Active Immunity
Active immunity is acquired by the production of antibodies (humoral) against antigens, presented by pathogens. This can be categorised as either natural or acquired. The mode of natural methods was by direct contact with the pathogen and enduring the infection, leading to the antibody production by the immune system. This mode of immunity usually takes few days or weeks for initial response however lasts a lifelong. Along with antibody production, a memory of a portion of the antigen was also stored as memory B-cells both in bone marrow and also in circulating blood; thus during subsequent exposure to the same infection, these memory B-cells begin to replicate and produce antibodies much efficiently, e.g. wild hepatitis A virus infection (Baxter, 2007; Portnoy, 2004). There are however, some exceptions e.g. malaria. Individuals develop only a partial immunity against Plasmodium falciparum even after multiple exposure to malaria. Individuals with this type of partial immunity may still be infected but do not display severe disease conditions. It is also important to note that level of risk of infection directly affects the risk of disease severity in malaria-infected individuals (Doolan, Dobano, & Baird, 2009). …show more content…
Vaccines contains antigen that induce immune system in individuals to produce antibodies and immunologic memory cells, similar to that of natural mode of active immunity except for disease symptoms e.g. two doses of hepatitis A vaccination, since it was legalised in 1980s, is administrated to individuals after 1 year of age (Baxter, 2007). There are other factors such as antibodies transferred from mother, age of an individual, nutrition intake, dose of antigen exposure, presence of adjuvant e.g. aluminium-containing materials, etc., that have direct effect on immune responses (Dhaar & Robbani, 2008; S. A. Plotkin, 2008,
Active immunity is acquired by the production of antibodies (humoral) against antigens, presented by pathogens. This can be categorised as either natural or acquired. The mode of natural methods was by direct contact with the pathogen and enduring the infection, leading to the antibody production by the immune system. This mode of immunity usually takes few days or weeks for initial response however lasts a lifelong. Along with antibody production, a memory of a portion of the antigen was also stored as memory B-cells both in bone marrow and also in circulating blood; thus during subsequent exposure to the same infection, these memory B-cells begin to replicate and produce antibodies much efficiently, e.g. wild hepatitis A virus infection (Baxter, 2007; Portnoy, 2004). There are however, some exceptions e.g. malaria. Individuals develop only a partial immunity against Plasmodium falciparum even after multiple exposure to malaria. Individuals with this type of partial immunity may still be infected but do not display severe disease conditions. It is also important to note that level of risk of infection directly affects the risk of disease severity in malaria-infected individuals (Doolan, Dobano, & Baird, 2009). …show more content…
Vaccines contains antigen that induce immune system in individuals to produce antibodies and immunologic memory cells, similar to that of natural mode of active immunity except for disease symptoms e.g. two doses of hepatitis A vaccination, since it was legalised in 1980s, is administrated to individuals after 1 year of age (Baxter, 2007). There are other factors such as antibodies transferred from mother, age of an individual, nutrition intake, dose of antigen exposure, presence of adjuvant e.g. aluminium-containing materials, etc., that have direct effect on immune responses (Dhaar & Robbani, 2008; S. A. Plotkin, 2008,