Immuno-Epidemiological Analysis of Viral Infections, Particulalry
Concerning the Incidence of Influenza HI Antibodies
1966 Volume 40 Issue 5 Pages 129-144
Details
1966 Volume 40 Issue 5 Pages 129-144
Sera from healthy adult inhabitants of Tokyo were periodically collected and examined by hemagglutination inhibition (HI). Immunological observations were temporally made on the community's antibody level against influenza viruses. The data obtained was then plotted by a new diagrammatic method that utilized regression analysis. The equation y = a +bx expresses the curve obtained.
Results:
1) The actual data of the sample were within 20-80% of the cumulative positive rates, andfitted the computed value of the regression line. Thus a regression line that represents a sample should be fixed by both the y value (cumulative positive rate) and x value (antibody titer) on the Y and X axis. It was thus considered a more convenient method for precise analysis of the antibody incidence as well as its titer level. The previously employed method expressed antibody titer by the frequency distribution of the maximal antibody titer or the cumulative positive rate at a certain indicated titer.
2) Periodic movements of the regression line with the same viral antigen suggest activity of this virus in the community. A sudden increase of the y value indicates an increase in the newly infected population. An inclination followed by a declination of the regression line indicate delayed antibody response to virus invasion.
3) Interpretation of the data as shown on the regression curve agreed with the actual prevalence of influenza among school children at the time of its outbreak as well as with the type of virus concerned and the duration of the epidemic.
4) It was also possible to define a secondary etiological virus, annexed to the prevalent type of virus by regression analysis.
5) Changes in the prevalence of influenza viruses since 1963 may have occurred viz., during the A2 type epidemic in 1965, a slow and minor increase of the y value followed by a remarkable increase of the x value in the regression line was observed. This was quite different when compared with cases which occurred before 1962. This tendency was also observed in B type epidemics
