Immune response to intradermally injected inactivated poliovirus vaccine

Immune response to intradermal inoculation of a fractional dose of inactivated poliovirus vaccine (IPV) was measured in 8 adults and 10 children who were previously immune. A striking 4-fold to 1024-fold antibody booster response to all 3 poliovirus serotypes was found in 15 subjects and a similar response to 2 poliovirus serotypes occurred in the other 3 children. Induration and erythema of 3 mm diameter or above, indicative of a cell-mediated immune response, was seen in 12 subjects. Intradermal inoculation of IPV may be a useful technique for secondary immunisation programmes against polio and its use for primary immunisation merits investigation.