Question

Read the following statements (1 - 4) related to vaccination and select the correct statements.

1. Vaccines are modified biological agents.
2. Viral vaccines readily mimic natural infection.
3. Edward Jenner coined the term vaccine.
4. The process of developing immunity is called vaccination.

• A. 1 and 2
• B. 1, 2, and 3
• C. 2 and 4
• D. 1, 2, 3 and 4

Answer 1

The correct option is B 1, 2, and 3

Vaccination refers to the administration of any vaccine. Immunisation is the process by which the body produces antibodies or immune cells (memory B cells and T cells) against pathogens through administration of specific vaccines. Hence statement 4 is incorrect.

Figure : Mechanism of action of vaccine

Biological agents include living organisms and their products. For example, bacteria, viruses, fungi, and the toxins they produce. Vaccines are indeed modified biological agents introduced in the body to develop acquired immunity against a particular disease. So statement 1 is correct.

Vaccines contains an inactivated (weakened or killed) form of the disease causing microorganisms, its surface proteins or toxins (toxoids) produced by them.

When the vaccine is introduced in the body, it mimics (behaves the same way), the pathogen. The immune system recognizes the threat and destroys the pathogen or its parts present in the vaccine. This will help the immune system to remember and initiate an appropriate response in a subsequent encounter with the same pathogen in future. So statement 2 is correct.

Vaccination helped in the eradication of many diseases including smallpox. Vaccine for smallpox was the first successful vaccine developed, and was introduced by Edward Jenner in 1796. He coined the term vaccine. So statement 3 is correct.

The term 'vaccine' is derived from the Latin word 'vacca', which means 'from cows' because Jenner prepared the vaccine for smallpox from cowpox.

Figure : Edward Jenner