In a sense, the vaccine tricks the body into thinking it is under assault, and the immune system makes weapons that will provide a defense when a real infection becomes a threat (AAP, 2015). Vaccines are made up of dead forms of the bacteria or virus that causes a disease. The disease have to be killed a certain way in order for this process to actually work. Although sometimes, an inactivated toxin created by the bacteria or virus is used. When you receive a vaccination, your body reacts to this organism just as it would react if a full blown infection of this disease occurred. Your body creates antibodies that stay in the body and protects the body just in case a actual for of this disease attacks. To repeat, the vaccine-generated antibodies stay in your child’s bloodstream and are prepared to fight off infections for months, years, and even a lifetime (AAP, 2015). This is proven to work through zelous research. Vaccines undergo a rigorous review of laboratory and clinical data to ensure the safety, efficacy, purity and potency of these products. Vaccines approved for marketing may also be required to undergo additional studies to further evaluate the vaccine and often to address specific questions about the vaccine's safety, effectiveness or possible side effects (FDA, 2006). For these reasons, you never have to worry that your vaccine will not