VII. Reactions to the Oral Vaccine ‡

As described in earlier papers in this series, approximately 10,000 persons, mainly children between the ages of 3 months and 18 years, were given the Sabin oral poliovirus vaccine in Middletown, Connecticut, early in 1961. Among the objectives of the program was the detection of any contra-indications or untoward effects which might follow the use of the oral vaccine. The following discussion deals with observations made on these points. REACTIONS REPORTED Shortly after the first dose of monovalent type I vaccine had been given, one of us (M.L.P.) as Director of Health of the city, received reports of a few possible "reactions." An investigation was therefore carried out at once to discover the frequency and nature of these suspected reactions. Telephone calls were made to local pediatricians and to the two pediatric allergists, and a form letter was sent to all practicing physicians in the city, asking for details on any children seen with complaints which might be related to vaccine ingestion. In addition, district nurses and school nurses were asked to report any symptoms in vaccinated children which came to their attention. Physicians and nurses were again requested to notify the health officer of any difficulties following the second dose of oral vaccine. Fourteen children were reported to have suspected post-vaccinal reactions after the first dose, and three after the second. Of the 14, 11 took the second dose, in all cases without ill effect. The three reported reactions after the second dose were in children who had taken the first without incident.