What should you know about for how long is chickenpox contagious?

The virus spreads through respiratory droplets and contact with fluid from skin blisters. A person may be infectious before the rash is recognised, then remain able to spread chickenpox while new blisters are appearing and older ones have not crusted.

Once all lesions are dry and crusted, contagiousness generally ends, but a rash diagnosis can be uncertain. Shingles is a related condition caused by reactivation of the same virus; it does not spread as chickenpox in exactly the same way.

Stay home and avoid close contact with pregnant people, newborn babies, people with weakened immunity and anyone who has not had chickenpox or vaccination. Do not share towels, clothing or bedding, and wash hands after touching the rash. Call a clinic before attending so staff can advise on safe arrangements.

A GP consultation can confirm the diagnosis and discuss antiviral treatment when clinically appropriate. Oral antihistamine treatment may be considered for itch, but use medicines only as advised for the person's age and health.

Seek urgent medical advice for breathing difficulty, confusion, severe headache, repeated vomiting, dehydration, a very unwell appearance or rapidly worsening skin redness. Contact a clinician promptly if the person is pregnant, very young, immunocompromised or has a high fever or painful infected-looking blisters.

Does this rash fit chickenpox or another blistering illness? When can the person safely return to school or work? Is antiviral treatment appropriate, and which itch treatment is suitable? Should close contacts discuss chickenpox vaccination or urgent preventive advice?