Test: Vaccination & Immunisation - Grade 12 MCQ

Louis Pasteur discovered the technique of preparing vaccine from an attenuated pathogen in 1879. This was the first true vaccine consisting of weakened micro-organisms against the disease chicken cholera.

The term vaccine was coined by Edward Jenner. A vaccine is a suspension or extract of weakened pathogens which when injected into a healthy person provides active acquired immunity to the disease.

Edward Jenner prepared his first vaccine of smallpox by using pathogens from cow pustule. He injected fluid from the sore of milkmaid suffering from cowpox into the body of a healthy boy which did not later catch smallpox.

The vaccines produced through genetic engineering are considered safe because they contain antigen only from the coat of pathogen which is almost harmless.

The basic principle of immunisation or vaccination is based on the property of memory of the immune system. When an immunised person is attacked by the pathogen, the existing bodies immediately attack the antigen while the memory T and B cells give rise to a massive crop of lymphocytes and antibodies.

NCERT Topic: Vaccination and immunisation

NCERT Line: "The principle of immunisation or vaccination is based on the property of 'memory' of the immune system."

ATS inoculation soon after injury that brings contact with soiled objects give protection against the possible attack of tetanus. Wounds and cutes or surgical instruments coming in contact with the road dust may cause the entry of spores into the body. Injection of ATS within 24 hours of injury gives passive immunity to the individual.

NCERT Topic: Immunisation and vaccination

NCERT Line: "if a person is infected with some deadly microbes to which quick immune response is required as in tetanus, we need to directly inject the preformed antibodies, or antitoxin (a preparation containing antibodies to the toxin)."

A disease against which vaccination resorts only during epidemics is Cholera. Vaccination against cholera gives immunity for only a few months. It is useful, especially during epidemics. Chlorination or ozone treatment of water, boiled water, disinfected food are measures essential for prevention.

Von Behring was awarded the noble prize for his work on passive immunity. He is also regarded as the Father of Passive immunity.

A single vaccination gives adequate immunity and lasts lifelong is the incorrect statement. It may not give adequate immunity. Therefore, 2-3 booster doses of vaccine are administered later on at specific intervals.

NCERT Topic: Vaccination and immunisation

NCERT Line: "C:\nA single vaccination gives adequate immunity and lasts lifelong"

Explanation:
The correct answer is active immunity. Here is a detailed explanation:
Active immunity refers to the immunity that develops in response to an infection or vaccination. It involves the activation of the body's immune system and the production of specific antibodies to fight off the disease-causing agents. This type of immunity is long-lasting and provides protection against future infections with the same pathogen.
Here are some key points about active immunity:
1. Natural active immunity: This type of immunity occurs when a person gets infected with a pathogen and develops an immune response, resulting in long-term protection against that specific pathogen.
2. Artificial active immunity: This type of immunity is acquired through vaccination. Vaccines contain weakened or inactivated forms of disease-causing agents, which stimulate the immune system to produce a response similar to a natural infection. This response leads to the development of specific antibodies and memory cells, providing immunity against future infections.
3. Memory cells: During active immunity, the immune system produces memory cells that "remember" the specific pathogen. If the person is exposed to the same pathogen again, the memory cells quickly recognize and mount a rapid and effective immune response, preventing the person from getting sick.
4. Duration of active immunity: Active immunity can last for years or even a lifetime, depending on the pathogen and the individual's immune response.
In contrast, passive immunity refers to the temporary immunity that is transferred from one individual to another. This can occur naturally, such as the transfer of antibodies from a mother to her baby during pregnancy or breastfeeding, or artificially, through the administration of antibodies obtained from another person or animal. Passive immunity is short-lived and does not involve the activation of the recipient's immune system.
In summary, active immunity refers to the immunity developed after the body has recovered from a disease or has been vaccinated. It involves the production of specific antibodies and memory cells, providing long-lasting protection against future infections with the same pathogen.

NCERT Topic: Active and passive immunity

NCERT Line: "When a host is exposed to antigens, which may be in the form of living or dead microbes or other proteins, antibodies are produced in the host body. This type of immunity is called active immunity."