Inactivated poliovaccine: adverse reactions and antibody responses.

Adverse reactions and antbody responses after inactivated poliovaccine were studied in 380 children. Fever reaction (greater than or equal to 37.5 degree C rectally) was recorded in 14% of children after the first poliovirus vaccination and in 19% after the second. Restlessness was reported in 15% and 14% of the chidren. Fever reaction exceeding 38.5 degree C was seen in 5% of the vaccines. Before the first vaccination at the age of six month 29% of the 48 children had antibodies against poliovirus type 1 and 2 and 43% against type 3. The first vaccination induced no significant changes in antibody titers. After the second vaccination antibody responses were low and 35%, 9%, and 35% remained seronegative to types 1, 2 and 3, respectively. After the third vaccination at the age of two years the respective geometric mean titers were 1:67, 1:335 and 1:48. No measurable antibodies were found to type 1 in 23%, to type 2 in 2%, and to type 3 in 10%. Only one child was triplenegative. All seronegative children were revaccinated and in all vaccinees a seroconversion ocurred two weeks after the booster dose. The combination of inactivated poliovaccine to DPT (Diphtheria, Tetanus, Pertussis) vaccine induced no significant change in poliovirus antibodies or in adverse reactions.