Social & Preventive Medicine General 2b0b950d Spread of chicken pox is maximum ? A After formation of scab B Just before and after onset of rash C One week before onset of rash D During convelescence High-Yield Explanation Ans. is 'b' i.e., Just before and after onset of rash Communicable period (period of maximum infectivity) in chicken pox is 2 days before to 5 days after onset of rash.