In immunology a vaccine is a biological preparation that provides acquired immunity to a particular infectious or malignant disease ; based on the principle of passive secondary immune response.

British physician Edward Jenner is considered as the founder of vaccinology. In the year of 1976 Dr. Jenner inoculated a thirteen year old boy with vaccinia virus the infective agent responsible for cow pox disease and thus he successfully demonstrated that immunity against smallpox can be achieved by administration of the antigen (vaccinia virus) responsible for cowpox into the bloodstream of an individual. On the basis of Dr. Jenner’s research findings the first smallpox vaccine was developed in the year of 1978. As a long term strategy for fighting against the smallpox disease the preventive vaccine for small pox is administrated to the masses throughout the globe during 18th and 19th century and that ultimately leads to a small pox free globe, as declared by W.H.O in 1979.

For the first time when an individual has faced an infection caused by a specific pathogen initially the primary immune response is developed that yields the production of antibodies. During this period simultaneously B – lymphocytes of cell mediated acquired immunity yields memory B cell that has capability for quick and well effective neutralisation of the pathogen/antigen concerned and thus contributes to the active primary immune response.

However In comparison to primary immune response secondary immune response is an extremely specific, rapid and efficient immune response developed by the acquired immunity system. Technically passive secondary immune response is an artificial modification of the active secondary immune response to replace the natural infection (that may be fatal) by an artificial infection (non fatal). Hence antibody specific antigen, pathogenic population ( within the threshold limit) or heat killed population is transferred from the cultured colony to a healthy person with no history of previous infection by the pathogen concerned.

Edibles vaccine varies from the traditional vaccine with a fine line of difference. i.e. the route of administration and it’s biochemical nature. While traditional vaccines are mostly administrated into a subject through sub cutaneous injection on the other hand an edible vaccine (mostly fruit containing the antigen) is taken by a healthy individual via oral route that is taken up by M cells of intestine and finally passed out to the various cells of the immune system so that B- lymphocytes can yield memory cells that remains dormant until the individual is not infected by the same pathogen/antigen and secondly in addition to the specific antigen ; traditional vaccines may contain the neutralised pathogen where as edible vaccines are inclusively specific to the antigen.