The antibodies circulate in the bloodstream. About 1 or 2 of every 20 people immunized will not have an adequate immune response to a vaccine. This means that when there is a disease outbreak, the very small number of people for whom the vaccine did not work may still be able to catch the disease. Regardless, those who have not received the vaccine are much more likely to catch the disease. It is much better to gain immunity from a vaccine.
Diseases cause suffering and, in some cases, permanent disability or death.
Vaccines allow a person to be protected from the disease without experiencing the serious adverse effects of that illness. In addition, brain damage can result from measles, Hib meningitis, or pertussis. If a woman gets rubella while pregnant, her baby could have serious birth defects. For some vaccines, such as tetanus and Hib, the vaccine is sometimes better at creating immunity than a natural infection would be. There are very real risks from not receiving vaccinations.