[Immunological problems of influenza virus infections]

Reference is made to results reported in literature as well as to some of the author's own findings for a summary account of specific immune responses to influenza virus infections. Some introductory comments on the correlations that exist between morphology and function of structural components of the influenza virus as well as on the pathogenesis and its relevance to the immunological responses are followed by a description of the humoral immune response. An assured correlation has been found to exist between the titres of hemagglutination-inhibiting antibodies with responses specific of subtypes and of strains for the protection against homologous influenza virus infection in terms of prevention of outbreak or mitigation of the pathological course. Anti-neuraminidase antibodies have influence upon virus expansion in the organism and in the given population as well as upon the severity of the disease. Particular importance has been attributed to the secretory immunoglobulins. Used in conjunction with interferone, they obviously had an infection-preventing function, wheras the primary role of serum anibodies was a reduction of severity. The studies into cell-mediated immune responses were much less intensive than those conducted into antibody formation. Cell-mediated immune response is thought to emanate from induction of hemagglutinin and is directed against the latter. Sufficient results have not become available as yet on the importance of cellular immune response to protection.