borne diseases?

Answer 9

Controlling vector populations.

Question 10

What role do warmer ambient temperatures play in the transmission of flaviviruses?

Answer 10

They are needed for efficient transmission.

Question 11

What is the primary vector for arboviruses?

Answer 11

Mosquitoes.

Question 12

What historical discovery was made regarding Babesia bigemina?

Answer 12

It was the first confirmation of arthropod transmission of an infectious agent.

Question 13

Which diseases are associated with the Togaviridae family?

Answer 13

• Eastern equine encephalitis
• Western equine encephalitis
• Venezuelan equine encephalitis

Question 14

What are the reservoir hosts for West Nile virus?

Answer 14

Birds.

Question 15

Fill in the blank: The transmission rate of a pathogen is defined as the number of new infections that occur per unit _______.

Answer 15

time.

Question 16

What factors influence the transmission rate of vector-borne diseases?

Answer 16

• Characteristics of the vector
• Characteristics of the reservoir host
• Characteristics of the pathogen

Question 17

What is the role of reservoir hosts in vector-borne disease transmission?

Answer 17

They must be susceptible to infection and share a common niche with the competent vector.

Question 18

What is a key factor that can affect the efficiency of transmission of infectious agents?

Answer 18

Ecologic interactions between vectors and reservoir hosts.

Question 19

What are arboviruses?

Answer 19

Viral pathogens transmitted by arthropod biologic vectors.

Question 20

List one example of a viral disease transmitted by arthropods.

Answer 20

West Nile virus.

Question 21

True or False: Secondary vectors cannot transmit the same pathogens as primary vectors.

Answer 21

False.

Question 22

What is the significance of the extrinsic incubation period in vector-borne diseases?

Answer 22

It influences how rapidly the vector can transmit the organism after acquisition.

Question 23

Name one disease caused by the Bunyaviridae family.

Answer 23

Rift Valley fever.

Question 24

What is the primary method through which vectors can transmit multiple pathogens?

Answer 24

Co-infection.

Question 25

What is the family of the Fowlpox virus?

Answer 25

Poxviridae

Question 26

Which virus is associated with Myxomatosis?

Answer 26

Myxoma virus

Question 27

What type of virus is the Equine infectious anemia virus?

Answer 27

Lentivirus

Question 28

What are the vectors for Equine infectious anemia?

Answer 28

Stomoxys spp., Chrysops spp.

Question 29

What are the main viruses in the Togaviridae family referred to as?

Answer 29

Alphaviruses

Question 30

Name a virus that has emerged in new geographic locations, causing significant epidemics.

Answer 30

Chikungunya virus

Question 31

What is the estimated human case range during the Chikungunya outbreak on the Indian continent?

Answer 31

1 to 6 million

Question 32

Which viruses are commonly referred to as EEE, WEE, and VEE?

Answer 32

Eastern, Western, and Venezuelan equine encephalitis virus

Question 33

What is the mortality rate of EEE virus infection in horses?

Answer 33

Approaching 90%

Question 34

What is the main reservoir host for the Japanese encephalitis virus?

Answer 34

Pigs

Question 35

True or False: Domestic animals are involved in transmission cycles of St. Louis encephalitis.

Answer 35

False

Question 36

Fill in the blank: West Nile virus was introduced to North America in _______.

Answer 36

1999

Question 37

What type of fever is associated with the Rift Valley fever virus?

Answer 37

Zoonotic

Question 38

Which viruses cause encephalitis in people and are transmitted by mosquitoes?

Answer 38

* West Nile * Japanese * St. Louis * Murray Valley

Question 39

What is the primary vector for Bluetongue virus in North America?

Answer 39

Culicoides variipennis

Question 40

What is the main disease caused by the African horse sickness virus?

Answer 40

Severe, often fatal disease of horses

Question 41

Which tick is a vector for Colorado tick fever virus?

Answer 41

Dermacentor andersoni

Question 42

What is the family of the African swine fever virus?

Answer 42

Asfarviridae

Question 43

Fill in the blank: Infection of pigs with ASF virus results in high fever, _______.

Answer 43

anorexia

Question 44

Which virus is transmitted to ruminants by biting midges?

Answer 44

Bluetongue virus

Question 45

What is a key characteristic of the disease caused by Powassan encephalitis?

Answer 45

Neurologic disease

Question 46

What are the two types of VEE virus?

Answer 46

* Endemic * Epizootic

Question 47

What is the transmission method of the Crimean-Congo hemorrhagic fever virus?

Answer 47

Tick feeding

Question 48

True or False: Dogs commonly show disease symptoms due to Powassan virus.

Answer 48

False

Question 49

What is a common outcome for humans infected with Rift Valley fever virus?

Answer 49

High morbidity but low mortality

Question 50

Name two diseases associated with tick-borne viruses.

Answer 50

* Louping ill * TBE

Question 51

What is the primary reservoir for the Usutu virus?

Answer 51

Birds

Question 52

What type of vector is primarily responsible for the transmission of EHD virus?

Answer 52

Biting midges

Question 53

What virus is classified with other ASF-like viruses as an Asfarviridae?

Answer 53

African Swine Fever (ASF) virus ## Footnote ASF is transmissible between pigs and can be maintained in soft ticks.

Question 54

How is the ASF virus transmitted to pigs?

Answer 54

Transmissible through Ornithodoros spp. soft ticks and mechanically by blood-feeding flies like Stomoxys calcitrans ## Footnote ASF can be maintained in ticks for years and transmitted when ticks feed.

Question 55

What are the symptoms of ASF infection in pigs?

Answer 55

High fever, anorexia, hemorrhage, rapid death ## Footnote Mortality can approach 100% with the most virulent strains.

Question 56

What is the current status of treatment and vaccines for ASF?

Answer 56

Not currently available ## Footnote ASF poses significant challenges for swine health management.

Question 57

What is mechanical transmission of viruses by arthropods?

Answer 57

Transfer of viruses facilitated by arthropod vectors without the need for biological replication ## Footnote Iatrogenic transmission via needle inoculation is also a factor.

Question 58

Which virus is mechanically transmitted between rabbits by blood-feeding arthropods?

Answer 58

Myxoma virus ## Footnote Causes severe infections in European rabbits, leading to control efforts in Australia and Europe.

Question 59

What is the outcome of myxoma virus infection in native rabbits versus European rabbits?

Answer 59

Native rabbits develop mild fibromas; European rabbits develop severe, usually fatal infections ## Footnote European rabbit populations can develop resistance over time.

Question 60

What virus is transmitted mechanically by horseflies and deerflies among horses?

Answer 60

Equine infectious anemia virus ## Footnote Infection can lead to high fever and death or chronic disease in horses.

Question 61

What is the Coggins test used for?

Answer 61

To identify carriers of equine infectious anemia virus ## Footnote Segregation of infected horses helps prevent transmission.

Question 62

What disease is caused by avian pox viruses in birds?

Answer 62

Fowlpox ## Footnote Can be transmitted mechanically by mosquitoes or directly between birds.

Question 63

What are the symptoms of fowlpox infection in birds?

Answer 63

Hyperplastic cutaneous lesions, decreased growth and production ## Footnote Severe lesions can lead to mortality due to predation or starvation.

Question 64

What is the treatment status for fowlpox once lesions have developed?

Answer 64

No treatment available ## Footnote Vaccines are available to prevent disease in poultry.