Background Kazakhstan has made significant progress in increasing adult population coverage with COVID-19 vaccination, reaching a medium level of coverage (>70%) with primary series vaccines. However, this progress has been significantly uneven across the country’s regions. This study aimed to assess the perceived by the healthcare workers prevalence of myths/vaccination beliefs about COVID-19 vaccines and its association with COVID-19 vaccination coverage in the regions of Kazakhstan.

Methods After the initial qualitative assessment, which included interviews with key experts and representatives of the medical community, the eleven most popular myths/vaccination beliefs about vaccines against COVID-19 were identified. During the quantitative phase in May 2022, 6689 healthcare workers from all 17 regions of Kazakhstan were asked to provide their opinion about the prevalence of each identified myth/belief in their region by filling out an anonymous online questionnaire. Spearman’s rho and Kendall’s tau-b correlation coefficients were estimated to assess the direction and strength of bivariate associations between the proportion of healthcare workers, who reported ‘very high’ or ‘high’ prevalence of particular myths/beliefs in their region, and the proportion of adult (18+) population covered with primary series of COVID-19 vaccines in the region. The coverage of the population by the primary COVID-19 vaccination was assessed by the Ministry of Health and varied between regions from 10.2% to 89.9% during the time of the survey.

Results The identified myths/vaccination beliefs about COVID-19 vaccines were similar to those reported in other countries for which such data have been published and were mainly related to vaccines’ effectiveness and safety. From 36.0% to 65.9% of healthcare workers, depending on the region of Kazakhstan, reported a ‘very high’ or ‘high’ prevalence of myths about COVID-19 vaccines in their region. A higher proportion of healthcare workers reporting in their region a ‘very high’ or ‘high’ prevalence of all COVID-19 vaccines myths combined were associated with lower coverage with primary COVID-19 vaccination in their region (Spearman’s rho = - 0.718, p=0.001; Kendall’s tau-b = - 0.544, p=0.002). The strongest negative statistically significant associations with the COVID-19 primary vaccination coverage were identified for beliefs that: ‘all currently approved vaccines were developed fast, so their safety is questioned’ (rho = - 0.705, p=0.002; tau-b = - 0.539, p=0.003), ‘children do not need to be vaccinated because they develop the mild disease’ (rho = - 0.757, p<0.001; tau-b = - 0.603, p=0.001), and ‘COVID-19 vaccines are generally not effective’ (rho = - 0.696, p=0.002; tau-b = - 0.515, p=0.004).

Conclusion More active information work is required to debunk the most prevalent myths about COVID-19 vaccines among the population of Kazakhstan, which may help reduce differences in COVID-19 vaccination coverage between regions of Kazakhstan.