Canaries in Coal Mines: Impact of Delaying DPT1 on Vaccination Coverage in India

Zakir Husain, Presidency University

Operationally defined as children who did not receive DPT1, zero dose children have emerged as an important concern in immunization programs. The failure to deliver DPT1 has a cascading effect on other vaccines. Timing of vaccination is also important, as vaccine delays reduce coverage of subsequent vaccines and increase Vaccine Preventable Disease-related morbidity and mortality in children. The present study examines the impact of delaying DPT1 on the uptake of subsequent vaccines in India, focusing on gender and rural-urban inequality. The econometric analysis comprises of estimating selection models: regressing delay in DPT1 in model 1 on determinants, and regressing uptake of subsequent vaccines on a dummy for delay in DPT1. An endogenous treatment effects model is also estimated to check robustness. The present study uses data on children aged 0-35 months provided in the Demographic Health Survey for India. Data from all five rounds is used. The predicted probability of delay in DPT1 was 0.70 (1992-93), which has decreased to 0.31 (2019-21). Delaying the DPT1 vaccine increased chances of not taking the measles vaccine by 35% in 1992-93; it has increased to 72% in 2019-21. Although gender differences in this conditional delay, are marginal, statistically significant rural-urban differences are observed.

Keywords: Children, Adolescents, and Youth, Econometrics , Inequality, Disadvantage and Discrimination

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