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Vaccine is a substance that induces immunity without causing disease. Vaccines can be made with live attenuated microorganisms, killed microorganisms or the product of the microorganisms. The product may be natural or synthetic.The peptide vaccines are considered as an alternative to classical vaccines that try to address the issue of possible side effects.The peptide vaccines are based on in vitro synthesised peptides of 20-30 amino acids,known to be highly immunogenic and to trigger the desired immune response.These peptide vaccines can be designed with self or non self -antigen to properly balance the immune responses,which is not possible for conventional vaccines.The series of limitations and failures in peptide vaccine in clinical trials include :limitations of single peptide epitopes as vaccine candidates;an immune invasion;failure to elicit controlled and prolonged immune response;lack of efficacy and inappropriate design. Better way to prove its efficacy is to produce the vaccine for a regional strain of the microbe.