Introduction:
With an impressive track record in expanding childhood immunization and an inclination to adopt digitalization in healthcare service delivery, Expanded Program on Immunization (EPI) Bangladesh piloted the e-Tracker intervention in Moulavibazar district and Dhaka South City Corporation (Zone-5) from 2019 till the end of 2021.

Objective:
We analyzed the digitalized e-Tracker data intending to calculate vaccination coverages, dose timeliness, and dropout rates for children under one year of age from Pre-COVID and during-COVID era to aid with informed decision-making by the policymakers.

Method:
With help from Health Management Information System (HMIS) and UNICEF Bangladesh, we retrieved e-Tracker data for infants born between January 1, 2019, and December 31, 2021. Childhood vaccination coverage and dropout rates were determined using a Traditional approach traditionally used by WHO and a Conditional technique with a modified denominator. Using a multivariate logistic regression model, we examined the relationship between vaccination rates and birth cohorts, mother education, and location.

Result:
The conditional estimation yielded a lower full vaccination coverage (68.7%) than the national (from aggregated data, 89.0%) and global coverage (81.0%). Coverage and dropout rates increased more during the ‘during-COVID’ era than in the ‘pre-COVID’ period. However, dropouts were estimated lower in the ‘conditional method.’ The average age (in months) for getting BCG was higher in Moulavibazar (~2.5 months) than that in Dhaka (~1.4 months). All child birth-cohorts from ‘the during-COVID’ era had about a 30% lower chance of getting fully vaccinated than those from the ‘pre-COVID’ era.

Conclusion:
Age-cohort-specific studies showed a reduction in coverage estimates before and after COVID, but e-Tracker didnt have enough data to draw additional conclusions. The server only stored the childs gender, the caregiver’s monthly salary, and the mothers education. It didnt track the dropout factors or if families departed pilot regions. Future updates and system expansion should help.