Survey on the Possession of HI Antibody Aganist Influenza Virus in the Aged and on the Production of This Antibody after Vaccination

Abstract

A collective health examination was carried out in inhabitants more than 40 years old of a small mountain village in August, 1981. All the examinees were inoculated with influenza vaccine, and blood samples collected from them.
The aged were examined for the p ossession of HI antibody more than 64 in titer against influenza virus strains which had been isolated from the epidemics in years before 1976. The rate of possession of HI antibody against the A/PR/8/34 strain was low, or 31.3-31.8, in the age group of 60-69 years and that of 80 years and over. It was rather high, or 70.3-70.7% and 61.9%, in the age group of 40-59 years and that of 70-79 years, respectively. The rate of possession of HI antibody against the A/Omachi/1/53 strain was low, or 12.2-43.2%, in every age group. The rate of possession of HI antibody against the A/Adachi/2/57 and the A/Aichi/2/68 strain were ratger high, or 63.8-65.6% and 71.9-76.2%, respectively, in every age group. That of HI antibody against the Hswl N1 type of the A/NJ/8/76 strain was considerably high, or 65.6-90.5%, in the age groups of 60 years and over.
The same aged were examined for the possession of HI antibody against influenza virus strains which had been isolated from the epidemics in and after 1979. The rates of possession of HI antibody against the A/USSR/92/77, the A/Kumamoto/37/79, and the B/Bangkok/1/79 strain were low, or 25.0-31.8%, 18.8-27.3%, and 23.8-31.8%, respectively, in every age group. Those of HI antibody against the B/Kanagawa/3/76 and the B/Singapore/222/79 strain were low, or 22.7-37.5% and 22.7-40.6%, respectively, in every age group.
The aged were inoculated subcutaneously with a single dose of 0.7 ml of commercial influenz vaccine ana examined for the production of HI antibody. The rates of production of HI antibody more than fourfold against the A/Kumamoto/37/79, the A/Bangkok/1/79, and the B/Kanagawa/3/79 strain were 56.0-75.8%, 48.0-58.6%, and 28.0-48.2%, respectively, in the age groups of 60 years and over. Those of HI antibody against the three epidemic virus strains, the A/USSR/9/77, the A/Niigata/102/81, and the B/Singapore/222/79, were 44.0-76.0%, 51.7-70.0%, and 32.0-64.2%, respectively.
Since the aged possessed no HI antibody against the virus strains which had caused recent epidemics, it was highly possible for them to contract infection. On the other hand, a sufficient production of HI antibody was noticed in them after inoculation with vaccine. From these results it WAS concluded that it was necessary for the aged to be inoculated positively with influenza vaccine.