Question

Which of the following is an example of a live vaccine?
A. TAB vaccine
B. Pertussis vaccine
C. Meningococcal vaccine
D. BCG vaccine

Answer 1

Hint: A vaccine is biological preparations which contain dead, weakened or live attenuated form of microbe which resembles the disease causing microorganism. It stimulates the body’s immune system which recognises it and destroys it and also keeps it in memory for future.

Complete Answer:
The vaccines are used as an effective way of preventing the disease. The first vaccine was developed by Edward Jenner for the cowpox. The vaccines are composed of a dead organism or a live and weakened form of the diseases causing microbes. It brings about immune responses.
 Few examples of vaccine are-
(I) TAB vaccine- TAB vaccine is used for preventing typhoid and paratyphoid. It is a killed bacterial vaccine which is given by mouth.
(II) Pertussis vaccine- It protects against pertussis. It is available in two forms- cellular and acellular vaccines.
(III) Meningococcal vaccine- It protects against the infection of Neisseria meningitidis. It consists of a polysaccharide capsule.
(IV) BCG vaccine- It is a live and attenuated vaccine which protects against tuberculosis.

Thus the correct answer is (D).

Additional Information: WHO has organised several drives for the eradication of diseases like polio. The oral vaccines are given to the children.

Note: A live vaccine is made from a live pathogen which is weakened to make it non-virulent. They replicate in the individual and bring out an immune response with no disease. Vaccines for smallpox, yellow fever and influenza are live and attenuated.