What are the difference between active and passive immunity

Our bodies develop immunity against disease in different ways. When we contract relatively mild illnesses like chickenpox and the measles – typically as children – we usually develop natural, lifelong immunity against them after infection activates our immune systems. Getting vaccinated against more serious diseases like COVID-19 and influenza (the flu) is another way to become actively immune to a disease. It’s uncommon for people to naturally develop long-lasting immunity against diseases like these, so getting vaccinated multiple times against them helps soften the virus’ strength. Passive immunity occurs when a person receives antibodies from someone else. Passive immunity does not require previous exposure to a disease agent – either through infection or vaccination – like active immunity does. Here is a further breakdown of these two forms of immunity.

Table of Contents Show

Combined Active and Passive Immunity
Other forms of Immunity
Local Immunity
Herd Immunity
What is the difference between active and passive immunity and provide an example of each?
What is the difference between active and passive immunity quizlet?

Natural activitE immunity

When we breathe in new air, eat new food or touch unfamiliar things, the natural, active immunity in our bodies usually springs into action. The active immune response can take days or even weeks to develop. Once it does develop, it’s long-lasting – sometimes even lifelong.

Vaccine-induced active immunity

Also known as artificial active immunity, vaccine-induced immunity gives our bodies a controlled way to create an immune response. When a weakened or dead form of a disease organism is injected into our bodies or administered via the mouth or as a nasal spray, that’s vaccine-induced immunity. Examples include:

The COVID-19 vaccine
The flu vaccine

COVID-19 vaccines are the safest way to build immunity against COVID because they cause a strong immune response. Getting the COVID-19 vaccine gives a high level of protection against the disease while providing an added layer of protection for those who have already had it. When we are vaccinated against COVID we typically have a higher initial immune response and a longer immune memory than unvaccinated people who have recovered from COVID-19 and developed a semblance of natural immunity. The flu can be serious among young children, older adults, and people with certain chronic health conditions like asthma, heart disease or diabetes, according to the Centers for Disease Control and Prevention (CDC). That’s why getting vaccinated is a safer choice than risking illness to gain immune protection. A drawback to active immunity is that it doesn’t protect us against mutations of diseases that the body already has antibodies to, so when diseases mutate, they change structure in ways that our immune systems can’t recognize.

Passive Immunity

Passive immunity occurs when a person is given antibodies to a disease rather than producing them through their own immune systems. Passive immunity does not require previous exposure to a disease agent – either through infection or vaccination – like active immunity does. An example of passive immunity is when a baby acquires maternal antibodies transferred through its mother’s breastmilk or placenta. Another example of passive immunity occurs when people are treated with antibody-containing blood products, such as immune globulin. Immune globulin shots are designed to provide temporary, but swift protection against diseases like:

Hepatitis
Rabies
Tetanus

The difference between active and passive immunity

Unlike active immunity, passive immunity provides immediate protection. But that protection is generally short-lived, as the supply of antibodies is not being replenished like they would be in someone whose own immune system was generating them. If you’re wondering why vaccine-induced immunity is considered a form of active immunity, while immune globulin shots are passive, it is because immune globulin is a substance made up of antibodies that are naturally made by the body to provide protection from certain diseases. A vaccine is made up of actual viruses or bacteria that stimulate the body to make more antibodies. So, in the case of vaccines, your body still doing the heavy lifting. Your immune system treats the viruses and bacteria like any other exposure and begins actively fighting it. We rely on active and passive immunity to contribute to a well-equipped and strong immune system. Photo credit: Getty Images Keep reading:

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.

Active Immunity vs Passive Immunity Table Form
Combined Active and Passive Immunity
Other forms of Immunity
- Local Immunity
- Herd Immunity
References

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 breastfeeding 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 the 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 a primary response and in case of subsequent exposure to the 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 the recurrence of infection or by revaccination.	Frequent re-administration is needed for renewed protection.
14.	Booster effect	Subsequent doses with antigens cause booster effects.	Subsequent doses are less effective due to immune elimination.
15.	Suitability	Active immunity is not suitable for the 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 fetus via the colostrum or a newborn via breast milk). Artificial – Receiving manufactured antibodies via external delivery (e.g blood transfusions of monoclonal antibodies).

Combined Active and Passive Immunity

Combined 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 Immunity

Local Immunity

The immunity at a particular site, generally at the site of invasion and multiplication of a pathogen, is referred to as local immunity.
Local immunity is conferred by secretory IgA antibodies in various body secretions.
These antibodies are produced locally by plasma cells present on mucosal surfaces or in secretory glands.
Natural infection or attenuated live viral vaccines are given orally or intranasally induces local immunity at gut mucosa and nasal mucosa, respectively.

Herd Immunity

Herd immunity refers to an overall level of immunity in a community, which means that when enough people in a community have been exposed to a pathogen, then it can not spread easily.
With herd immunity, as more people become immune, the pathogen will have a smaller pool of people to infect and result in fewer outbreaks within the community.
To eradicate an infectious disease sometimes it depends on the development of a high level of herd immunity against the pathogen. An epidemic of disease is likely to occur when herd immunity against that disease is very low indicating the presence of a larger number of susceptible people in the community.
However, not all pathogens spread with the same efficiency, the community levels of immunity necessary to benefit from herd immunity vary.
For example, because measles is one of the most contagious pathogens known, a community requires almost everyone to be immune in order to stop its transmission. But it is much more difficult for an individual to benefit from herd immunity to measles than from most other infectious agents. Therefore, vaccines have made it easier for society to reap the benefits of this type of protection.
Herd Immunity and COVID-19 has been debated upon by researchers stating that it can be achieved through natural infection but will have serious consequences, and therefore, it is not a solution to immunity to COVID-19.

References

http://www.easybiologyclass.com/difference-between-active-immunity-and-passive-immunity-comparison-table/
https://www.thoughtco.com/active-immunity-and-passive-immunity-4134137
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.

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 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.