Poxviridae

Question 1

What are the 2 subfamilies of family Poxviridae?

Answer 1

Chordopoxvirinae

Entopoxvirinae

Question 2

Which genus of Poxviridae appears

ovoid in shape with long threadlike surface tubules arranged in a criss-cross pattern like a “ball of yarn”?

Answer 2

Genus Parapoxvirus

Question 3

Poxviruses have ________ symmetry

with a dumbell shaped core and 2 lateral bodies

Answer 3

complex symmetry

Question 4

What are the 2 important viral particles found in Poxviruses?

Answer 4

**EEV **(Extracellular Enveloped Virus)

and

**IMV **(Intracellular Mature Virus)

Question 5

T/F:

Both EEV and IMV poxvirus particles are infectious

Answer 5

TRUE

Question 6

Which viral particle of poxviruses is released by budding and has 2 membranes?

Answer 6

EEV

Question 7

Which viral particle of poxviruses is released by cell lysis and has 1 membrane?

Answer 7

IMV

Question 8

Describe the genome of Poxviruses

Answer 8

Linear DSDNA

Question 9

The smallest genus of Poxviridae is

Answer 9

Parapoxvirus

Question 10

The largest genus of *Poxviridae *is

Answer 10

Entomopoxvirus

Question 11

What is special about how viruses in Poxviridae replicate?

Answer 11

Poxviridae is a DNA virus

that can replicate

in the cytoplasm

^{because they have evolved to encode enzymes for transcription and replication}

Question 12

Antigenic characteristics of Poxviridae include

NP nucleoprotein and genetic recombination within genus.

ONLY one genus of Poxviridae has antigenic hemagglutinin (HA)

which is it?

Answer 12

Orthopoxviruses

have HA

Question 13

How does the **stability **of Poxviridae differ from other enveloped viruses?

Answer 13

Unlike other enveloped viruses, Poxviridae is

extremely stable in the environment

and can remain infectious for months, as well as survive for years in dried scabs

Question 14

Which Poxvridae genus can be transmitted via the respiratory route?

Answer 14

Capripoxvirus (sheeppox)

Question 15

*Poxviridae *is highly ___________, meaning it causes cutaneous skin lesions

Answer 15

epitheliotropic

Question 16

Most genuses of family *Poxviridae *are host-specific

EXCEPT for genus ____________

Answer 16

Orthopoxvirus

infects many species

Question 17

Describe the summary of skin lesions typically seen in Poxviruses

Answer 17

Macule → Papule → Vesicle → Pustule → Scab or Ulcer → Scar

Question 18

What is the difference between a **macule **and a papule?

Answer 18

A macule is a flat red lesion of local inflammation,

A papule is a raised red lesion indicative of invasion of neighboring tissues

Question 19

Which comes first, a vesicle or a pustule?

Answer 19

vesicle

Question 20

If this bursts, an ulcer is formed

Answer 20

If a pustule ruptures, an ulcer is formed

otherwise, the pustule remains intact and a scab forms

Question 21

Cowpox, Monkeypox, Smallpox, Camelpox, Ectromelia, Horsepox, Rabbitpox,

*Uasin Gishu Virus, Ectromelia virus, *and Vaccinia virus

are all virus species belonging to this genus

Answer 21

Genus Orthopoxvirus

Question 22

T/F:

Cowpox, a species of Orthopoxvirus is COMMON in cows

Answer 22

FALSE!

*Cowpox *is UNCOMMON in cows!

Question 23

________ is endemic in Europe and Asia only, while

_________ is confined mostly to remote villages in central and west Africa

Hint: Both are species of Orthopoxvirus

Answer 23

Cowpox is endemic to **Europe **and Asia

and

Monkeypox is found in remote villages of Africa

Question 24

Rodents serve as a reservoir host in this virus endemic to Europe and Asia only

Answer 24

Cowpox

Question 25

*Cowpox *mostly infects \_\_\_\_\_\_, Humans, and Zoo animals

Answer 25

_Cats_

Question 26

A newly partruitioned cow had been seen hanging out with an orange farm cat. After about 5 days, the cow started acting *mildly febrile*, and developed *lesions on her teats*. Her suckling calf then developed *lesions in its mouth*. Later, it was noticed that this cow had a *decreased milk yield*. What are your **5 DDx** for these symptoms?

Answer 26

* Cowpox* * Pseudocowpox* * Bovine Herpesvirus* * Vesicular stomatitis* * Udder Impetigo *(bacterial dermatitis)

Question 27

A newly partruitioned cow had been seen hanging out with an orange farm cat. After about 5 days, the cow started acting mildly febrile, and developed lesions on her teats. Her suckling calf then developed lesions in its mouth. Later, it was noticed that this cow had a decreased milk yield. **The farmer calls you back and you find out new information.** **The cow is from eastern europe, and histology shows the _HA hemagglutinin antigen_**. What is your definitive diagnosis?

Answer 27

Only *Orthopoxviruses* have the HA antigen, so this cow is suffering from ## Footnote *Cowpox*

Question 28

Your outdoor cat came in one day with a *single lesion* on his head. After 8 days, *several other lesions* appeared and about 2 days after that, the lesions turned into *discrete, circular and ulcerated papules *about 1 cm diameter. After a while, you noticed he had a stuffy nose, or *mild coryza* and some *conjunctivitis*. **What is your diagnosis**? Can you get this virus from your cat? What symptoms should you look for in yourself?

Answer 28

*Cowpox (Orthopoxvirus)* infection via a rodent or arthropod bite from being outside YES, this virus is **zoonotic** and symptoms you may experience are * macropapular lesions on your hands and face* * enlarged and painful local lymph nodes* * fever, vomiting, and sore throat*

Question 29

What virus should you be worried about if treating *monkeys in remote villages in central and west Africa**?*

Answer 29

*Monkeypox (Orthopoxvirus)*

Question 30

Genus *Parapoxvirus* includes what 3 species of viruses?

Answer 30

* Pseudocowpox* * Contagious Ecthyma (ORF virus)* * Bovine Papular Stomatitis Virus*

Question 31

A newly partruitioned cow had been seen hanging out with an orange farm cat. After about 5 days, the cow started acting mildly febrile, and developed lesions on her teats. Her suckling calf then developed lesions in its mouth. Later, it was noticed that this cow had a decreased milk yield. **The farmer tells you that he is from Canada and is seeing "horse-shoe shaped ring lesions" on his cow where the scabs have dropped off. Histology has shown an ovoid shaped virus with a criss-cross pattern on its surface, much like a ball of yarn.** What is your diagnosis?

Answer 31

*Pseudocowpox* species of virus of genus *Parapoxvirus*

Question 32

T/F: The term "Milker's Nodules" refers to human infection by *Cowpox, *a species of genus *Orthopoxvirus*

Answer 32

FALSE!! "Milker's Nodules" refers to *Pseudocowpox*, a species of genus *Parapoxvirus*

Question 33

* Contagious Ecthyma* is also known as * Scabby mouth, Contagious pustular dematitis, and sore mouth*. But what is it **most commonly known as**?

Answer 33

**ORF!** **(parapoxvirus)**

Question 34

A shepherd with a flock of new sheep has noticed that *all* of the baby lambs in his flock have these lesions in their mouths. Out of all the dams, only a few have started showing lesions in the *commissures of their mouths*, at the mucocutaneous junction and a few look like they have lesions on their teats. The shepherd is concerned because this virus seems to be spreading *extremely rapidly.* ## Footnote **What is your diagnosis? What may have caused this virus?**

Answer 34

*Contagious Ecthyma *or **ORF** Because it is a new flock, the shepherd probably used instruments to **dock and ear-tagging pliers** that were *contaminated.* A scab from the environment could have also caused it.

Question 35

A shepherd with a flock of new sheep has noticed that all of the baby lambs in his flock have these lesions in their mouths. Out of all the dams, only a few have started showing lesions in the commissures of their mouths, at the mucocutaneous junction and a few look like they have lesions on their teats. The shepherd is concerned because this virus seems to be spreading extremely rapidly. **The shepherd is concerned about his friend's flock in the neighboring town and asked if you would vaccinate his flock as well.** **What will you tell this shepherd?**

Answer 35

That **NO, you will NOT vaccinate his friend's flock **because you are not supposed to use in farms or flocks that do not already have problems with **ORF/ *Contagious Ecthyma***

Question 36

A shepherd with a flock of new sheep has noticed that all of the baby lambs in his flock have these lesions in their mouths. Out of all the dams, only a few have started showing lesions in the commissures of their mouths, at the mucocutaneous junction and a few look like they have lesions on their teats. The shepherd is concerned because this virus seems to be spreading extremely rapidly. **How will you confirm with histology that this is ORF or *Contagious Ecthyma****?*

Answer 36

Because ORF/ *Contagious Ecthyma* is a parapoxvirus, the virus will look like **a ball of yarn**.

Question 37

A shepherd with a flock of new sheep has noticed that all of the baby lambs in his flock have these lesions in their mouths. Out of all the dams, only a few have started showing lesions in the commissures of their mouths, at the mucocutaneous junction and a few look like they have lesions on their teats. The shepherd is concerned because this virus seems to be spreading extremely rapidly. ## Footnote **Should the shepherd be worried about contracting this from his sheep?**

Answer 37

It is **ORF/ *Contagious Ecthyma*** so **YES**, he should be worried and treated.

Question 38

What are the 3 species of viruses classified as Genus *Capripoxvirus**?*

Answer 38

* Sheeppox* * Goatpox* * Lumpy Skin Disease of Cattle*

Question 39

How do you tell the difference between *Sheeppox *and *Goatpox* using serology?

Answer 39

TRICK! You can't

Question 40

*Sheep and Goatpox* are **endemic to which regions**?

Answer 40

**Africa** **Asia** **Europe**

Question 41

A farmer in Africa with a mixed flock of non-native merino sheep and african local breed of sheep, has noticed that his favorite sheep Buttercup is exhibiting signs of *depression, salivation, watery eyes, and runny nose*. Her eyes seem swollen. The local vet is out of town so it will take you 4 days to get there. After 4 days, almost 75% of the merino flock is exhbiting the same symptoms, and almost all the baby lambs have died. But amazingly, the local sheep seem unaffected. Buttercup is now showing lesions on her phaynx, larynx, and vagina, and these lesions are leaving a star-shaped scar. What is your diagnosis?

Answer 41

**Malignant form of *sheeppox* (*Capripoxvirus)***

Question 42

A farmer in Africa with a mixed flock of non-native merino sheep and african local breed of sheep, has noticed that his favorite sheep Buttercup is exhibiting signs of* depression, salivation, watery eyes, and runny nose*. Her eyes seem swollen. The local vet is out of town so it will take you 4 days to get there. After 4 days, almost 75% of the merino flock is exhbiting the same symptoms, and almost all the baby lambs have died. But amazingly, the local sheep seem unaffected. Buttercup is now showing lesions on her phaynx, larynx, and vagina, and these lesions are leaving a star-shaped scar. **What is the first thing you should do upon figuring out that this is *Sheeppox*?**

Answer 42

**REPORT IT IMMEDIATELY!**

Question 43

There is a flat, hemorrhagic form of _________ in some European Goats with a high case fatality rate

Answer 43

_Goatpox_

Question 44

A herd of cattle in Iraq has been experiencing *fever, mutiple nodular lesions on their skin and mucous membranes, and have enlarged lymph nodes.* This virus is **enzootic to subsaharan africa and the middle east**. What virus is causing these symptoms, and what is the protocol for treatment?

Answer 44

*Lumpy Skin Disease (Capripoxvirus)* Unfortunately, you must slaughter all infected and in-contact cattle :(

Question 45

The owner of a piggery has noticed lesions on the abdomen and inner thighs of some of his younger pigs. A few pigs look a little greasy with exudative lesions. One mother pig had piglets recently and all of her piglets now have lesions covering their entire body, including some lesions in the upper respiratory tract! What is causing this virus, and what is the virus called?

Answer 45

*Swinepox (Genus Suipoxvirus)* caused by **pig louse Hematopinus suis**

Question 46

This virus can occur in 3 different forms: Dry (cutaneous) form Diptheritic (wet) form Ocular form

Answer 46

***Fowlpox (Genus Avipoxvirus)***

Question 47

This is the first virus ever grown in embryonated eggs

Answer 47

Fowlpox (Avipoxvirus)

Question 48

Which form of *Avipoxvirus/Fowlpox* is the most common?

Answer 48

**Cutaneous (DRY) form**

Question 49

Which form of *Avipoxvirus/ Fowlpox* has the **worst prognosis**? How do these animals die?

Answer 49

**Diptheritic (WET) form** **Chickens die from asphyxiation when the lesions coalesce and form a necrotic pseudomembrane**

Question 50

How is *Avipoxvirus/Fowlpox* controlled?

Answer 50

With vaccination with a **modified live fowlpox** and by control the most common vector of transmission, **mosquitoes**

Question 51

Which unclassified sheep virus has 2 clinical forms: ## Footnote **Lip and Leg Ulceration Form** **Veneral Form- Balanoposthitis**

Answer 51

***Ulcerative Dermatosis of Sheep***

Question 52

Most poxviruses have this slightly basophilic characteristic intracytoplasmic inclusion body

Answer 52

**Type B Guarnieri Inclusion Bodies**

Question 53

What type of intracytoplasmic, strongly eosinophilic inclusion bodies will you see in the histology of *Cowpox* and *Ectromelia virus*?

Answer 53

**Type A ATI** **Inclusion Bodies**

Question 54

Avipoxviruses are the ONLY poxviruses with this characteristic intracytoplasmic inclusion body

Answer 54

**Bollinger and Borrel Bodies**

Question 55

You can diagnose most poxviruses using inoculation into an embryonated egg (CAM) technique. Which poxvirus will not grow in the chicken embryo?

Answer 55

**Parapoxviruses** **(Pseudocowpox, Contagious Ecthyma/ORF, and Bovine Papular Stomatitis)**