Differences between Active Immunity and Passive Immunity
The major differences are:
|S.N.||Characteristics||Active Immunity||Passive Immunity|
|1.||Definition||The protective immunity in which the individual’s own immune system is stimulated to produce antibodies and lymphocytes.||The immunity in which a person receives antibodies or lymphocytes that have been produced by another individual’s immune system.|
|2.||Exposure to Antigen||Requires exposure to a pathogen or to the antigen of a pathogen.||Does not require exposure to an infectious agent or its antigen.|
|3.||Immune system involvement||The immune system of the individual is actively involved in the process.||The immune system of the individual is not actively involved but rather passive.|
|4.||Natural acquirement||Arise naturally when an individual is exposed to an antigen or pathogen (clinical infection).||Arise naturally when a fetus receives antibodies from the mother across the placenta or when a breast-feeding infant ingests antibodies in the mother’s milk.|
|5.||Artificial acquirement||Conferred artificially by means of vaccines.||Conferred artificially by administration of preformed antibodies.|
|6.||Immunity type||Involves both humoral and cell mediated immunity.||The immunity is conferred only by readymade antibodies.|
|7.||Components||T cells (cytotoxic T cells, helper T cells, memory T cells, and suppressor T cells), B cells (memory B cells and plasma cells), and antigen-presenting cells (B cells, dendritic cells, and macrophages).||No immune cells are involved as antibody is preformed.|
|8.||Antibody production||Involves antibody production which is induced by infection or immunogen.||No antibody is produced, but directly transferred.|
|9.||Memory cell formation||Active immunity results in the formation of long-lasting memory cells.||Memory immune cells are not formed.|
|10.||Secondary response||The first exposure leads to primary response and incase of a subsequent exposure to same pathogen later, a much faster and stronger secondary response is established.||Absence of a secondary response.|
|11.||Durability||The protection offered is long-lived.||The protection is only transient.|
|12.||Response time||The protective response takes time to establish as a lag period is present.||No lag period hence the protection is instant.|
|13.||Reactivation||Reactivated by recurrence of infection or by revaccination.||Frequent re-administration needed for renewed protection.|
|14.||Booster effect||Subsequent doses with antigens cause booster effect.||Subsequent doses are less effective due to immune elimination.|
|15.||Suitability||Active immunity is not suitable for protection of immuno-compromised or immuno-deficient individuals.||Passive immunity is useful in cases of immuno-compromised, immuno-deficient or severe combined immunodeficiency.|
|16.||Use||Very effective for prophylaxis of diseases.||Artificial passive immunity is effective as a post-exposure remedy.|
|17.||Effectiveness of Protection||Provides effective protection.||Protection rendered is less effective and may not be complete.|
|18.||Adverse effect||It can be implicated in autoimmune diseases and allergies, but generally does not have side effects.||A condition called serum sickness can result from exposure to antisera.|
|19.||Examples||Natural – Producing antibodies in response to exposure to a pathogenic infection such as measles or cold.
Artificial – Producing antibodies in response to the controlled exposure to an attenuated pathogen (i.e. vaccination).
|Natural – Receiving antibodies from another organism (e.g. to the foetus via the colostrum or a newborn via breast milk).
Artificial – Receiving manufactured antibodies via external delivery (e.g blood transfusions of monoclonal antibodies).
- The College of Physicians of Philadelphia (2018, January 10). Passive Immunization. Retrieved from https://www.historyofvaccines.org/content/articles/passive-immunization
- Encyclopaedia Britannica (2017, November 22). Immunization. Retrieved from https://www.britannica.com/science/immunization.
- Lydyard, P.M., Whelan,A.,& Fanger,M.W. (2005).Immunology (2 ed.).London: BIOS Scientific Publishers.