How do vaccines work?

Chapter 9

Vaccines protect people from diseases. They have even been able to eradicate small pox from the earth, a disease that was once ran rampant on earth. Vaccines prevent a lot of diseases that cause death, disabilities and in the end they save money. 

When we are born, we are born with the ability to develop an immune system. The immune system is composed of many cells that patrol around in our fluids, organs and other tissues looking for foreign material/antigen. When the immune system comes in contact with a foreign invader/antigen, it makes antibodies against that antigen and some of those antibodies have the ability to store memory, just in case that same invader comes around again. These are called memory cells and they serve to fight a re-infection. 

Vaccines assist the immune system, because they contain certain antigens that belong to a pathogenic disease. Not to worry these antigens found in vaccine are either killed or weakened, they are not strong enough to cause disease but they certainly are enough to engage our immune system. Once we engage the immune system with our antigens from the vaccine, we make antibodies against them. And like we said before some of these antibodies form into memory cells, so if we ever get infected with that same pathogen in the future we would be able to readily fight the infection. This is a general description about the way vaccine prevent diseases. All in all, vaccines are very beneficial to humans because they allow us to fight an infection without ever actually getting the disease or feeling sick.