Vaccines stimulate the immune system to recognize and recall specific invaders, such as viruses or bacteria, without actually causing the disease. This process prepares the immune system to respond more effectively if the individual is exposed to the actual virus in the future.

Here’s an outline of how vaccines function:

Introduction of Antigen: Vaccines contain either weakened or inactivated pathogens, specific pathogen proteins, or genetic material (such as RNA or DNA) that codes for these proteins. These components are referred to as antigens.

Activation of the Immune System: When a vaccine is delivered, the immune system recognizes the antigens as foreign intruders. This identification generates an immunological response.

Immune Response: The immune system initiates a response to remove the antigens. This reaction includes the development of antibodies, which are proteins that precisely target and neutralize antigens. In addition, specific immune cells, such as T cells, are stimulated to assist eliminate pathogen-infected cells.

Memory Formation: After the pathogen has been eliminated from the body, the immune system preserves memory cells (memory B cells and memory T cells) that “remember” the infection. If the person is exposed to the pathogen again, these memory cells can produce a rapid and robust immune response, avoiding or reducing the severity of the infection.

Now, discussing the main distinctions between mRNA vaccines and conventional vaccines:

mRNA vaccines, such as the Pfizer-BioNTech and Moderna COVID-19 vaccines, include genetic material in the form of messenger RNA (mRNA), which encodes a specific viral protein (typically the virus’s spike protein). When mRNA is delivered into the body, cells use it as a template to create viral proteins. This protein is then exhibited on the cell’s surface, resulting in an immunological response. mRNA vaccinations do not include live viruses and do not affect the recipient’s DNA.

Traditional vaccinations may contain attenuated or inactivated virus, particular viral proteins, or pathogen-derived components. Examples include the measles, mumps, and rubella (MMR) vaccination, as well as the flu and hepatitis B vaccines.