Antibody response and viral excretion after live polio vaccine or a combined schedule of live and inactivated polio vaccines

Effect of different immunisation schedules on the excretion and reversion of oral poliovaccine strains

“…significant (P ¼ 0.052, Fischer exact test) and is in general agreement with the results reported previously for this cohort [Ramsay et al, 1994]. There was no difference between the two arms in the number excreting type 3 virus after both doses (8 or 16% in the IPV arm compared to 7, or 12% in the OPV arm) and after neither dose (15 or 29% in the IPV arm compared to 13 or 23% in the OPV arm).…”

“…While the difference was not statistically significant it was consistent with the response to the second dose. A slight reduction in isolation of type 1 in the IPV recipients was also seen in the earlier study after the second dose of OPV compared to the OPV only cohort, but this was not statistically significant [Ramsay et al, 1994]. In the analysis described here, however, there is a striking difference in the number of children giving type 1 isolates after the second dose of OPV (14% in the IPV cohort and 43% in the OPV cohort) and in the total number of specimens yielding a type 1 isolate (9 in the IPV cohort and 46 in the OPV cohort).…”

Oral and inactivated poliovirus vaccines in the newborn: A review

“…Secondary exposure to OPV can impact a newborn's immunity since up to 50 percent of immunized babies excrete live weakened poliovirus when studied. 47 Second, the definition of the half-life of maternal antibodies may have varied. The use of a definition with a half-life longer than 4 weeks may lead to underestimation of the seroconversion rate in newborns.…”

The new vaccines in the UK: chaos or progress?

“…This adverse effect is outweighed by the better community protection it affords in addition to the provision of excellent individual immunity. This is because the OPV virus is shed from the gut of recently immunised individuals, providing constant boosting to contacts (10), while also providing local gut resistance to subsequent infection of the vaccinee with wild poliomyelitis viruses – properties not shared with the inactivated polio vaccine (IPV) which affords only individual but still excellent immunity. The risk of importation to the UK of wild polio virus has declined considerably due to the success of the WHO Polio Eradication Programme, especially in the Indian subcontinent.…”