Peer-reviewed article
Routine Childhood Immunisation Coverage and Dropout Rates at a Tertiary Hospital in South-South Nigeria: A Four-Year Retrospective Review (2022–2025)
C.B. Nwadiaru, I.E. Anika, L.U. Asamudo, C.A. Ukwu ·
Summary
Written by AI, not yet AICS's view · claude-sonnet-5This study looked at four years of immunisation records from a hospital clinic in Port Harcourt, Nigeria, covering children under two years old. It found that overall vaccine coverage was generally high but changed over time, dipping in 2023 and again in 2025. Vaccines given at birth or six weeks, like BCG and the first dose of Penta, had the best uptake, while later vaccines such as measles, yellow fever, rotavirus and IPV were less consistently completed. Dropout rates between early and later doses of the same vaccine series remained a problem, especially between BCG and measles vaccination.
Key points
- 37,685 immunisation visit records were reviewed from 2022 to 2025
- Female children accounted for 53.4% of visit records, male for 46.6%
- Coverage declined in 2023, rose in 2024, then fell again in 2025
- BCG, OPV0, HBV0, Penta1 and PCV1 (early-schedule vaccines) had the highest and most consistent uptake
- BCG-to-measles dropout rates stayed high and fluctuated throughout the study period
Limitations
The study only reflects one hospital's administrative records, so it may not represent immunisation patterns across the wider region or country, and it does not explain the reasons behind the observed coverage changes or dropouts.
Abstract
Background: Routine childhood immunisation is central to child survival in Nigeria, yet coverage and completion vary across settings and over time. Facility-level evidence is needed to assess programme performance during disruption and recovery. Objectives: This study reviewed routine childhood immunisation coverage and dropout rates at the University of Port Harcourt Teaching Hospital (UPTH), a tertiary hospital in South-South Nigeria, from 2022 to 2025, identified vaccines with consistently high uptake, and assessed schedule completion between Penta1-Penta3 and BCG-measles. Methods: A retrospective descriptive analysis was conducted using routine immunisation registers from the Family Health Clinic, UPTH. All children aged 0-23 months vaccinated between January 2022 and December 2025 were included. Administrative coverage rates were calculated for each antigen, and monthly dropout rates were estimated for Penta1-Penta3 and BCG-measles. Results: A total of 37,685 immunisation visit records were reviewed. Male children accounted for 17,570 (46.6%) visit records, while female children accounted for 20,115 (53.4%). Administrative coverage estimates were generally high but varied over time, with a decline in 2023, an increase in 2024, and a subsequent reduction in 2025. Vaccines administered at birth and at 6 weeks of age, including BCG, OPV0, HBV0, Penta1, and PCV1, consistently had the highest uptake. In contrast, vaccines administered later in infancy, including rotavirus vaccine, inactivated polio vaccine (IPV), measles vaccine, yellow fever vaccine, and meningococcal A conjugate vaccine (MenA), showed greater variability. Penta1–Penta3 dropout rates were slightly above the recommended threshold in 2022, improved in 2023, and increased in 2024, while BCG–measles dropout rates remained high and fluctuated throughout the study period. Conclusion: Facility administrative immunisation coverage estimates at UPTH remained generally high, although completion across the schedule was inconsistent, particularly for rotavirus, inactivated polio, measles, yellow fever, and meningococcal A conjugate vaccines. Strengthening follow-up systems and defaulter-tracking may improve completion rates.