1.1. Chickenpox is a contagious childhood disease. It is caused by the varicella-zoster virus (VZV) and is characterised by the development of an itchy rash as seen in Figure 1.

Figure 1

Children are advised to avoid scratching the area as much as possible to prevent breaking the skin and forming lesions. This is important as lesions in the skin can lead to the development of secondary skin infections.

(i) Explain how lesions in the skin could lead to the development of secondary skin infections in children.

(3)

Cellulitis is an example of a secondary infection of the skin which results in swelling, redness and pain of the tissues in the deeper layers of skin. It can be treated by the use of antibiotics.

(ii) Explain why antibiotics can be used to treat cellulitis caused as a result of chickenpox, but would not be effective in treating the varicella itself.

(2)

1.2. Chickenpox is a childhood illness which usually individuals would experience just once in a lifetime.

Explain why this is.