Asked in Immune System
Must the human body become sick to produce antibodies against a pathogen?
No. Many organisms are harmless, and the body will produce antibodies since the organisms are seen as foreign.
Many pathogens (harmful organisms) may not cause significant disease in many people. An example would be the poliovirus - in some people it causes paralysis; in others it causes minor illness, in others it causes no symptoms. In all cases, the person develops antibodies.
Vaccination exposes the person to the antigens without the pathogen being present, and so antibodies are formed before the exposure, and this process does not result in illness.