hi Dr, my son(1 year 3 months 13 days old) has got his chicken pox vaccination on Sunday(11th April) however it seems that he has got some bumps of chicken pox on his hands and legs now. is it that the vaccine is not effective for treating chicken pox? what kind of foods / medication shall be avoided for the child? also is it contagious? what should be done to avoid getting infection to others?. please advise asap.