MCV1 coverage, DTP1 coverage, composite coverage, zero-dose prevalence, Demographic and Health Surveys, Multiple Indicator Cluster Survey, Bayesian geostatistical modelling, Bayesian multilevel modelling, zero-dose, equity, immunization, targeted surveys, measurement, subnational immunization coverage, under-immunized children, immunization inequality, zero-dose children, COVID pandemic, health inequality, maternal and neonatal tetanus, vaccination, health disparities, coronavirus pandemic, immunization coverage levels, diphtheria–tetanus–pertussis-containing vaccine, vaccination of newborns, tribal populations, COVID-19 vaccination, India, implementation science, case study, community-based strategies, COVID-19, immunizations, pediatric COVID-19 vaccines, vaccine hesitancy, vaccine confidence, pandemic, National Immunization Survey—Child COVID Module, children, geographic accessibility, vaccine demand, gender, immunization coverage, LMICs, inequality, data visualization, capacity building, surveillance, health equity, life course, 2YL, catch-up vaccination, missed opportunities for vaccination (MOV), vaccination timeliness, age appropriate, quality improvement, Ghana, EPI, measles, measles-containing vaccine, MCV1, MCV2, second year of life, dropout rate, barriers, Oromia, Ethiopia, vaccine pricing, inequitable vaccine uptake, fair prices, pricing policy, health inequalities, infant and child health, scoping review, History, Social and ethical issues

The 2024 Special Issue of Inequality in Immunization collates 14 global research and review contributions that spotlight differences in the attainment of immunization coverage across population groups, capturing findings pertaining to various types of immunization (including COVID-19 and childhood immunization). The articles pose key questions about methodological and definitional issues, such as how to standardize and adapt framing to measure zero dose and how to measure the significance of parental hesitancy in exacerbating inequalities. The contributions within this Special Issue range from research studies that are global in scope to analyses focused on national and subnational settings. This collection represents some of the latest state-of-the-art scientific works on inequalities in immunization available in 2024, with contributions from a range of academics, scientists, and implementers involved in networks of and collaboration between the World Health Organization, Gavi, the Vaccine Alliance, as well as the US Centers for Disease Control.