Non-specific immunity after local immunization.

The most important advantage of local immunization is the non-specific effect. The active protection test in mice shows an immunity against oral infection with virulent Salmonella typhimurium bacteria after oral immunization with heterologous inactivated enterobacteria. We observed the same non-specific protection in a viral model. After oral immunization with inactivated S. typhimurium bacteria, the mice are protected against oral infection with a virulent parapoliomyelitis virus. In the phagocytosis test after local immunization a non-specific effect is also demonstrated. The rate of phagocytosis of macrophages against streptococci rises significantly after oral immunization or after inhalation with heat-killed S. typhimurium bacteria.