If a 11-month old child has received two doses of DPI and polio, comes for further immunization after 5 months of the last dose, what should be done ?
**Core Concept**
The question is testing the understanding of the immunization schedule for polio, specifically the dosing interval and the use of the Diphtheria, Pertussis, and Tetanus (DPT) vaccine in combination with the poliovirus vaccine. The correct approach involves understanding the guidelines for revaccination and the administration of booster doses.
**Why the Correct Answer is Right**
The child received two doses of DPT and polio, but the exact type of poliovirus vaccine (OPV or IPV) is not specified. Assuming OPV, the standard schedule for OPV is 6, 10, and 14 weeks of age, with a booster dose at 16-18 months. Given that the child is 11 months old and has already received two doses, the next dose should be administered at the recommended interval, which is typically 4-6 weeks after the last dose. However, since the child is already 11 months old, waiting for the usual 4-6 week interval may not be feasible. In this scenario, the child should receive a catch-up dose to ensure protection against polio.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not provide a clear direction for the next steps in immunization. The child needs a specific schedule and dose to complete the immunization series.
**Option B:** This option is incorrect because it does not account for the child's age and previous immunization history. The child should receive a catch-up dose to ensure protection against polio.
**Option C:** This option is incorrect because it does not provide a clear direction for the next steps in immunization. The child needs a specific schedule and dose to complete the immunization series.
**Clinical Pearl / High-Yield Fact**
For children who have received incomplete or delayed immunization schedules, it is essential to assess their individual risk factors and provide catch-up doses as necessary to ensure protection against vaccine-preventable diseases.
**Correct Answer:** B. Administer a catch-up dose of OPV.