Herd immunity provides protection to-: (A) Immunized persons, (B) Non immunized persons, (C) Both, (D) None
Answer is B. Herd immunity describes a type of immunity that occurs when the vaccination of a poion of the population provides protection to unprotected individuals provides an immunological barrier to the spread of disease in human herd elements-(a) occurence of clinical and sub clinical infection in the herd ( b ) immunization of the herd ( c) herd structure (refer pgno:102 park 23 rd edition).