VIRO-LEC poxviridae

Question 1

• Large, complex, enveloped DNA viruses
• Largest viruses

Answer 1

Poxviridae

Question 2

What is the shape of virions of Poxviridae?

Answer 2

Brick-shaped or oval

Question 3

What type of genome is present in Poxviridae?

Answer 3

Large, linear, double-stranded genomes

Question 4

Where does Poxviridae replicate?

Answer 4

Host cell cytoplasm, which is unusual for DNA viruses

Question 5

They are known to create intracytoplasmic inclusion bodies called _________ bodies in infected cells

Answer 5

Guarnieri

Question 6

Poxviridae is divided into 2 subfamilies and these are ______ and ______.

Follow up question: What type of host does these 2 subfamilies of Poxviridae infect and wht are their genera?

Answer 6

1. Chordopoxvirinae, which infects vertebrates; includes several genera
   - Orthopoxvirus
   - Parapoxvirus
   - Avipoxvirus
   - Capripoxvirus
   - Leporipoxvirus
   - Suipoxvirus
   - Molluscipoxvirus
   - Yatapoxvirus
2. Entomopoxvirinae, which infects insects; includes several genera
   - Alphaentomopoxvirus- Infects beetles (Coleoptera)
   - Betaentomopoxvirus- Infects butterflies and moths (Lepidoptera) and grasshoppers and locusts (Orthoptera)
   - Gammaentomopoxvirus- Infectious mosquitoes,flies,and midges(Diptera)

Question 7

Poxvirus-infected cells produce ____ and _____

Answer 7

Mature virions (MV) & Enveloped virions (EV)

Question 8

What is the characteristics of Poxviridae virions?

Answer 8

Virions consist of a dumbbell-shaped core and two lateral bodies surrounded by one (MVs) or two (EVs) lipid membranes

Question 9

____ are stable and mediate transmission between hosts, while ___ are more fragile facilitate spread within the host.

Answer 9

MVs & EVs

Question 10

TRUE OR FALSE

Poxviruse have a complex structure, lacking an isometric nucleocapsid with icosahedral or helical symmetry.

Answer 10

TRUE

Question 11

What are the 3 types of Transcription process (which occurs in temporal cascade) in Poxviridae?

Answer 11

Early Gene Transcription, Intermediate Gene Transcription, Late Gene Transcription

Question 12

It is initiated by viral transcriptase and other factors carried in the virion core.

Answer 12

Early Gene Transcription

Question 13

encode transcrip factors for late genes

Answer 13

Intermediate Gene

Question 14

___ encode virion proteins and early transcription factors packaged in virions.

Answer 14

Late Gene

Question 15

• linear double-stranded DNA virus and the causative agent of smallpox
• highly contagious and deadly disease
• eradicated in 1980 making it the first human pathogen eliminated through vaccination

Answer 15

Variola virus

Question 16

What is the prevention and treatment of Variola virus?

Answer 16

• Smallpox vaccine (Vaccinia virus) was key to eradication.
• Routine vaccination stopped post-eradication but is available for bioterrorism preparedness.
• Antivirals (Tecovirimat, Cidofovir) now available for potential outbreaks

IMMUNITY: Infections confers lifelong immunity

Question 17

• causes monkeypox
• disease similar to smallpox but with lower mortality
• first identified in 1958 in monkeys but is primarily maintained in rodent reservoirs

Answer 17

Monkeypox virus

Question 18

What is is the route of infection of Monkeypox virus?

Answer 18

Animal-to-human, Human-to-human, Sexual transmission

Question 19

Monkeypox prevention and treatment:

Answer 19

• Vaccination: Jynneos (Modified Vaccinia Ankara, MVA): FDA-approved, safer for immunocompromised individuals.
• Supportive care: Fluids, pain management, secondary infection prevention.
• Antivirals: Tecovirimat (Tpoxx), FDAapproved for monkeypox; Brincidofovir, DIAGNOSIS: Cidofovir: Used in severe cases

Question 20

is zoonotic and closely related to Vaccinia virus and primarily affects buffaloes in India, Pakistan, Egypt, and Indonesia

Answer 20

Buffalopox virus

Question 21

• Direct contact with infected buffaloes spreads the virus to farmers, milkers, and veterinarians.
• Causes localized pustular lesions, fever, and mastitis in buffaloes.
• Human infections cause self-limiting skin lesions but can be severe in immunocompromised individuals

Answer 21

Buffalopox virus

Question 22

• First identified in Brazil, associated with outbreaks in cattle and humans
• Zoonotic transmission from cattle to humans, likely through direct contact.
• Causes vesiculopustular skin lesions in both cattle and infected humans

Answer 22

Aracatuba virus

Question 23

• known as contagious ecthyma or sore mouth
• a zoonotic virus, meaning it can be transmitted between animals and humans
• infects sheep and goats, causing a contagious skin disease

Answer 23

Orf Virus

Question 24

What are the clinical features of orf virus?

Answer 24

1. Small red spot (macule) or bump (Papule) appears.
2. Develop into a taret-like appearance with RED HALO SURROUNDING a NECROTIC CENTER
3. Lesions filled with fluid forming blister (vesicle) -> pus-filled lesion (pustule)
4. Pustule ruptures and forms a crust or scab
5. Lesion gradually hels, scab falls off leaving no scar.