How Vaccines Work
Vaccination involves introducing small quantities of dead or inactive forms of a pathogen into the body The white blood cells are now stimulated to produce antibodies against the pathogen At the same time the white blood cell produces copies of itself by mitosis When the same pathogen enters the body the white blood cells can produce correct antibodies quickly preventing infection
Herd Immunity
Unvaccinated people less likely to catch disease if large amount of population are vaccinated as there are few people who can pass the pathogen on