Chickenpox

Question 1

What pathogen causes chickenpox, how does it spread, and how long is the incubation?

Answer 1

1. varicella zoster virus
2. respiratory droplets
3. 11 to 21 days

Question 2

How long do children remain infective before rash development in chickenpox?

Answer 2

4 days

Question 3

What are the clinical features of the incubation period of chickenpox?

Answer 3

Asymptomatic

Question 4

What are the clinical features of the prodromal period of chickenpox and how long does it last?

Answer 4

Fever, malaise, pharyngitis, anorexia, 24-hours.

Question 5

What are the clinical features of the exanthem period of chickenpox and how long does it last?

Answer 5

Generalized pruritic vesicular rash which starts on the head or trunk before spreading, rarely on palms or soles of feet, several days.

Question 6

What is the progression of the lesions in chickenpox?

Answer 6

Macular than papular than vesicular

Question 7

What are the clinical features of the evolving phase chicken pox and how long does it last?

Answer 7

Lesions crust over and fall off by 2 weeks, lasts less than 4 days.

Question 8

How is chickenpox diagnosed?

Answer 8

1. clinical diagnosis

2. dew drops on a rose petal, lesions appear in crops.

Question 9

What is the management for chickenpox?

Answer 9

1. Keep cool, trim nails, calamine lotion to soothe, exclusion from school for at least 5 days after onset of rash.
2. anti-VZV Igs and acyclovir if immunocompromised or on steroids

Question 10

What are the complications of chickenpox and what medication should you avoid using?

Answer 10

1. necrotising fasciitis if vesicles become black

2. avoid NSAIDs as they increase the risk of superimposed bacterial infection, commonly group A strep

Question 11

What is the pathophysiology of shingles?

Answer 11

Varicella-zoster virus lives in dorsal root ganglion, virus reactivates later in life and causes shingles in dermatomal pattern.