Infectious immunity: This means that the body's immune system is able to fight various infectious agents such as bacteria, viruses, fungi and protozoa. Infectious immunity is the result of an active process of immunological response, consisting in the production of antibodies to the pathogen. Upon contact with a pathogen, infectious immunity manifests itself quickly and consistently, which is why it is called primary. In this case, elimination of the pathogen from the body or a long-term decrease in its number occurs (inactivation of the virus or suppression of microbial reproduction). In this case, they speak of secondary type infectious immunity. Also, the infectious immune response can be cytolytic or humoral; the latter, in turn, can be localized and systemic.