[A study on immunization of polio vaccine. I. Observation on an improved immunization schedule]

This artical reports the result of serological observation on an improved immunization schedule of polio vaccine. The result shows that a good response can be obtained by immunizing an additional dose of the vaccine on the children of 18-24 month of age.serological convertion type I of neutralization antibody can be improved from 85% up to 96%, type II from 84% to 100%, and type III from 91% to 100%, with great increase of all the three types. The study proves that the additional immunization of the vaccine will effectively control over the incidence occurrence of the children who have received three doses of the vaccine within 3 years of age. An nation-wide extensive inoculation of the vaccine among the children who have received three doses of the vaccine is suggested. 81% of neonates inoculated with the vaccine within 24 hours after birth can discharge the polio-vaccine-virus through their intestinal canal and the inoculation has some effect on the improvement of the seroconversion obtained from the immunization of the three doses of the vaccine afterwards.