Further Analysis of National Participation in the Inactivated Poliomyelitis Vaccination Program, 1955-61

Abstract

Since 1957 the Public Health Service has sponsored annual surveys to determine nationwide participation in the inactivated poliomyelitis vaccination program which began in April 1955. These vaccination surveys were conducted in 5 successive years by the Bureau of the Census, and the results were analyzed according to various segments of the population. The proportion of the population adequately immunized has progressively in- creased since the licensure of SalK. vaccine in April 1955. By Sept. 1961, 77% of the population under 40 years of age had received at least 1 inoculation, about 67% had received 3 or more inoculations, and 40% had received the 4th or booster inoculation. Approximately 60% of school-age children had 4 or more doses of inactivated poliomyelitis vaccine by Sept. 1961, but less than half of the preschool children and young adults and less than one-quarter of the men had reached this level. The response of preschool children, adult males, and lower socioeconomic groups has been well below the participation of school-age children, adult females, and higher socioeconomic groups respectively. Since the advent of the inactivated poliomyelitis vaccine in 1955, poliomyelitis has attacked these poorly immunized groups with greater frequency. Estimates of the effectiveness of 3 or more doses of inactivated poliomyelitis vaccine, as studied in 4 recent epidemics, have ranged from 77 to 82%. The sharp drop in poliomyelitis incidence since 1955 can largely be attributed to the use of the inactivated vaccine.