Hi, welocme and Thanks for writing in.
I will tell you few thing about disease first.

Causetive organism and features: Chickenpox is a highly contagious but non-threatening disease caused by primary infection with varicella zoster virus.t usually starts with vesicular skin rash mainly on the body and head rather than at the periphery , which mostly heal without scarring. Unique feature if it is vesicles are seen at various stages of healing.

Mode of Infection: it is a airborne disease spread easily through coughing or sneezing of ill individuals or through direct contact with secretions from the rash. A person with chickenpox is infectious one to two days before the rash appears. They remain contagious until 6 to 7 days when all lesions gets crusted over.

Now regarding adult onset disease: symptoms are
•Fever (temperature), aches and headache .
•Rash.
•Cough, sore throat, and feeling sick are common.
Imoprtant point is that symptoms are more aggresive in adults than children.It will not occur unless and until you have contact with a active case. Hopefully you vaccinated against chickenpox in childhood. Then there is less chance to get infected.

Hope i have answered your query. If you any specific query regarding same please let me know.

Regards.

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