How Do Vaccines Really Work ?
Discovery of vaccines
In the 18th century around 300 million people died due to the outbreak of a fatal illness. This disease, which has now been eradicated but was once one of the deadliest diseases known to man. Smallpox was both a bane and boon for humanity. It caused suffering to millions however, it also led to the discovery of vaccines.
In 1796 the scientist Edward Jenner injected material from a cowpox virus into a boy thinking that this would provide the protection needed from the outbreak of the Smallpox virus. He was successful in his endeavor. The boy was immunized against the disease and thus, the world's first vaccine was discovered!
Terms to know:
Pathogen: a bacterium, virus, or other microorganism that can cause diseases.
Antigen: A subpart of a Pathogen.
Antibody: A type of protein produced by the body in response to Pathogens.
Plasma Cells: A type of cell that makes large amounts of a specific antibody.
The Body's Natural Response
Different types of pathogens cause certain diseases, when the body’s immune system gets infected with a pathogen we fall sick.
A subpart of a pathogen is known as an Antigen. It is a foreign substance such as bacteria, viruses, allergens etc. which makes us fall sick and triggers an immune response.
When an antigen comes in contact with Plasma cells, these Plasma cells clone and create millions of antibodies. Antibodies act like soldiers inside the body protecting it from harmful diseases.
When the human body is exposed to an antigen for the first time, it takes time for the immune system to respond and produce antibodies specific to that antigen. In the meantime, the person is susceptible to becoming ill.
Once a person’s body creates Antibodies, the immune system works with them to fight off the Antigen and stop the disease. The human body also produces memory cells which remain alive even after the Pathogen dies. So, the next time the same Pathogen attacks the body the immune system acts faster and more effectively because the memory cells produce antibodies against the disease, hence protecting the body.
How Vaccines Help
Using the same principles that the body uses to defend itself; scientists use vaccines to trigger the body's Immune system, without exposing the human to the full strength of the disease. The weakened and inactive Pathogen is injected into the body to trigger an Immune response, teaching the body to recognize an attack by making a profile of that pathogen or any pathogen similar to it in preparation.
Over the years research has resulted in many vaccines, which each work uniquely and are separated into many different types such as Inactive vaccines which are made from a weaker version of the pathogen and Subunit vaccines which are made from just the Antigen etc.
Vaccines changed the world as we know it! They made a huge impact on the field of medicine and gave rise to endless possibilities. Modern medicine will continue to make life changing discoveries similar to vaccines and completely transform the world and how it functions.
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