1967 Volume 33 Issue 6 Pages 555-563
In the prevention of viral diseases, vaccine plays a very important role as prophylactic means for susceptible hosts. In the case of influenza, where the etiological virus has been undergoing changes in antigenic structure, it is necessary to select a viral strain most suitable as antigen for vaccine or to be careful about the use of such strain. The author studied this subject on the basis of the antibody retained by hosts and the development and behavior of such antibody. The present investigation was carried out the inhabitants of a rural area where it was presumed that an epidemic of influenza would occur only to disappear where it was presumed that an epidemic of influenza would occur only to disappear within a short period of time, withrout causing any marked confusion. These inhabitants were inoculated with influenza adjuvant vaccine. Francis's Original Sin Theory on antigen was applied. Sero-epidemiological examination was conducted on the state of maintenance of antibody prior to inoculation and the development and behavior of antibody three months after inoculation. The following results were obtained from this examination. The vaccine used was a polyvalent one composed of four strains of type A, including the classical Aswine/31 strain, and three strains of type B. All these strains, except the Aswine/31 strain which was of porcine origin, were proved to be available as vaccine with satisfaction, giving rise to sufficient antibody. It was assumed that the Aswine/31 strain might indicate the limit of use a strain of animal origin. This strain is considered to have the same antigenic structure as the etiological virus of Spanise influenza and gives rise to the phenomenon of Davenport in some age group of inhabitants inoculated. There was nothing specific observed in the behavior of f he viral sf rains of A0 and A1 Fypes used. These strains showed gradual morphologicalchanges in the course of antigenic variation. Such specificity as considered to produce any antigenic variant type was not exhibited either in the behavior of the strains Btype. The Taiwan strain, which had had no connection with any outbreak of influenza in Japan, presented a strong behavior when inoculated into the inhabitants of such age groups as exceeding forty years. Accordingly, this strain seems to have revealed a specificity of changes in antigenic structure among the strains of B type used. From the results mentioned above, it is concluded that in f he control of influenza, vaccine should be prepared from the viral strain which was prevalent in some past outbreak and epidemic in every age group of people and which has undergone variation in antigenic structure. In this case, it is necessary to select an antigen suitable for each age group of people. It is also possible to predict the effect of antibody production from a sero-epidemiological point of view.