Principles of Vaccine Use Route of Administration Microbes differ in their routes of infection, patterns of transmission, and predispositions for certain age groups. The route of vaccine administration (oral, intranasal, intradermal, transdermal, subcutaneous, or intramuscular) takes these factors into account in order to maximize protection and minimize adverse events. Vaccine development is more a pragmatic undertaking than an exact science, guided only in part by immunologic principles and shaped largely by the results of clinical trials. While vaccines can theoretically be given by any route, each vaccine has unique characteristics adapted to a particular route and, in practice, must be given. | Chapter 116. Immunization Principles and Vaccine Use Part 4 Principles of Vaccine Use Route of Administration Microbes differ in their routes of infection patterns of transmission and predispositions for certain age groups. The route of vaccine administration oral intranasal intradermal transdermal subcutaneous or intramuscular takes these factors into account in order to maximize protection and minimize adverse events. Vaccine development is more a pragmatic undertaking than an exact science guided only in part by immunologic principles and shaped largely by the results of clinical trials. While vaccines can theoretically be given by any route each vaccine has unique characteristics adapted to a particular route and in practice must be given by the licensed route for which optimal immunogenicity and safety have been documented. For example vaccines containing adjuvants are designed for injection into the muscle mass. Mucosal administration of vaccines designed for parenteral administration may not induce good systemic responses because such vaccines do not induce mucosal secretory IgA. Administration of hepatitis B vaccine into the gluteal rather than the deltoid muscle may fail to induce an adequate immune response while SC rather than IM administration of DTaP vaccine increases the risk of adverse reactions. Injectable biologicals should be administered at sites where the likelihood of local neural vascular or tissue injury is minimized. Age Because age influences the response to vaccines schedules for immunization are based on age-dependent responses determined empirically in clinical trials. The presence of high levels of maternal antibody and or the immaturity of the immune system in the early months of life impairs the initial immune response to some vaccines . measles and pneumococcal polysaccharide vaccines but not to others . hepatitis B vaccine . In the elderly vaccine responses may be diminished because of the natural waning of the immune system .
