Covid-19 Research

Research Article

Risk Index for Measles outbreak in Bulgaria for the period 2001 - 2024

Journal of Biomedical Research & Environmental Sciences article abstract with citation details, DOI, publication dates, subject areas, full text links, and references.

View DOI Submit Manuscript

Article Details

Publication record, authors, dates, abstract, and full text access.

Open Access
Article Type Research Article
Subject Medicine Group
OCLC JBRES Record
Ognyan Kounchev, Georgi Simeonov, Hristiana Batselova, Trifon Valkov, Radka Argirova* and G. Boyadzhiev
Issue: Volume6-Issue2
Pages: 131-138
Received: 2025-01-21
Accepted: 2025-02-13
Published: 2025-02-14

Abstract

Background/Objectives: Measles is a highly contagious, vaccine-preventable infectious disease. According to the ECDC report “Measles on the rise in the EU/EEA: considerations for public health response” [1], urgent action is required to address the increasing spread of measles and insufficient vaccination coverage across the EU. This study aims to develop a mathematical model for assessing the risk of measles outbreak/s and virus transmission in Bulgaria from 2001 to 2024. To achieve this, a Risk Index (RI) for measles outbreak was calculated based on age-structured immunization coverage and demographic trends.

Methods: Data on immunization coverage and demographic dynamics in Bulgaria were collected from 1971onward, encompassing a 50-year period. Census records dating back to 1970 were used to obtain age-structured demographic data. Established mathematical interpolation and extrapolation techniques were applied to estimate annual immunization coverage and demographic parameters. The Risk Index was calculated as a ratio of susceptible individuals to the total population.

Results: The Risk Index for measles outbreaks in Bulgaria was computed over a 50-year period. The key finding of this study is the definition and calculation of the Risk index, which reveals a concerning increase after 2015, with particularly alarming values projected for 2023 and beyond.

Conclusions: The high incidence of measles and its frequent complications pose a significant burden on healthcare systems, increasing hospitalizations and complicating prevention efforts, particularly among vulnerable populations. The proposed model provides valuable insight for health authorities to predict, prevent and localize outbreaks ensuring adequate healthcare preparedness, including sufficient medical resources and technical capacity. Additionally, the model can be adapted to assess the risk of outbreaks for other vaccine-preventable infectious diseases, such as influenza, pertussis, and, varicella, making it a useful tool for epidemic forecasting and prevention.

FullText HTML FullText PDF DOI: 10.37871/jbres2065 Crossmark

Certificate of Publication

Certificate of Publication

Copyright

© 2025 Kounchev O, et al. Distributed under Creative Commons CC-BY 4.0 Creative CommonsAttribution

How to cite this article

Kounchev O, Simeonov G, Batselova H, Valkov T, Argirova R, Boyadzhiev G. Risk Index for Measles outbreak in Bulgaria for the period 2001 – 2024. J Biomed Res Environ Sci. 2025 Feb 14; 6(1): 131-138. doi: 10.37871/jbres2065, Article ID: JBRES2065, Available at: https://www.jelsciences.com/articles/jbres2065.pdf

Subject area(s)

Public HealthEpidemiology

References

  1. European centre for disease prevention and control. Measles on the rise in the EU/EEA: considerations for public health response. Stockholm: ECDC; 2024.
  2. Moss WJ, Griffin DE. Global measles elimination. Nat Rev Microbiol. 2006 Dec;4(12):900-8. doi: 10.1038/nrmicro1550. Epub 2006 Nov 6. PMID: 17088933; PMCID: PMC7097605.
  3. Panum P. Observations made during the epidemic of measles on the Faroe Islands in the year 1846. Med Classics. 1938;3:829-886. doi: 10.1001/jama.1940.02810460079037.
  4. Behrens L, Cherry JD, Heininger U; Swiss Measles Immune Amnesia Study Group. The Susceptibility to Other Infectious Diseases Following Measles During a Three Year Observation Period in Switzerland. Pediatr Infect Dis J. 2020 Jun;39(6):478-482. doi: 10.1097/INF.0000000000002599. PMID: 32084116.
  5. Miller KD, Matullo CM, Milora KA, Williams RM, O'Regan KJ, Rall GF. Immune-Mediated Control of a Dormant Neurotropic RNA Virus Infection. J Virol. 2019 Aug 28;93(18):e00241-19. doi: 10.1128/JVI.00241-19. PMID: 31270232; PMCID: PMC6714802.
  6. World Health Organization. Measles.
  7. Guerra FM, Bolotin S, Lim G, Heffernan J, Deeks SL, Li Y, Crowcroft NS. The basic reproduction number (R0) of measles: a systematic review. Lancet Infect Dis. 2017 Dec;17(12):e420-e428. doi: 10.1016/S1473-3099(17)30307-9. Epub 2017 Jul 27. PMID: 28757186.
  8. University of oxford. MMR Vaccine.
  9. Komitova R, Kevorkyan A, Boykinova O, Krumova S, Atanasova M, Raycheva R, Stoilova Y, Kunchev A. Difficulties in achieving and maintaining the goal of measles elimination in Bulgaria. Rev Epidemiol Sante Publique. 2019 May;67(3):155-162. doi: 10.1016/j.respe.2019.01.120. Epub 2019 Feb 23. PMID: 30803747.
  10. ECDC: Vaccine schedule by countries.
  11. Ministry of health, Bulgaria. The national programme for elimination of measles and rubella.
  12. https://www.ncipd.org/images/UserFiles/File/Epidemiologia/ANALYSIS%20OF%20IMMUNOPROPHYLAXIS%20IN%20B...
  13. WHO. Immunization dashboard.
  14. WHO. Measles and rubella elimination country profile of Bulgaria.
  15. de Boor CR. A Practical guide to splines. 2nd ed. Springer-Verlag; 1978. doi: 10.2307/2006241.
  16. Marinova L, Kojouharova M, Mihneva Z. Measles epidemic in Bulgaria in 2009-2010: Reasons and lessons learnt. Pediatria. 2011;1:38-43.
  17. Muscat M, Marinova L, Mankertz A, Gatcheva N, Mihneva Z, Santibanez S, Kunchev A, Filipova R, Kojouharova M. The measles outbreak in Bulgaria, 2009-2011: An epidemiological assessment and lessons learnt. Euro Surveill. 2016;21(9):30152. doi: 10.2807/1560-7917.ES.2016.21.9.30152. PMID: 26967661.
  18. Vaccine scheduler. Bulgaria: Recommended vaccinations.
  19. Vatev N, Stoycheva M, Petrov A, Reemergence of measles in Bulgaria: A large outbreak in Plovdiv, 2010. 2011;15(6). doi: 10.1590/S1413-86702011000600021.
  20. Gidding HF, Quinn HE, Hueston L, Dwyer DE, McIntyre PB. Declining measles antibodies in the era of elimination: Australia's experience. Vaccine. 2018 Jan 25;36(4):507-513. doi: 10.1016/j.vaccine.2017.12.002. Epub 2017 Dec 18. PMID: 29269156.
  21. Naniche D, Garenne M, Rae C, Manchester M, Buchta R, Brodine SK, Oldstone MB. Decrease in measles virus-specific CD4 T cell memory in vaccinated subjects. J Infect Dis. 2004 Oct 15;190(8):1387-95. doi: 10.1086/424571. Epub 2004 Sep 8. PMID: 15378430.
  22. Pedro Plans-Rubió. Measles vaccination coverage and anti-measles herd immunity levels in the World and WHO regions worsened from 2019 to 2023. Vaccines. 2025;13(2):157. doi: 10.3390/vaccines13020157.
  23. WHO. Global vaccine action plan.
  24. WHO/UNICEF. Immunization agenda 2030.
  25. WHO. Centralized Information System for Infectious Diseases (CISID). Measles-number of cases. 2015-2023.
  26. WHO. Centralized Information System for Infectious Diseases (CISID). Measles-number of hospitalizations. 2023.
  27. WHO. Centralized Information System for Infectious Diseases (CISID). Measles-number of deaths. 2023.
Publish with JBRES — Peer-reviewed, multidisciplinary Open Access with rapid review, DOI, and global visibility.
Double-Blind CrossRef DOI Discoverable
Submit Manuscript Membership