A 15-month-old girl from Delhi is brought to the immunisation clinic by her mother. The child's immunisation card shows: BCG at birth, DPT-1 and OPV-1 at 6 weeks, DPT-2 and OPV-2 at 10 weeks, and DPT-3 and OPV-3 at 14 weeks. The mother states she has been unable to bring the child for follow-up visits due to family circumstances. On examination, the child is healthy with no contraindications to vaccination. According to the current UIP schedule, what is the most appropriate next step in immunisation?

Explanation

## Catch-Up Immunisation and Booster Schedule at 15 Months **Key Point:** This child has completed the primary series (DPT-1, DPT-2, DPT-3 at 6, 10, 14 weeks) and is now due for the **first booster dose** at 15–18 months of age. According to the current UIP schedule, this booster consists of **DPT Booster-1 and OPV Booster**. ### UIP Schedule: Primary Series vs. Boosters | Age | Vaccine | Dose | Notes | |-----|---------|------|-------| | Birth | BCG, OPV-0, Hepatitis B-0 | Birth doses | | | 6 weeks | DPT-1, OPV-1, IPV-1, Hib-1, PCV-1, Rotavirus-1 | Primary-1 | | | 10 weeks | DPT-2, OPV-2, IPV-2, Hib-2, PCV-2, Rotavirus-2 | Primary-2 | | | 14 weeks | DPT-3, OPV-3, IPV-3, Hib-3, PCV-3 | Primary-3 | | | **15–18 months** | **DPT Booster-1, OPV Booster** | **Booster** | After completing primary series | | 5–6 years | DPT Booster-2, OPV Booster | Second booster | | **High-Yield:** Under the **current UIP (Universal Immunisation Programme)** schedule as published by the Ministry of Health & Family Welfare, Government of India, the booster at 15–18 months includes **DPT Booster-1 and OPV Booster**. IPV is given as part of the primary series (at 6, 10, and 14 weeks) but is **not** listed as a separate booster dose at 15–18 months in the standard national UIP schedule. The IPV-dominant strategy applies to the primary series; OPV booster at 15–18 months remains part of the national schedule. ### Why This Child is Ready for Booster 1. **Primary series complete:** BCG at birth ✓, DPT-1/OPV-1 at 6 weeks ✓, DPT-2/OPV-2 at 10 weeks ✓, DPT-3/OPV-3 at 14 weeks ✓ 2. **Age appropriate:** 15 months falls within the 15–18 month booster window ✓ 3. **No contraindications:** Child is healthy ✓ 4. **Booster due:** DPT Booster-1 + OPV Booster ✓ **Clinical Pearl:** Catch-up vaccination does NOT mean restarting the series. Once the primary series is complete, the child moves directly to the booster schedule. There is no need to re-administer DPT-1, DPT-2, DPT-3 (making Option B incorrect). Deferring vaccines until 18 months (Option D) is also incorrect — the booster window opens at 15 months and should not be unnecessarily delayed. ### Why Option C is Incorrect Option C states "DPT Booster-1 and **IPV Booster**." While some updated references discuss IPV boosters, the **standard national UIP schedule** (Park's Textbook of Preventive and Social Medicine, 26th edition; MoHFW UIP guidelines) lists the 15–18 month booster as **DPT Booster-1 + OPV Booster**, not an IPV booster. Substituting OPV with IPV at this stage is not part of the officially published national schedule and would be incorrect in the context of a UIP-based question. **Reference:** Park's Textbook of Preventive and Social Medicine, 26th Ed.; MoHFW National Immunisation Schedule, Government of India.