DISTRICT-LEVEL VARIATION IN COVID-19 VAC-CINATION RATES AND AVAILABILITY OF VACCI-NATION SERVICES IN BULGARIA

Purpose: Since early 2022, the COVID-19 vaccina-tion rate in Bulgaria has remained low, with large regional differences. This study examines the association between the availability of vaccination sites and the number of ad-ministered doses, and the extent to which district-level vari-ation is attributable to differences in vaccination services provision.Materials and Methods: Data on COVID-19 vaccine doses administered by districts were used. This data set was combined with district-level information on available vac-cination sites, such as general practitioners and temporary vaccination points. The district-level differences in vacci-nation coverage and service provision were illustrated through country heat maps, and the association between the variables was explored using two linear regression models.Results: According to the first regression model, the number of general practitioners and temporary vaccination points accounted for only 3.8% of the district-level varia-tion in administrated doses. As covariates in the second model, sociodemographic and economic data were in-cluded. The combined influence of these factors explained 42.2% of the variance across districts. According to the findings, the average annual gross wage is a significant de-terminant of the district-level differences in the number of administrated doses.Conclusion: There is no statistically significant as-sociation between administered doses and vaccination sites by districts, which does not correspond to the findings of other international studies. District-level variation in vac-cination rates is associated with some sociodemographic and economic differences. The paucity of district-level data impedes further analyses of the vaccine coverage differ-ences and their underlying determinants.