What is the function of a vaccine?

Vaccines are specifically designed to stimulate an immune response in the body, leading to the development of immunity against certain pathogens. When a vaccine is administered, it introduces a harmless component or a weakened/killed version of a pathogen (such as proteins or inactivated viruses) into the immune system. This exposure prompts the immune system to recognize the pathogen as foreign and produces antibodies along with memory cells.

The memory cells remain in the body and enable the immune system to recognize and combat the real pathogen more effectively if encountered in the future. The goal is to prepare the immune system in advance, establishing immunity and reducing the risk of serious illness that could result from actual infection. This preventive approach is crucial in controlling and eradicating infectious diseases and is a cornerstone of public health.

Other options do not accurately reflect the primary role of vaccines. They do not cure existing infections or treat infections directly, and although they can complement antibiotic therapy in some cases, enhancing the effectiveness of antibiotics is not their primary purpose.