Zero-dose vaccination status among children in Malawi: patterns, predictors, and geographic hotspots

Zero-dose children, defined as children who have not received any routine vaccination, are an important indicator of inequity in immunisation systems. Although Malawi reports high national vaccination coverage, little is known about the characteristics and spatial distribution of children who remain unvaccinated. We examined the determinants and geographic patterns of zero-dose status in Malawi. We analysed data from the 2015-16 Malawi Demographic and Health Survey, including 681 children aged 1 to 35 months. Zero-dose status was defined as receiving no routine childhood vaccine in this analysis. Descriptive analyses and mixed-effects logistic regression were used to identify factors associated with zero-dose status, while adjusting for clustering at the enumeration area level. A binomial geostatistical model was applied to map fine-scale spatial variation across the country. Overall, 8.1% of children (n = 55) were zero-dose. Younger children were more likely to be unvaccinated, with one third of zero-dose children aged 1 to 11 months. In adjusted analyses, children aged 12 to 23 months and those aged 24 months or older had significantly lower odds of being zero-dose compared with children aged 1 to 11 months. Home delivery strongly increased the likelihood of being zero-dose (AOR = 4.28; 95% CI: 1.31 to 14.01). More than one antenatal care visit was associated with substantially lower odds of zero-dose status (AOR = 0.06; 95% CI: 0.01 to 0.31). Spatial modelling identified high-prevalence hotspots in Karonga, Nkhatabay, Nkhotakota, Mangochi, and parts of Chikwawa. Zero-dose children in Malawi are concentrated among those with limited maternal health system contact and in specific geographic areas with persistent access barriers. Strengthening antenatal and delivery services, improving early postnatal follow-up, and deploying spatially targeted outreach can help address these inequities and accelerate progress toward national and global immunisation goals.