Some diseases can be treated with antibiotics. Vaccinations allow protection against specific diseases, but the level of protection depends on the amount of people vaccinated.
Pathogens are microbes that cause diseases. Vaccines allow a dead or altered form of the disease causing pathogen to be introduced into the body, which contain a specific antigen. This causes the immune system, specifically the white blood cells, to produce complementary antibodies, which target and attach to the antigen. When a white blood cell engulfs and digests a pathogen it is called phagocytosis.
During the primary infection the antibodies slowly increase, peak at around ten days and then gradually decrease. A second exposure to the same pathogen causes the white blood cells to respond quickly in order to produce lots of the relevant antibodies, which prevents infection.