The dual economic impact of COVID-19 vaccine hesitancy - Bulgaria's conundrum case

The dual economic impact of COVID-19 vaccine hesitancy - Bulgaria’s conundrum case Svetlin Georgiev1, Borislav Borissov1, Alexandrina Vodenicharova1, Antoniya Yanakieva1 1 Medical University of Sofia, Sofia, Bulgaria Corresponding author: Svetlin Georgiev ([email protected]m) Received 29 September 2025♦ Accepted 5 November 2025♦ Published 27 November 2025 Citation: Georgiev S, Borissov B, Vodenicharova A, Yanakieva A (2025) The dual economic impact of COVID-19 vaccine hesitancy - Bulgaria’s conundrum case. Pharmacia 72: 1–4. https://doi.org/10.3897/pharmacia.72.e173509 Abstract Bulgaria is assumed to be the country with the lowest COVID-19 vaccination coverage in the EU. The present study aims to highlight the economic impact of vaccine hesitancy. The period analyzed is from 1 January 2021 to 31 December 2021, examining hospitalization costs for COVID-19 patients, vaccine application costs, and vaccine type and dose administered. Results demonstrate a net impact of BGN 97 686 089 (€49 946 104) if 30% of the eligible population had been vaccinated and BGN 146 529 133 (€74 919 156) if a 45% rate had been achieved. In addition, 5.1 million unused doses were scrapped—more than those administered. The public health impact of vaccine hesitancy in Bulgaria led to a preventable medical crisis, substantial economic losses due to avoidable hospitalizations, and significant additional costs associated with the destruction of unused vaccines. Keywords Bulgaria, COVID-19, vaccination coverage, European Union Introduction By the end of 2021, the EU had signed €71 billion worth of contracts, securing up to 4.6 billion doses of COVID-19 vaccines (EU Vaccines Strategy Website). The Commission took over the vaccine procurement initiative for the entire EU to prevent wasteful competition for scarce vaccines between member states and to protect smaller ones from being charged higher prices or even losing out. The EU’s centralized procurement strategy has received criticism (Gandjour 2022) but succeeded in creating a diversified portfolio of vaccine candidates and in procuring sufficient doses of COVID-19 vaccines during the pandemic. In some countries in Eastern Europe, notably Bulgaria, nevertheless, although there are many options (Grigorov 2013), vaccine coverage remained much lower than in Central and Western European countries. By November 2021, only 23.04% of people were fully vaccinated, and the country is among those with the highest COVID-19 mortality rate even though it had an ample supply of vaccines. Ninety-four percent of deaths were of unvaccinated individuals (Fan 2022). A major concern that limited the impact of vaccination remained vaccine hesitancy. Underlying reasons for vaccine hesitancy were rooted in a complex interaction between lack of trust in government and health authorities, coupled with vast and persistent misinformation in social media campaigns (Larson and Broniatowski 2021; Fan et al. 2022). Various economic evaluations have estimated the cost-effectiveness of vaccination, with very favorable results (Hogan et al. 2021; Mesa et al. 2022), suggesting that vaccines against COVID-19 can significantly reduce healthcare costs (Debrabant 2021; Kohli 2021; Padula 2021; Shaker 2021; López 2022; Wang 2022; Hoxha 2023). Copyright Georgiev S et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Pharmacia 72: 1–4 DOI 10.3897/pharmacia.72.e173509 Short Communication Georgiev S et al.: The dual economic impact of COVID 19 vaccine hesitancy2 In the present study, we aim to understand the likely economic impact of vaccine hesitancy on the control of the pandemic in Bulgaria. Materials and methods The period analyzed is from 1 January 2021 to 31 December 2021. By July 2022, the Ministry of Health (MoH) and the National Health Insurance Fund (NHIF) provided official written information under request pursuant to the Access to Public Information Act (adopted 2000, last amended 2019), Art. 2, para. 1 and 2 (National Health Insurance Fund Letter in response). Data included in the calculations are derived from those two sources and include hospitalization costs for COVID-19 patients, vaccine application costs, and vaccine type and dose administered. Mortality rates for vaccinated and nonvaccinated patients were derived from the official register of the MoH. Costs for the booster dose are not included in the analysis. Data were analyzed with the TreeAgePro Healthcare v2023 R1.0 budget impact application. Results From 1 January 2021 to 31 December 2021, 3 695 586 doses from four vaccine types were administered (Table 1). The MoH spent BGN 46 474 576 (€23 762 073) for vaccine acquisition, while the NHIF paid BGN 31 582 890 (€15 148 075), or BGN 10 (€5.12) per dose. A total of 537 297 doses appear to not be charged to the NHIF. For 6 195 595 eligible people (age >16 or 18; National Statistical Institute, www.nsi.bg), the coverage is 36.87%. During the period, the NHIF paid for 210 485 hospitalizations (including re-hospitalizations) of COVID-19 patients, resulting in BGN 331 294 919 (€169 388 402) in costs, or an average of BGN 1 573.959 (€804.78) per patient. From 155 044 hospital admissions, 5.10% (7910) of patients were vaccinated with at least one dose. A total of 23 375 people died from COVID-19 in 2021, and 3.456% (800) were vaccinated with at least one dose. These data suggest that fewer than a total of 4.6 million doses have been administered in Bulgaria as official figures show, and fewer than 2 million people have completed a two-shot vaccination course, while far fewer than 1 million have received a booster dose. A quick budget impact analysis was performed to assess the net impact in the 30% (Table 2) vaccine uptake scenario versus a higher rate of 45% (Table 3). Results demonstrate a net impact of BGN 97 686 089 (€49 946 104) if 30% of the eligible population had been vaccinated and BGN 146 529 133 (€74 919 156) if a 45% rate had been achieved. Standard of care is defined as the hospitalization cost covered by the NHIF, whereas the cost per vaccine is calculated at an average of BGN 17 per dose and BGN 10 per application, totaling BGN 27 (€13.8) per jab. Table 2. Budget scenario—standard of care only (30% vaccine uptake). Patients receiving standard of care 2021 210 485 New budget scenario—gradual uptake of new treatment New treatment uptake % 30% Patients receiving standard of care 2021 147 339.5 Patients receiving new treatment 2021 63 145.5 Total treatment costs per year Standard of care BGN 1 574 New treatment BGN 27 Budget impact calculations Current budget scenario—standard of care only 2021 331 303 390 New budget scenario—gradual uptake of new treatment Cost for patients receiving standard of care 2021 231 912 373 Cost for patients receiving new treatment 2021 1 704 929 Cost sum for patients receiving standard of care or new treatment 2021 233 617 302 Net budget impact (97 686 089) Table 3. Budget scenario—standard of care only (45% vaccine uptake). Patients receiving standard of care 2021 210 485 New budget scenario—gradual uptake of new treatment New treatment uptake % 45% Patients receiving standard of care 2021 115 766.75 Patients receiving new treatment 2021 94 718.25 Total treatment costs per year Standard of care BGN 1 574 New treatment BGN 27 Budget impact calculations Current budget scenario—standard of care only 2021 331 303 390 New budget scenario—gradual uptake of new treatment Cost for patients receiving standard of care 2021 182 216 865 Cost for patients receiving new treatment 2021 2 557 393 Cost sum for patients receiving standard of care or new treatment 2021 184 774 257 Net budget impact (146 529 133) Table 1. Number of administered COVID-19 vaccine doses and corresponding application costs in BGN. Vaccine No of doses Application cost in BGN Pfizer 2 337 923 10 Astra Zeneca 478 261 10 J&J 465 569 10* Moderna 413 833 10 Total 3 695 58631 582 890 *Single dose, i.e., one application cost. Pharmacia 72: 1–4 3 Discussion There have been approximately 1.3 million confirmed cases of COVID-19 in Bulgaria amid the pandemic and a death toll of 38 211, with 23 375 occurring in 2021 alone. Although the coverage may be higher than expected—up to 36.87%—the low vaccination rate resulted in massive opportunity costs and high hospitalization and mortality rates. In addition, on 6 March 2023, Bulgarian health authorities announced that 2.8 million expired COVID-19 doses would be destroyed that year, following another 2.3 million doses that had already been scrapped in the country with the lowest vaccination rate in the EU. Bulgaria destroys more anti-COVID vaccines than it has administered. The public health impact of vaccine hesitancy, driven mainly by a systematic and hostile social media environment, resulted in a potentially preventable medical crisis accompanied by meaningful budget losses from avoidable hospitalizations and further fueled by substantial costs associated with the destruction of unused vaccines. Conclusion The present analysis demonstrates that vaccine hesitancy in Bulgaria has led to both substantial public health and economic repercussions. Despite sufficient vaccine availability and evidence supporting cost-effectiveness, Bulgaria’s low vaccination coverage in 2021 (36.87%) resulted in preventable hospitalizations, deaths, and significant financial losses. If vaccination uptake had reached 40–45% of the eligible population, the healthcare system could have saved between BGN 97.7 million (€49.9 million) and BGN 146.5 million (€74.9 million) in hospitalization costs. Furthermore, the misuse and later destruction of more than 5 million unused vaccine doses underscores inefficient resource utilization and deep systemic mistrust in public health policies. In conclusion, the Bulgarian case exemplifies the dual economic burden of vaccine hesitancy—direct medical expenses generated from preventable illness and indirect fiscal losses from wasted vaccines—highlighting the urgent need for stronger public trust, strategic communication, and evidence-based policy interventions to counteract misinformation and enhance vaccination uptake. Additional information Conflict of interest The authors have declared that no competing interests exist. Ethical statements The authors declared that no clinical trials were used in the present study. The authors declared that no experiments on humans or human tissues were performed for the present study. The authors declared that no informed consent was obtained from the humans, donors or donors’ representatives participating in the study. The authors declared that no experiments on animals were performed for the present study. The authors declared that no commercially available immortalised human and animal cell lines were used in the present study. Use of AI No use of AI was reported. Funding No funding was reported. Author contributions All authors have contributed equally. Author ORCIDs Svetlin Georgiev https://orcid.org/0000-0001-9320-8860 Borislav Borissov https://orcid.org/0000-0003-1711-0284 Alexandrina Vodenicharova https://orcid.org/0000-00023703-5253 Antoniya Yanakieva https://orcid.org/0000-0001-6418-2788 Data availability All of the data that support the findings of this study are available in the main text. References Debrabant K, Grønbæk L, Kronborg C (2021) The cost-effectiveness of a COVID-19 vaccine in a Danish context. Clin. 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