Question

What is a vaccine?

Answer 1

A vaccine is a biological preparation that provides active acquired immunity to a particular disease.

Explanation:

A vaccine is made from weakened or killed form of microbe, it's toxin or one of its surface proteins. This stimulates the body's immune system to recognise the injected agent as a threat, destroy it and thus recognise and destroy any of these microorganisms that it later encounters.

Vaccination began in the 18th century with the work of Edward Jenner and the small pox vaccine. Vaccination is the most effective method of preventing infectious diseases. They may be prophylactic or therapeutic.