The vaccine stimulates your system, forcing him to create a natural defense against disease, in the form involving antibodies. The vaccine is actually specific to a condition, a vaccine against rabies is actually ineffective against polio... Equally, the production of antibodies gradually decreases over time, so a vaccine protects your system during a given period. After this period, the body is no longer protected and must create a booster. A serological test makes certain of acquired immunity. In the body, antibodies are produced as a result of B lymphocytes Memory M cells play an essential role because they're saving the information to combat the illness. Note: - BCG and also other vaccines do not cause antibody production but rather, they involve cellular protection. - Vaccines are administered primarily to healthy people for a vaccine can cause side effects more or less annoying. If the patient suffers from a chronic disease, only the doctor should decide vaccination, considering the risks and probable gains. My websites: Flu Vaccine and Peripheral Neuropathy |