Poxvirus

Question 1

Characteristics

Size, complexity, genome

Answer 1

Largest and most complex virus known, double-stranded DNA virus

Question 2

Is it easy to grow in the lab?

Answer 2

Yes

Question 3

What hosts do they have?

Answer 3

Have their specific animal hosts (humans, monkeys, rodents, cows, sheeps)

Question 4

What are infections mostly characterised by?

Answer 4

Rash

Question 5

What antibodies does it induce?

Answer 5

Both specific and cross-reacting antibodies

Question 6

What is human poxvirus called and which virus?

Answer 6

Small pox
Variola virus

Question 7

How is smallpox transmitted by?

Answer 7

Respiratory route from lesions in respiratory tract

Question 8

Where does smallpox virus distribute to?

Answer 8

Internal organs during 12 day incubation

Question 9

What is the clinical presentation of smallpox?

Answer 9

Rash appears suddenly - papular, vesicular, pustular, leaving pink scars

Question 10

How is poxvirus vaccines prepared?

Answer 10

From vesicular lesions produced in skin of calves and sheep, or it can be grown in chick embryos

Question 11

What is the risk of poxvirus vaccines?

Answer 11

Mild reactions to fatal encephalitis

Question 12

What does Molluscum contagiosum lead to? Where does it present in children and adults?

Answer 12

Small papule that grows into discrete, waxy, smooth, dome-shaped, pearly or flesh-coloured nodule
Children: trunk and proximal extremities
Adults: trunk, pubic areas and thighs

Infection is usually benign and painless

Question 13

How is Molluscum contagiosum spread?

Who does it tend to occur in?

Answer 13

• Direct contact (may be skin-to-skin after sexual intercourse)
• Fomites (towels, swimming pools)

Tends to occur in children

Question 14

How is Molluscum contagiosum diagnosed?

Answer 14

• Clinical appearance
• Confirmed by PCR (semi-solid caseous material can be expresed from lesions)

Question 15

How is Molluscum contagiosum treated?

Answer 15

Spontaenous recovery!
Treatment is for comestic reasons

Question 16

How is Monkeypox transmitted?

Answer 16

• Zoonotic (rodents)
• Close contact
• Sexual route
• Vertical (mother to child)

Question 17

What is the clinical presentation of Monkeypox?

Answer 17

• Lesions (firm, rubbery, well-circumscribed, deep-seated, often with umbilication)
• Evolution of lesions from macular, papular, vesicular, pustular, scabbing, desquamation
• Rash often in genital, anorectal areas, mouth (not always across many body sites, confined to only a single or few lesions, not always on palms and soles)