Reintroducing OPV in Israel on the journey to global polio eradication - Estimation at a low rate of contraindicated population.

Introduction: The 2013 reemergence of wild poliovirus in Israel led to the reinstatement of a routine OPV vaccination. Fearing VAPP in immunocompromised, the MOH regulated contraindications for vaccination candidates and household contacts. In this study we estimate the size of the contraindicated population to OPV vaccination.

Method: We studied vaccination candidates aged 2-9 and 14-23 months and probable household contacts. Using the rate of contraindications extracted for each study group from a medical records database, a statistical model was built to estimate the probability of contraindications in candidates.

Results: 3.9% of the 2-9-month-old study group and 4% of the 14-23-month-old group had contraindications by either self or household contacts.

Conclusion: A statistical model can provide an estimation of the contraindicated population and can be used in the future when devising vaccination campaigns. In contrast to concerns raised by the MOH, our findings show a smaller than anticipated contraindicated population.