Immunity can be defined as the ability of a multicellular organism’s body to protect itself from foreign agents and infectious agents, by being able to destroy them to prevent further body infections. Immunity to infectious microorganisms can be achieved by active or passive immunization. In each case, immunity can be acquired either by natural processes
(usually by transfer from mother to fetus or by the previous infection by the organism) or by artificial means such as injection of antibodies or vaccines. Immunity allows the body to fight off infections. And therefore, immunity is composed of two major lines of defense namely: Innate immunity and adaptive immunity. Innate Immunity is the first line of defense in the human body. It is a natural (born with) or a genetic immune defense mechanism. Innate immunity can be either external defense or internal defense. External defense works in protecting the body from exposure to pathogens and it includes skin, tears, and stomach acid. While internal defense otherwise known as the second line of defense includes fever and inflammation, and the mechanisms of phagocytes. Adaptive immunity, also known as acquired immunity, is the third line of defense, which is activated by innate immunity. This type of immunity and the immune responses elicited are acquired by experience only, which means that the immune response is induced by the host’s response to a foreign antigen (pathogen) or by the transfer of antibodies or lymphocytes that are specific to the pathogen. It involves the defense by immune cells and other activated agents such as cytokines. This type of immunity protects the body against specific pathogens. Adaptive immunity can be classified into active immunity and passive immunity. Image Source: BioNinja.
Combined Active and Passive ImmunityCombined passive-active immunity is carried out by giving both preformed antibodies (antiserum) and a vaccine to provide immediate protection and long-term protection, respectively, against a disease. This approach is followed for the prevention of certain infectious conditions, namely, tetanus, rabies, and hepatitis B. Another scenario is, that a person bitten by a rabid animal might receive rabies antibodies (passive immunization to create an immediate response) and rabies vaccine (active immunity to elicit a long-lasting response to this slowly reproducing virus). Other forms of ImmunityLocal Immunity
Herd Immunity
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What are the difference between active and passive immunity?A prominent difference between active and passive immunity is that active immunity is developed due to the production of antibodies in one's own body, while passive immunity is developed by antibodies that are produced outside and then introduced into the body.
What is the difference between active and passive immunity and provide an example of each?Active immunity occurs when our own immune system is responsible for protecting us from a pathogen. Passive immunity occurs when we are protected from a pathogen by immunity gained from someone else.
What is the difference between active immunity and passive immunity quizlet?What is the key difference between active immunity and passive immunity? In active immunity, a body produces its own antibodies; in passive immunity, a person receives pre-made antibodies.
What is an example of passive immunity?For example, passive immunity occurs when a baby receives a mother's antibodies through the placenta or breast milk. It can also occur when a person receives an injection of antibodies to protect against the effects of a toxin such as snake venom.
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