Abstract
Background
Bangladesh is the 8th most populous country in the world. Possessing one of the highest rates of urbanization, over the last 40 years the proportion of the population living in urban areas in Bangladesh has increased from 5% to 28% with over 45 million people living in urban areas. The growing urban population puts additional pressure on already weak infrastructure in cities like Dhaka, resulting in the creation of slums. Effective and equitable vaccination coverage strategies that take into account slum settings has become vital to reducing outbreaks and the burden of child morbidity and mortality from infectious disease, especially within high population density communities. According to the national EPI coverage evaluation survey in 2016, the children in slums have lower rates of immunization – 67% compared to the national rate of 82%.
Methods
Primary data collection
Inequities in full vaccination coverage were examined through household surveys with caregivers of children aged 12-23 months. The study was conducted in urban areas (slum Kawran Bazar, non-slum Kawran Bazar, slum-Bandar, non-slum Bandar) and rural areas (Bancharampur Upazila and Dhamrai Upazila).
Equity Analysis
The Equity in coverage of the vaccines was analyzed through the Vaccine Economics Research for Sustainability & Equity (VERSE) tool. This toolkit generates a composite equity concentration index that accounts for multiple factors associated with inequities in vaccination status (maternal education level, sex of the child, child age, household wealth, urban/rural designation, geopolitical location, and insurance coverage influencing equity). The tool also runs a decomposition analysis that evaluates the contribution of each factor to vaccine coverage.
Results
The coverage of vaccines in our study is comparable to the national estimates, with most vaccines having a coverage of over 82%. The concentration index for fully immunized for age is 0.121 with an absolute equity gap of 0.195, showing that childhood immunization would have to increase by 19.5 percentage points to have comparable fully immunized for age coverage between the most and least advantaged quintiles in our sample. The rural districts are the highest performing districts in our sample; Brahmanbaria and Dhaka districts have the highest levels of fully immunized for age children and equity. Decomposing the drivers of inequity for fully immunized, urban/ rural (which accounts for slum and non-slum in urban areas) is the primary driver, accounts for 71% of the variation in immunization status, even after controlling for socioeconomic status and maternal education suggesting supply-side barriers to access. Decomposing the equity in coverage for BCG and Penta3, similar trends are observed, with urban/rural status or districts being the major drivers of inequity.
Conclusion
Overall, Bangladesh has achieved high coverage rates for most vaccines. However, to sustain the health gains from vaccinations and contain potential future outbreaks, special attention and health interventions will need to target urban areas, especially urban slums that are lagging behind in vaccinations. Evidence from our study suggests that even after controlling for wealth and education, urban/rural (including slum and non-slum) designations remain important drivers of inequity in the coverage of vaccines in Bangladesh.