Chicken Pox.

 

Definition:

Chicken pox predominantly occurs in childhood, and is an acute disease which is usually self limiting. It is highly contagious and is spread by personal contact or droplet spread. Chicken pox will cause a rash to appear and for the child to feel unwell.

 

 

Causes:

Chicken pox is caused by the varicella-zoster virus. During the infection, the body produces antibodies which provide lifelong protection, making it unlikely that the patient will suffer from another bout of chicken pox. However, the virus can be reactivated later to cause herpes zoster (shingles) in adults- this reactivation may be triggered by stress.

 

 

Presentation:

Prodromal symptoms may appear a day or so before the rash, including nausea, myalgia, loss of

appetite and general malaise.

 

The rash begins as red itchy spots, which will turn into fluid filled blisters. It is likely to appear on the

trunk, face, scalp and proximal limbs, but can appear anywhere on the body. These blisters will crust

over within 1-4 days, and drop off within 1-2 weeks. Until the blisters crust over, the patient is still

contagious and can pass on the virus.

 

 

Differential Diagnosis:

Exclude insect bites and scabies (scabies is characterised by small red blotches and silver coloured

lines on the skin, and are usually found in the folds of skin, or on the wrists or elbows)- these can be

confused with Chicken Pox.

 

If the patient is pregnant, less than 4 weeks old or immunocomprimised, they should be referred.

 

 

Treatment:

Paracetamol can be used to help with mylagia and as an antipyretic (for example Calpol Sugar-free Infant Suspension). Children can have a dose up to FOUR times daily (or every 4-6 hours), not more frequently than every FOUR hours.

4-6 years: 10ml

2-4 years: 7.5ml

6-24 months: 5ml

3-6 months: 2.5ml

 

Calamine & Glycerin Cream or Aqueous Calamine Cream may be recommended to help soothe the itching.

 

For a child over one year chlorphenamine can be given to help with the itching (e.g. Piriton Syrup).

6-12 years: 10ml 4-6 hourly

2-6 years: 2.5ml 4-6 hourly

1-2 years: 2.5ml twice daily

 

 

Self Help Advice:

Stay hydrated, ice lollies are a good way to ensure a child keeps fluid levels up and will soothe any spots in the

mouth.

 

Do not scratch- it can cause infection.

 

Wear cool, loose fitting clothing to help to reduce the fever.

 

Avoid contact with pregnant women, immunocompromised people and infants under 4 weeks of age.

 

The child can go back to school when the last spot has crusted over.

 

 

Sample Question:

Which of the following is true about chicken pox (herpes zoster)?

 

a)The vesicles produced by this disease contain large quantities of the virus 

b) Women who are pregnant should avoid contact with people infected with this 

disease because of risk of congenital abnormalities 

c) Vaccination against this disease is routinely given during the first year of life 

in the form of a combined vaccine with diptheria, tetanus, Haemophilus 

influenza type b and polio

d) The disease causes characteristic white spots surrounded by a red ring 

(koplik spots) on the inner cheek and gum

 

Answers to all sample questions can be found by following the link under the Test Yourself tab.