THE CURRENT STATE OF IMMUNITY TO POLIOVIRUSES IN NEW SOUTH WALES

Abstract

Sera from 1,677 subjects aged between 4 months and 64 years were tested for neutralizing antibodies to poliovirus types 1, 2 and 3. Type 1 antibody was found in 82%, type 2 in 86% and type 3 in 80%. Complete immunity was found in 64% of subjects tested. Four per cent possessed no antibodies to any serotype, and the remainder (32%) showed only partial immunity (that is, possession of only one or two antibody types). It was found that 22% of children in the 0 to 4 years age group had no demonstrable antibodies to any serotype, and in the first year of life this figure was 37%, which suggests that the recommended schedule for vaccination Is not being observed by many parents. Current antibody incidence has been compared with that found in 1955 from a survey carried out in Melbourne before the introduction of Salk vaccination. It Is considered that greater publicity should be given to the need for poliovirus vaccination of children under the age of five years, and that regular antibody surveillance be carried out on children in this age group.