[Immune interference of enteroviruses to immune response of TOPV in subtroptical areas]

To study whether enteroviruses interfere with the immunoeffect of TOPV in subtroptical areas, a total number of 188 children were investigated 82 in summer, 106 in winter in two townships of Hui Dong County from 1992 to 1993. The carrier rates of enteroviruses and serum nutralization antibody titres of polio were tested before and after the children were vaccinated with TOPV. Data showed that the GMTs of poliovirus type I, II, III in winter were 2 to 7.1 times as much as those in summer after administration of one and three doses TOPV. Enterovirus carrier rates were 75.6% and 38.8% respectively in summer and winter before vaccination in health children. The GMTs of polio serum antibody in children without enteroviruses was 1.5 to 1.7 times as much as the GMTs of those with enteroviruses, and the difference was statistically significant. Overall, the results demonstrated that enterovirus infection interfered the immune response of vaccinates to TOPV to some extent. It was also suggested that supplemental immunization was the key measure in polio eradication program and should be conducted in winter or spring seasons.