Reopening of Schools in Bulgaria during COVID-19 Pandemic: 2021 Edition


  • Daniel Stefanov Georgiev Faculty of Dental Medicine, Medical University of Plovdiv, 15A, Vassil Aprilov Blvd., 4002 Plovdiv, Bulgaria.
  • Hristiana Momchilova Batselova Department of Epidemiology and Disaster Medicine, Medical University, Plovdiv, University Hospital “St George,” Plovdiv, Bulgaria.
  • Stanislav Vasilev Kotsev Department of Infectious Diseases, Pazardzhik Multiprofile Hospital for Active Treatment, Pazardzhik, Bulgaria.
  • Tsvetelina Veselinova Velikova Department of Clinical Immunology, University Hospital Lozenetz, Sofia University St. Kliment Ohridski, Sofia, Bulgaria.


“We don’t need no education
We don’t need no thought control
No dark sarcasm in the classroom
Teacher, leave them kids alone
Hey! Teacher! Leave them kids alone!”
Do you remember this song by the legendary band “Pink Floyd”? In the 1970s and 1980s, it could be heard everywhere. And not only. It was seen as a rebellious anthem against being turned into “just another brick in the wall.”


How to cite this article:
Georgiev DS, Batselova HM, Kotsev SV, Velikova TV. Reopening of Schools in Bulgaria during COVID-19 Pandemic: 2021 Edition. Int J Adv Res MicroBiol Immunol 2020; 2(2): 20-21.

Author Biography

Tsvetelina Veselinova Velikova, Department of Clinical Immunology, University Hospital Lozenetz, Sofia University St. Kliment Ohridski, Sofia, Bulgaria.

Tsvetelina Velikova, MD, PhD

LozenetzUniversity Hospital, 1 Kozyak Str., 1407Sofia, Bulgaria

Phone: +359883306049; E-mail:,




Date of birth: 6th August 1985; Place of birth: Sofia, Bulgaria; Citizenship: Bulgarian




03/2011 – 03/2014

Doctor of Philosophy; Medical University of Sofia

PhD thesis: Investigation of immunological parameters for intestinal inflammation in order to establish new markers for diagnosis and follow up of Inflammatory Bowel Disease patients. Advisor: Prof. Iskra Altankova, MD, PhD, DSc

09/2004 - 10/2010

Doctor of Medicine; Medical University of Sofia, Bulgaria



03/2019 – Present

Medical director – Synevo Bulgaria

02/2019 - Present

Medical writer - LeanRank

04/2017 – Present

Specialist in Clinical Immunology –Lozenetz University Hospital; Department of


Clinical Immunology; St. Ivan RilskiUniversity Hospital; Laboratory of Clinical Immunology

07/2015 – 04/2017

Assistant professor –Department of Clinical Laboratory and Clinical Immunology


Medical University of Sofia

07/2015 – Present

Medical editor - Central Medical Library–Medical University of Sofia

12/2011 – 05/2016

Resident in Clinical Immunology; Medical University of Sofia









Google Scholar

Personal blog




English –Professional working proficiency


German, French, Spanish, Mandarin - Elementary




MS Office; WordPress, SPSS v.19; Endnote; Picasa;


Data analysis; writing, editing, proofreading, publishing; scientific projects managing;






  • Methodology of scientific research and medical statistics – University Hospital Tsaritsa Ioanna – ISUL,Sofia (finished 2011)
  • HRP258 Statistics in Medicine – Online-based course on Statistics, Instructor: Dr. Kristin Sainani, Stanford University (finished 2013)
  • Case-Based Introduction to Biostatistics by SCOTT ZEGER, PHD - Free on-line courseof Johns Hopkins University(finished 2013)
  • Writing in the science - Online-based course - Stanford University - Dr. Kristin Sainani (finished 2013)
  • Bioinformatics: Introduction and Methods Web-based on-line course - Peking University - Ge Gao, Liping (finished 2014)
  • Think again: how to reason and argue - Web-based on-line course - Duke University - Walter SinnottArmstrong (finished 2014)
  • How to get published: structuring your article –Elsevier Publishing Campus (finished 2015)
  • How to get published: preparing your manuscript - Elsevier Publishing Campus (finished 2015)
  • How do editors look at your paper. Elsevier Publishing Campus (finished 2015)
  • Publons Academy (currently)




  1. Tsvetelina Velikova, Iliya Karakolev, Zoya Spassova, Dobroslav Kyurkchiev, Iskra Altankova, Spaska Stanilova. Upregulation of mRNA Cytokine Expression Profile in Inflamed Colonic Mucosa of Patients with Inflammatory Bowel Disease. Comptes rendus de l`Academie bulgare des Sciences 2013, vol. 66 (12): 1769-1776. IF 0.198
  2. Dobroslav Kyurkchiev, Emanuil Naydenov, Kalina Tumangelova-Yuzeir, Ekaterina Ivanova-Todorova, Kalina Belemezova, Ivan Bochev, Krasimir Minkin, Milena Mourdjeva, Tsvetelina Velikova, Sevdalin Nachev, Stanimir Kyurkchiev. Cells Isolated from Human Glioblastoma Multiforme Express Progesterone-Induced Blocking Factor (PIBF). Cellular and Molecular Neurobiology. January 2014. IF 2.506
  3. Kalina Tumangelova-Yuzeir, Ekaterina Ivanova-Todorova, Sevdalin Nachev, Tsvetelina Velikova, Emanuil Naydenov, Dobroslav Kyurkchiev. Missing B7 in a part of antigen-presenting cells infiltrating Glioblastoma multiforme. Comptes rendus de l’Academie bulgare des Sciences 2014, Vol 67, No7, pp.1005-1010. IF: 0.284
  4. Tsvetelina Velikova, Ventsislav Nakov, Ralitsa Georgieva, Kalina Toumangelova-Yuzeir, Ekaterina Ivanova-Todorova, Radislav Nakov, Elena Karaivanova, Borislav Vladimirov et Dobroslav Kyurkchiev. Immunomodulating properties of a novel synbiotic on healthy persons. Comptes rendus de l`Academie bulgare des Sciences 2015. Tome 68, No 10:1321-1326. IF: 0.233
  5. Raina Shentova, Tsvetelina Velikova, Christo Zhelev, Emilia Panteleeva, Penka Yaneva, Petio Hadjiiski. Diagnostic value of fecal calprotectin point of care testing in the pediatric practice. Merit research journal of Medicine and Medical Sciences 2016, Vol.4(3):169-172. IF 1.206
  6. Antoaneta Gateva, Yavor Assyov, Tsvetelina Velikova, Zdravko Kamenov. Increased peroxiredoxin 4 levels in patients with prediabetes compared to normal glucose tolerance subjects. Clinical Endocrinology 2016; Vol.85:551-555. IF 3.46
  7. Dobroslav Kyurkchiev, Emanuil Naydenov, Kalina Tumangelova-Yuzeir, Kalina Belemezova, Tsvetelina Velikova, Ekaterina Krassimirova and Ekaterina Ivanova-Todorova. Chapter 2. Stem- Like Adherent Cells Isolated and Cultured from Glioblastoma Multiforme. In: Glioblastoma. Publisher: Avid Science 2016. In press
  8. Tsvetelina Velikova, Dobroslav Kyurkchiev, Ekaterina Ivanova-Todorova, Zoya Spassova, Spaska Stanilova, Iskra Altankova. Cytokines in inflamed mucosa of IBD patients. In: Inflammatory Bowel Disease 2016 (ISBN 978-953-51-4726-8): 71-92.
  9. Radislav Nakov, Tsvetelina Velikova, Ventsislav Nakov, Vanya Gerova, Lyudmila Tankova, Kalina Toumangelova-Yuzeir, Ekaterina Krasimirova, Ekaterina Ivanova-Todorova, Todor Kundurzhiev, Dobroslav Kyurkchiev. Serum Trefoil Factor 3 – a Promising Biomarker in Patients with Inflammatory Bowel Disease. Comptes rendus de l'Academie bulgare des Sciences 2016. Tome 69(12):1669-1674
  10. Gateva, Ts. Velikova, Z. Kamenov. Increased kallistatin levels in patients with  obesity and prediabetes compared to normal glucose tolerance. Endocrine research 2017. (in press) IF 1.5
  11. Yavor Assyov, Tsvetelina Velikova, Zdravko Kamenov. Myostatin and Carbohydrate Disturbances. Endocrine Research 2017;1-8. IF 1.5
  12. Youroukova, D. Dimitrova, А. Valerieva, S. Lesichkova, Ts. Velikova, E. Ivanova-Todorova, K. Tumangelova. Phenotypes determined by cluster analysis in moderate to severe bronchial asthmа. Folia Medica 2017. Vol.59(2)165-173.
  13. Emanuela Tsvetkova Zaharieva, Tsvetelina Veselinova Velikova, Adelina Dimitrova Tsakova, Zdravko Asenov Kamenov. Prevalence of Positive Diabetes Associated Autoantibodies among Type 2 Diabetes and Related Metabolic and Inflammatory Differences in a Sample of the Bulgarian Population. Journal of Diabetes Research 2017. Vol. 2017:1-6.
  14. Tsvetelina Velikova, Dobroslav Kyurkchiev, Zoya Spassova, Iliya Karakolev, Ekaterina Ivanova-Todorova, Iskra Altankova, Spaska Stanilova. Alterations in cytokine gene expression profile in colon mucosa of Inflammatory Bowel Disease patients on different therapeutic regimens. Cytokine 2017. Vol.92(2017):12-19.
  15. MItev, M. Petkova, Ts. Velikova, E. Ivanova-Todorova, R. Shentova, P. Yaneva, R. Ivanova, E. Panteleeva, Chr. Zhelev, D. Kyurkchiev, Z. Spassova, L. Mateva. Prevalence of anti-Saccharomyces cerevisiae antibodies in Bulgarian patients with Crohn`s disease. Comptes rendus de l`Academie bulgare des Sciences 2017. Tome 70(2):289-294.
  16. Emanuela Zaharieva, Tsvetelina Velikova, Adelina Tsakova & Zdravko Kamenov. Reduced soluble Toll-like receptors 2 in type 2 diabetes. Arch Physiology Biochem 2017:1-4.
  17. Krasimirova E, Velikova T, Ivanova-Todorova E, Tumangelova-Yuzeir K, Kalinova D, Boyadzhieva V, Stoilov N, Yoneva T, Rashkov R, Kyurkchiev D.  Treg/Th17 cell balance and phytohaemagglutinin activation of T lymphocytes in peripheral blood of systemic sclerosis patients. World J Exp Med 2017 August 20; 7(3): 58-96.
  18. Tsvetelina Velikova. Problems and perspectives of immunodiagnostics in Bulgaria. J Immunodiagnos. September-2017;1(1):3.
  19. Velikova T. The Mucosal Immunology–Much is Done but the Most is Forthcoming. J Mucosal Immunol Res 2017, 1:2.
  20. Georgiev T, Ivanova M, Kopchev A, Velikova T, Miloshov A, Kurteva E, Yuzeir K, Penkov M, Kabakchieva P, Rashkov R, Stoilov R.Cartilage oligomeric protein, matrix metalloproteinase-3, and Coll2-1 as serum biomarkers in knee osteoarthritis: a cross-sectional study. Rheumatol Int. 2017 Nov 21. doi: 10.1007/s00296-017-3887-y.
  21. Zaharieva E, Kamenov Z, Velikova T, Tsakova A, El-Darawish Y, Okamura H. Interleukin-18 serum level is elevated in type 2 diabetes and latent autoimmune diabetes. Endocr Connect 2017. Vol.7(1):179-185.
  22. Velikova, R. Miladinova, E. Ivanova-Todorova, D. Kyurkchiev, Z. Spasova. Extraintestinal manifestations and intestinal complications in patients with Crohn's disease: associations with some clinico-laboratory findings, immunological markers. Acta medica bulgarica 2018; Vol.XLV(1):16-21.
  24. Tsvetelina V. Velikova, Zoya A. Spassova, Kalina D. Tumangelova-Yuzeir, Ekaterina K. Krasimirova,  Ekaterina   Ivanova-Todorova,  Dobroslav  S.  Kyurkchiev,  and Iskra  P.  Altankova,  “Serological Update on Celiac Disease Diagnostics in Adults.” International  Journal  of  Celiac  Disease,  vol. 6,  no.  1 (2018): 20-25. doi: 10.12691/ijcd-6-1-8.
  25. Velikova T V, Spassova Z A, Milatchkov L M, Panova D G, Ivanova - Todorova E I, et al. Dynamics of Some Routine Immunological Parameters During Anti - TNF Therapy in Patients with Crohn’s Disease, Ann Colorectal Res. Online ahead of Print ;In Press(In Press):e68674. doi: 10.5812/acr.68674.
  26. Velikova T, Shumnalieva R, Tumangelova-Yuzeir K, Kachakova D, Ivanova-Todorova E, Kyurkchiev D, et al. 25-Oh Vitamin D3/D2 Levels in Osteoarthritis and Rheumatoid Arthritis Patients. Ann Chron Dise. 2018; 2(1): 1004.
  27. Tsvetelina Veselinova Velikova, E. Krasimirova, Sn. Lazova, P. Perenovska, A. Valerieva, Dimitrinka MIteva, V. Dimitrov, M. Staevska, D. Kyurkchiev, G. Petrova. MCP-1/CCL2 in a Bulgarian Cohort of Children with Bronchial Asthma and Cystic Fibrosis. Archives of Immunology and Allergy. 2018; 1(1): 1-5.
  28. Kancheva, L., Nikolov, P., Velikova, T., Valkov, I., Nikolov, R., Mateva, L. Soluble CD14 is associated with disease activity and severity in chronic viral hepatitis C and B. C. R. Acad. Bulg. Sci. 2018; 71(6):852-858. DOI: 10.7546/CRABS.2018.06.17
  29. Kalina Tumangelova-Yuzeir, Ekaterina Ivanova-Todorova, Emanuil Naydenov, Tsvetelina Velikova, Ekaterina Krasimirova, Kalina Belemezova, Tihomir Dikov, Marin Penkov, Sevdalin Nachev, Margarita Genova, Dobroslav Kyurkchiev. Cultured Cells Isolated from CNS Indolent B Cell Lymphoma Have Characteristics of Mesenchymal Stem Cells – А Clinical Case and Scientific Research. Int Journal of Hematology-Oncology and stem cells research 2018.;12(3):168-173.  Global IF 0.6
  30. Tsvetelina Velikova. Transplantation in Patients with Autoimmune Liver Diseases. ARC Journal of Hepatology and Gastroenterology. Volume 3, Issue 1, 2018, PP 18-21.
  31. Tsvetelina Velikova and Iskra Altankova. One-step card tests for fecal calprotectin and lactoferrin in patients with inflammatory bowel disease. Int J Biotech Rec Adv. Volume 1, Issue 1, 12-17.
  32. Tsvetelina Velikova, Ekaterina Ivanova-Todorova. Immunoprophylaxis of Respiratory Infections in Childhood. ARC Journal of Immunology and Vaccines 2018;3(1):12-15.
  33. Tsvetelina Velikova. Celiac Disease Vaccination: Expectations and Reality. J Mucosal Immunol Res 2018, 2(1):e105.
  34. Tsvetelina VELIKOVA, Alexander KUKOV, Viktoriya GEORGIEVA, Milena PERUHOVA, Nonka YURUKOVA, Antoaneta MIHOVA, Tsanka MEHANDZHIYSKA – MARINOVA, Gergana MIZGOVA, Velislava TERZIEVA, Galina ZHELEZOVA, Iskra ALTANKOVA, Ludmila IVANOVA; Methods for detection of food intolerance; Recent Advances in Food Science; 2018; 1(3): 106-119
  35. Tsvetelina Velikova, Gergana Taneva, Stanislav Chourchev, Lyudmila Tankova, Borislav Vladimirov. A Case Report of a Patient with Gluten Enteropathy: The Importance of Immunological Markers for Diagnosis and Follow up. ARC Journal of Hepatology and Gastroenterology, Volume 3, Issue 1, 2018, PP 22-24.
  36. Velikova T, Shumnalieva R, Kachakova D, Tumangelova-Yuzeir K, Ivanova-Todorov E, Kyurkchiev D, Monov S. IL-17a – A promising biomarker for disease activity in rheumatoid arthritis patients. Journal of Biomedical Science & Technology [2018] 1(1): 6-20.
  37. Velikova T, Shentovab R, Spassovac Z, et al. Comparative Evaluation of Four Methods for Fecal Calprotectin Testing: One-Step Card Test, A Point of Care Lateral Flow Assay, A Standard and an Automated ELISA. Scimaze Gastroenterol Heppatol 2018;1:101.
  38. Tsvetelina Velikova. Biosimilar drugs for therapy of immunemediated diseases. Biomed Res Rev. 2018 Sep;1(2):106.
  39. Tsvetelina Velikova, Snezhina Lazova, Penka Perenovska, Kalina Tumangelova-Yuzeir, Dimitrinka Miteva, Petar Velikov, Ekaterina Ivanova-Todorova, Dobroslav Kyurkchiev, Guergana Petrova. Th17 Cells in Bulgarian Children with Chronic Obstructive Lung Diseases. Allergologia y immunopatologia, 2018, in press
  40. Velikova TV. Commentary: Therapy strategies regarding cytokines involvement in the pathogenesis of inflammatory bowel disease. Journal of Clinical Investigation and studies 2018, 1(3):1-1. Doi 10.15761/JCIS.1000115
  41. Tsvetelina Velikova, Snezhina Lazova, Penka Perenovska, Kalina Tumangelova-Yuzeir, Dimitrinka Miteva, Petar Velikov, Ekaterina Ivanova-Todorova, Dobroslav Kyurkchiev, Guergana Petrova. Th17 Cells in Bulgarian Children with Chronic Obstructive Lung Diseases. Allergologia y immunopatologia, 2018, in press
  42. Gateva AT, Assyov YS, Velikova T, Kamenov ZA, Higher levels of thyoredoxin interacting protein (TXNIP) in patients with prediabetes compared to obese normoglycemic subjects, Diabetes & Metabolic Syndrome: Clinical Research & Reviews (2018), doi:
  43. Velikova Ts, Altankova I, Reruhova M. Prevalence of Specific IgG to Food Antigens in Bulgarian IBS Patients: A Preliminary Study. M J Nutr.2018; 3(1): 017;1-3.
  44. Velikova Ts, Velikov T, Mihailov G. Higher serum levels of stromelysin 2 (MMP-10) but not matrilysin (MMP-7) in patients with end-stage chronic kidney disease on chroniodialysis. American International Journal of Multidisciplinary Scientific Research 2018; 4(1):17-21.
  45. Ts Velikova. Th17, Vitamin D, and Asthma. Clin Res Immunol 2018;1(1):1-2.
  46. Terzieva V, Velikova Ts, Mihova A, et al. Importance of Regulatory T Cells for the Tolerance Maintaining After Liver Transplantation. M J Immu 2018;2(1): 007, 1-4.
  47. Velikova Ts, Naydenova K, Dimitrov V. Mucosal Inflammation in Allergic Rhinitis and Bronchial Asthma - Two Sides of a Coin. Clin Res Immunol 2018;1(1):1-2.
  48. Tsvetelina Velikova. Immunological aspects of inflammatory bowel disease pathogenesis. Gastroenterol Hepatol Endosc, 2018;3(4):1-3. doi: 10.15761/GHE.1000171
  49. Antoaneta Gateva; Zdravko Kamenov; Vera Karamfilova; Yavor Assyov; Tsvetelina Velikova; Yosif El-Darawish; Haruki Okamura. Higher levels of IL-18 in patients with prediabetes compared to obese normoglycemic controls. ARCHIVES OF PHYSIOLOGY AND BIOCHEMISTRY 2018.
  50. Nakov R, Velikova T, Nakov V, Ianiro G, et al. Serum trefoil factor 3 predicts disease activity in patients with ulcerative colitis. European Review for Medical and Pharmacological Sciences 2019; 23: 788-794.
  51. Kremena Naydenova, Tsvetelina Velikova, Vasil Dimitrov. Interactions of allergic rhinitis and bronchial asthma at mucosal immunology level AIMS Allergy and Immunology, 2019, 3(1): 1-12. doi: 10.3934/Allergy.2019.1.1
  52. Theodora Bolyarova, Raya Grozdanova, Gergana Micheva, Maria Dencheva, Tsvetelina Velikova. EFFECT OF DIODE LASER TREATMENT ON THE LEVEL OF IL-6 IN THE GINGIVAL CREVICULAR FLUID IN PATIENTS WITH CHRONIC PERIODONTITIS. Comptes rendus de l’Acad´emie bulgare des Sciences. Tome 72, No 1, 2019, 130-135. DOI:10.7546/CRABS.2019.01.17
  53. Velikova T, Ivanova-Todorova E, Kancheva L, et al. Serological Differential Diagnosis of Autoimmune Liver Diseases by Line Blot Immunoassay for Parallel Detection of Nine Different Autoantibodies. Clin Exp Gastroenterol Hepatol 2019; 1: 104. doi: 10.31531/edwiser.jcegh.1000104
  54. Tsvetelina V Velikova, Zoya A Spassova, Kalina D Tumangelova-Yuzeir, Ekaterina K Krasimirova, Ekaterina I Ivanova-Todorova, Dobroslav S Kyurkchiev, Iskra P Altankova: Higher serum IL-17A along with anti-tTG antibodies for prediction of refractory celiac disease.
  55. Antoaneta T. Gateva, Tsvetelina V. Velikova, Zdravko A. Kamenov: Peroxiredoxin 4 levels in patients with PCOS and/or obesity. DOI:10.1016/j.jogoh.2019.04.002
  56. Tsvetelina Velikova: Challenges and updates in the management of eosinophilic esophagitis. Przegląd Gastroenterologiczny 04/2019;, DOI:10.5114/pg.2019.84476





  1. Functional repression of autoreactive T cell with antibody therapy in mice and humanized SCID

models of SLE and MS - 2010-2013 - National Fund for Science of Bulgaria

  1. New biomarkers in patients with immunomediated diseases of the gut - 2011-2012 - Medical

University of Sofia, Bulgaria

  1. Assessment of regulatory and effector cytokines of Th17 subpopulation cells in gut mucosa in patients

with IBD - 2012-2013 - Medical University of Sofia, Bulgaria

  1. Contemporary serological methods for diagnosis of gluten enteropathy and optimizing the diagnosis of

dermatitis herpetiformis in elderly patients - 2013-2014 - Medical University of Sofia, Bulgaria

  1. Immunophenotyping of local dendritic cells and NK cells in glioblastoma multiforme - 2013-2014 -

Medical University of Sofia, Bulgaria

  1. Investigation of markers for endothelial dysfunction, activated Th cells, IL-17 and hematopoietic stem

cells - 2013-2014 - Medical University of Sofia, Bulgaria

  1. Th17 lymphocytes and vitamin D in childhood asthma - 2015-2016 - Medical University of Sofia,


  1. New diagnostic and prognostic biomarkers for rheumatoid arthritis - 2015-2016 - Medical University of

Sofia, Bulgaria

  1. Optimizing the immunological diagnostics of different forms of progressive systemic sclerosis by

performing a broad panel of autoantibodies investigation - 2015-2016 - Medical University of Sofia,


  1. Phenotyping of bronchial asthma in adults - 2015-2016 - Medical University of Sofia, Bulgaria
  2. Polycystic ovarian syndrome and cardiovascular risk - 2016 - 2017 - Medical University of Sofia,


  1. Neurologic, vascular and biochemical factors in evolution of diabetic foot - 2016 - 2017 - Medical

University of Sofia, Bulgaria

  1. Th17 cells and cytokines in multiple sclerosis patients – 2017-2018, Medical University of Sofia
  2. Specific IgG to food antigens in IBS patients – Sofia University – 2017-2018
  3. Treg cells and soluable CD30 in patients with solid organ transplantation - Sofia University – 2017-2018