Hi,
You have asked a very good question.
Usually a person who has got chicken pox is infective and can transmit infection to a normal healthy individuals from 2 days before onset of rash to 5 days after rash till scab is formed.
Once a person got exposed it may manifest 10-21 days after exposure.
Hope that answers your query.
Answered2017-09-30 15:59:05
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