Chicken pox

Chicken pox is a very contagious disease caused by the varicella-zoster virus

Transmission and infectiouness of Chicken pox

Chicken pox is transmitted in the air from person to person and by direct contact.

It takes approximately 14 - 18 days for the symptoms of chicken pox to appear after catching the virus

You are contagious 2 days before the onset of the rash and for one week after.

Infected children must avoid contact with babies, pregnant women, and immuno-compromised people like HIV, those undergoing or following cancer treatment.

Symptoms of Chicken pox

  • A rash presents, characterised by small fluid filled blisters appearing gradually all over the body.
  • The blisters after about a week dry out and form scabs. Once dry they are no longer contagious.
  • The blistery lesions can appear in the mouth, on the scalp... anywhere.
  • A fever and headache accompany the rash and a dry cough and sore throat is common.
  • The rash causes considerable itching. Spots will only scar if they are badly scratched and some spots can become infected.


See your GP if you are unsure about the diagnosis or have concerns about any complications.
  • Keep the skin clean and dry.
  • Use antihistamine medication to prevent the child from scratching, as to avoid secondary infection and scaring.
  • Paracetamol helps control the fever and helps with feeling unwell.

Recognise serious complications of chicken pox

  • High temperature, stomach pains, vomiting, drowsiness, secondary infections of the spots or a rash which looks like bruises or small bleeds into the skin and generally becoming more and more unwell.
  • Pneumonia, encephalitis can appear in rare cases.
  • The risks are greater in newborn babies, pregnant women and immunosuppressed people.
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