May 19, 2025

Janessa Angela Alerre

11th Grade

George Washington High School

Throughout history, vaccines have been one of the most important and effective preventive measures to avoid getting sick. By helping our bodies build immunity, the protection against a disease, vaccines have not only saved millions of lives but also contribute to herd immunity—a form of indirect protection that occurs when a large portion of a community is immune to a disease. When enough people are immune, the spread of disease is significantly minimized, protecting even those who are not vaccinated. So, how exactly do vaccines work, and how were they created? 

Vaccines work by imitating an infection to stimulate the body’s natural defenses, helping the body learn how to defend itself from diseases. Vaccines contain weakened or inactive parts of an antigen, which is a substance that triggers an immune response, producing antibodies. The antigen could either be weakened or kill bacteria or viruses, bacterial toxins treated to make them non-toxic, and bits of their exterior surface or genetic material. Essentially, they introduce a small dose of the infection to the body. 

When your body is exposed to a vaccine via injection, white blood cells begin to produce antibodies and other molecules to identify and attack these foreign substances. These white blood cells are created in the bone marrow but are dispersed throughout the body in low numbers, ready to begin multiplying and attack. After this response, some of the white blood cells become memory cells, essentially remembering the pathogen. Thus, this would allow the immune system to react much faster and more effectively unless it encounters the pathogen again. As a result, the person becomes immunized, significantly reducing the chance of severe illness in the future.

Herd immunity plays a significant role in protecting our communities. When the majority of people in a community are vaccinated, they not only protect themselves but also others. For instance, if someone with COVID-19 is surrounded by people who are vaccinated, the disease is less likely to spread.

Many people rely on herd immunity to protect them, as there are people who are unable to receive a vaccine. These restrictions apply to people with weakened immune systems, such as those undergoing chemotherapy, individuals with HIV, newborns who are too young, the elderly, and anyone who is seriously ill. 

So, whether you realize it or not, getting vaccinated is not just about protecting yourself. It is also an important aspect of community care. Vaccines allow your immune system to build immunity against diseases, while also contributing to the safety of those around you. By choosing to get vaccinated, you are contributing to those who are unable to protect themselves. Thus, building a safer, healthier, and more resilient society. Vaccines continue to play a prominent role in future health challenges, making them one of our best advantages in fighting off diseases.