Journal Article

Geospatial variation in measles vaccine coverage through routine and campaign strategies in Nigeria: Analysis of recent household surveys

Pannell, Oliver, Rhoda, Dale A., Cutts, Felicity T., Tatem, Andrew J., Utazi, C. Edson, Wagai, John, Adeniran, Adeyemi, Dieng, Boubacar, Oteri, Joseph, Ferrari, Matthew J., Danovaro-Holliday, M. Carolina

2020

Overview

•Three surveys since 2013 show persistently low MCV coverage in much of northern Nigeria.•The 2017–18 measles SIA reached higher and more homogeneous coverage than seen previously.•Geospatial differences exist in the SIA’s reach of previously unvaccinated children.•Nearly all the country is far from the goal of 95% coverage with ≥ 2 doses of MCV.•Routine services need strengthening nationwide, especially in the north. Measles vaccination campaigns are conducted regularly in many low- and middle-income countries to boost measles control efforts and accelerate progress towards elimination. National and sometimes first-level administrative division campaign coverage may be estimated through post-campaign coverage surveys (PCCS). However, these large-area estimates mask significant geographic inequities in coverage at more granular levels. Here, we undertake a geospatial analysis of the Nigeria 2017–18 PCCS data to produce coverage estimates at 1 × 1 km resolution and the district level using binomial spatial regression models built on a suite of geospatial covariates and implemented in a Bayesian framework via the INLA-SPDE approach. We investigate the individual and combined performance of the campaign and routine immunization (RI) by mapping various indicators of coverage for children aged 9–59 months. Additionally, we compare estimated coverage before the campaign at 1 × 1 km and the district level with predicted coverage maps produced using other surveys conducted in 2013 and 2016–17. Coverage during the campaign was generally higher and more homogeneous than RI coverage but geospatial differences in the campaign’s reach of previously unvaccinated children are shown. Persistent areas of low coverage highlight the need for improved RI performance. The results can help to guide the conduct of future campaigns, improve vaccination monitoring and measles elimination efforts. Moreover, the approaches used here can be readily extended to other countries.

• Publisher: Elsevier Ltd,Elsevier Limited,Elsevier Science
• Subject: Allergy and Immunology / Bayes Theorem / Bayesian analysis / Bayesian theory / Child, Preschool / Children / Children & youth / Estimates / Geographic information systems / Geography / Geospatial analysis / household surveys / Households / Humans / Immunization / Immunization Programs / Infant / Mapping / Mathematical models / Measles / Measles - epidemiology / Measles - prevention & control / Measles vaccine / Measles Vaccine - administration & dosage / monitoring / Nigeria / Polls & surveys / Post-campaign coverage survey / Regression analysis / Regression models / Routine immunization / Spatial Analysis / Supplementary immunization activities / Vaccination / Vaccination Coverage / Vaccines