Active immunity is the straight response of the body towards pathogens. These pathogens are infectious microorganisms. They are also foreign substances that develop following an infection or vaccination.
It might take longer for the response to take place. At times, it might be a long life. It is for this reason; active immunity is referred to as natural or acquired. Active immunity activates the immune system to produce antibodies against a certain infective factor.
Passive immunity is the transfer of active humoral immunity of ready-made antibodies. It is provided when someone is given an antibody to a disease rather than producing them through the immune system. Passive immunity occurs naturally. For instance, the fetus receives antibodies from the mother through the placenta.
Active vs Passive Immunity
The difference between Active and passive immunity is that active immunity is produced actively by the immune system of the host. Passive immunity, on the other hand, is produced by the immune system of the host passively.
Comparison Table Between Active and Passive Immunity (in Tabular Form)
|Parameter of Comparison||Active Immunity||Passive Immunity|
|Durability||They offer long-lived protection.||They offer short-term protection|
|Reactivation||They are restored by an event of infection or revaccination||For renewed protection, they need periodic re-administration.|
|Booster effect||Coming doses with antigen results in booster effect||Due to immune elimination succeeding doses are less effective|
|Suitability||It’s not fit for safeguarding immune-deficient or immune-compromised people||In cases of severe combined immunodeficiency, immune-deficient, or immune-compromised passive immunity is suitable|
|Use||Active immunity is useful for prophylaxis of diseases||Passive immunity is effective as a post-exposure treatment|
|Protection effectiveness||Active immunity provides effective protection||It provides less effective protection and may not be complete|
|Response time||The protective response time takes some time to form. This is because of the presence of delay time.||Protection is instant because there is no lag period.|
What is Active Immunity?
Active immunity is whereby an immune system produces antibodies against a specific agent. There are two ways to acquire active immunity. It can be acquired by receiving a vaccination or contracting an infectious disease.
Active immunity is everlasting. Any individual with active immunity is safe from diseases the entire life. But it can be reactivated by the occurring of the infection or by revaccination. This immunity does not cost much to prepare and apply.
The major drawback is that active immunity depends on the individual immune response. That is why it is not effective to protect immuno-deficient or immuno-compromised people.
What is Passive Immunity?
Passive immunity refers to the immunity produced by one person and passed to another antibody of a different person. This immunity does not stay forever. It disappears after a few weeks or months.
Passive immunity is short-lived because the recipient needs instant protection from the host. Besides, the recipient is not able to form antibodies fast enough alone.
An example of passive immunity is that of a newborn baby who receives passive immunity from the mother through the placenta. Passive immunity helps to slow down or prevent the flow of disease. It is also suitable for people with immune system deficiencies. They are, however, costly to produce.
Main Differences Between Active and Passive Immunity
- Definition – Active immunity is where an individual immune system is activated to produce antibodies and lymphocytes. Passive immunity is where antibodies and lymphocytes are produced by another individual immune system. They are then transferred to another person’s immune system.
- Immune System Involvement – With active immunity, the immune system of the person is involved in the process. The immune system of the recipient is passive. It does not participate positively in the process.
- Antigen exposure – Active immunity needs to be exposed to the pathogen. If not, to the antigen of a virus or bacteria. Passive immunity doesn’t require to be exposed to epidemic agents or antigen.
- Artificial acquirement – Active immunity is given out by human beings through vaccination. Passive immunity is given out by the administration of preformed antibodies.
- Natural acquirement – Active immunity come about without special intervention when one is exposed to a pathogen or antigen. Passive immunity comes about naturally when breast-feeding an infant absorbs antibodies through the mother’s milk. Still, they arise when a fetus ingests antibodies from the other through the placenta.
- Type of Immunity – active immunity involves humoral and cell-mediated immunity. Passive immunity is given out by ready-made antibodies.
- Memory cell formation – Passive immunity is not formed. Active immunity produces a long-lasting memory cell.
- Components – active immunity is formed up of T cells, B cells, and antigen-presenting cells. T cells comprise cytotoxic T cells, helper T cells, memory T cells, and suppressor T cells. B cells are made up of memory B cells and plasma cells. Antigen-representing cells are made up of B cells, dendritic cells, and macrophages. Passive immunity got no immune cells involved because the antibody is performed.
- Secondary response – With active immunity, the first exposure leads to the first response. If there is another exposure to the same pathogen a fast and stronger secondary reaction is set. There is the absence of a secondary response in passive immunity.
Both active and passive are types of adaptive immunity. They also deal with antibodies and can either be acquired naturally or artificially.
Active immunity is created by the antibodies by the individual’s body. Passive immunity, on the other hand, is mediated by antibodies produced outside. Passive can be used to generate a rapid immune response. Antibodies were among the primary tools used to treat specific infectious diseases. At the moment, antibodies play a vital role in fighting infectious diseases.
The origin of the antibodies used in each type of immunity is the main difference between active and passive immunity.