Viruses as nonspecific modulators of immunological reactivity.

As shown experimentally and by examination of patients, numerous DNA and RNA viruses induce transitory nonspecific changes in the immune response of the host to heterologous antigens. Attenuation does not affect this property of the parent strains. Nonspecific immunomodulation is connected with disturbed functions of B and T lymphocytes, macrophages and haemopoietic cells. The actual mechanisms of immunomodulation differ in different infections.