Abstract
Not receiving a DPT-containing vaccine in early childhood indicates an absence of routine immunization, which puts children at an elevated risk of mortality, morbidity, and worse human development over the life course. We estimated the percentage of children 12-35 months who did not receive a dose of DPT-containing vaccine (termed zero-dose children) using household surveys from 81 low- and middle-income countries conducted between 2014 and 2023. For 68 countries with more than one survey (with the earlier survey conducted 2000-2013), we estimated the average annual percentage point change in prevalence of zero-dose children between the earliest and latest surveys. We also explored the association of zero-dose prevalence with postneonatal and child mortality, health expenditure, and Gavi-eligibility. Overall, 16% of children in our pooled sample had not received a dose of DPT-containing vaccine. There was a 0.8% point decline in zero-dose prevalence per year on average across the period studied. A single percentage point average annual decline in zero-dose prevalence was associated with an average annual decrease of 1.4 deaths in the postneonatal and childhood period per 1000 live births. Gavi-eligible countries had a much faster decline in zero-dose prevalence than other countries. Large gains have been made in reducing the percentage of children who did not receive a DPT-containing vaccine. Efforts to reduce the number of zero-dose children should focus on countries with high prevalence to achieve the Immunization Agenda 2030. Healthcare spending could be prioritized so that the prevalence of zero-dose children is reduced.