Vaccines are biological preparations that stimulate the immune system to recognize and fight specific pathogens, such as viruses or bacteria, without causing disease. They play a vital role in preventing infectious diseases by creating immunity, either through live-attenuated, inactivated, subunit, or mRNA-based formulations.

Vaccinations, the process of administering vaccines, have been one of the most effective public health interventions, drastically reducing morbidity and mortality from diseases like measles, polio, and influenza. In recent years, advancements in vaccine technology, such as mRNA vaccines, have accelerated responses to emerging infections like COVID-19.

Vaccines not only protect individuals but also contribute to herd immunity, reducing the spread of disease in populations. Ongoing research focuses on developing universal vaccines, improving delivery systems, and addressing vaccine hesitancy.