The Science Behind Protection

How Vaccines Work

Vaccines introduce a weakened or inactive form of a pathogen – like a virus or bacteria – or just a piece of it (e.g., protein) to your body.

This triggers an immune response, causing your body to produce antibodies specific to that pathogen. These antibodies ‘remember’ the threat.

Types of Vaccines

There are several types of vaccines, including inactivated vaccines (where the pathogen is killed), live attenuated vaccines (where a weakened version is used), and subunit vaccines (using only specific parts of the pathogen).

mRNA vaccines, like those developed for COVID-19, deliver genetic instructions to your cells to produce the antigen – stimulating an immune response.

Antigen → Antibody Production

Immune Memory and Long-Term Protection

After initial vaccination, memory B cells and T cells remain in your body. These ‘memory’ cells provide long-term protection.

If you encounter the actual pathogen later, these cells quickly recognize it and initiate a rapid immune response, preventing or lessening the severity of illness.

Vaccine Safety & Efficacy

Extensive testing and clinical trials demonstrate vaccine safety and efficacy. Serious adverse events are extremely rare.

Efficacy refers to the percentage of people protected by a vaccine, while effectiveness measures how well it works in real-world conditions.

Frequently asked questions

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