Immunization and Immunity

Posted on : September 2, 2021 by Clinic One on Immunity System


Immunity has been defined as a complex biological system having the capability to identify and permit whatever belongs to self, and identifying and reject whatever is foreign to self.

A body is said to have gained immunity to a disease when it formulates antibodies in an individual system to fight the infection.

Proteins produced by the body that neutralizes or destroys toxins or disease-causing organisms are explained to be antibodies; antibodies have been said to be disease-specific, meaning antibody of a specific disease protects an individual against that particular disease, but will not have any effect upon other disease infection. 

Immunity is said to be of two types-

  • Active immunity
  • Passive immunity

Active immunity 

When an individual is exposed to a disease organism and his/her body alerts the immune system to produce antibodies against the infection, this particular process has been referred to as active immunity.

The exposure to the disease organism can be natural infection triggering natural immunity or can be vaccine-induced immunity, in which case a weakened or killed form of the disease organism is introduced to a body through vaccination to trigger the immune response.

In both cases, it is said that when an immune individual is introduced to the disease-causing organism in the future, that individual’s immune system will recognize the disease and soon after that will produce antibodies that are required to fight the disease. 

Active immunity is said to be long-lasting and at times even lifelong. 

Passive immunity

When an individual is given antibodies to disease in place of the body producing them by its immune system this process is called passive immunity.

The placenta is said to provide a newborn infant with passive immunity from its mother.

Blood products such as immune globulin are said to provide an individual with passive immunity, which is said to be given when an individual requires immediate protection from a peculiar disease.

The ability to provide immediate protection is considered to be a major advantage of passive immunity, as active immunity is said to take several weeks to develop.

Even though passive immunity is considered to be quicker to provide protection it is said to last only for a small period (a few weeks or months) unlike active immunity that is said to be long-lasting.      


Immunization has been defined as a process in which an individual is protected against disease through vaccination.

It has been said that immunity gained through immunization resembles the kind of immunity a person might have developed if infected by a disease, without being infected by the disease.

When an individual is immunized their body is said to react in a way it would have if he/she was infected with the disease; an individual’s body is said to assume an infection and reacts to it by producing antibodies to fight off the infection.

These antibodies are said to stay in an individual’s system for a long term and memorize how to fight the infection in case infected by the particular disease-causing organism naturally in the future.

It has been said that individuals are most likely to be fully protected against the disease after being immunized, but in rare cases even after being immunized an individual still can be susceptible to the disease because of receiving only a portion of protection through a vaccine, this has been said to occur among individuals with medical conditions that affect one’s immune system.

Even though these individuals might get infected by the disease it has been noted that they are less likely to suffer serious complications and might have milder effects of the disease if infected. 

Life cycle of immunization programs 

Center for disease control and prevention has said that the life cycle immunization programs ideally have a beginning, middle, and end in some cases.

They have described a typical life cycle of an immunization program in the following way- 

  • When a vaccine hasn’t been discovered for a disease the number of people getting infinite by it is typically high and individuals worry about the disease and complications. 
  • Later when immunization programs are held
  • the number of people getting vaccinated is said to high 
  • There is said be very few  reaction to the vaccine which are said to be comparatively milder than what complications the disease might have caused in individuals
  • As the number of individuals getting vaccinated increases as a correlation the number of individuals being infected by the disease decreases, and personals experiencing side effects are usually very low and might even fall back. 
  • At this particular stage It is said a significant amount of the population might not be infected by the disease, and might not be concerned about the disease and it’s complications but might start worrying about the side effects of the vaccine. The question of whether the vaccine is safe or if it is necessary to get vaccinated might arise among individuals and they might stop getting immunized. 
  • It is said that is a significant number of individuals stop getting immunized the number of people getting infected by the disease too might rise because of which there would be a disease. 
  • Which leads people to resort to immunization through vaccine again, as they see the complications the disease causes  is far more severe than vaccine reactions. The number of people getting vaccinations increase to avoid the disease and it’s complications and the number of people getting infected by the disease comes down. 
  • It is said that is if sufficient number of individuals get immunized the disease would altogether disappear. ( Smallpox is an example of such happening) 
  • When the disease disappears the immunization program can be stopped and the number of vaccination and vaccine related reactions ends .       

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One thought on "Get a Flu Vaccine to minimize COVID19 effect | Flattening the curve"

  1. M. mathema says:

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