STATUS OF ANTIBIOTIC RESISTANCE

Acute respiratory infections are highly prevalent in Bulgaria.


CHAPTER OVERVIEW

APUA Bulgaria was established in 1998 and is comprised of 105 members. Members are involved in different aspects of Antimicrobial Chemotherapy, including national and international societies like the Bulgarian Society for Medical Microbiology (BSMM), the Bulgarian Association of Microbiologists (BAM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), European Society of Chemotherapy (and) Infectious Diseases (ESCiD), International Society of Chemotherapy (ISC) and others.

Chapter Objectives and Priorities:
Since its foundation, the Chapter has two main goals:

  • Containment of Antimicrobial Resistance
  • Rational Antibiotic Policies/Antibiotic stewardship.

CHAPTER ACTIVITIES

 
 
 

12th National congress on Clinical Microbiology and Infection

  • Work on proficiency in identification of the etiology of infections in patients
  • Control of quality of antimicrobial susceptibility testing
  • Antimicrobial Resistance Surveillance – both Institutional and National
  • Measurement of antibiotic consumption
  • Expertise on antibiotic therapy of patients – advice on selection of the most appropriate antibiotic/antibiotic regimen to the patient; clinical rounds, visitations at hospitals; control of management of infected patients with an emphasis on those with severe, systemic, life-threatening infections, and/or with multiple drug resistant organisms
  • Organization and control of hospital antibiotic policies – creation of multi-disciplinary antibiotic teams, development of lists of essential antibiotics, setting restriction levels on prescribing, development of clinical guidelines for empiric antibiotic therapy, clinical guidelines for therapy of infections by anatomic sites, and guidelines for Antimicrobial Prophylaxis in Surgery
  • Education. The problems of Antimicrobial Resistance and Rational Antibiotic policies are introduced both in under-graduate and post-graduate education of students in medicine, dentistry and pharmacy. Medical universities in the country and the National Centre for Infectious and Parasitic Diseases (NCIPB) perform regular courses with expert lecturers. Other educational forums are seminars, workshops, scientific conferences and printed materials. Consumers’ education is performed with the help of mass-media and includes discussions on TV, radio, and printed information in newspapers and journals.
  • Research. Different aspects of prevention and diagnosis of infections and infecting agents, including newly emerging and re-emerging, are subjects of investigations. Mechanisms and epidemiology of antibiotic resistance are very exciting. Other researchers study the action of antibiotics in patients, work on improving antibiotic prescribing, or are involved in biosecurity issues. The results are being published or presented at national and international scientific conferences and sometimes, representatives from the chapter are invited lecturers.

Among APUA Bulgaria’s greatest achievements are:

18 November 2013 – the European antibiotic day

  • The participation in an Expert Committee with the Ministry of Health (2000-2003) to create National Antimicrobial Resistance Surveillance and Rational Antibiotic Use Policies. The first part of this task resulted in the foundation of the reference laboratory on antimicrobial resistance and its work on the national surveillance program BulSTAR (www.bam-bg.net)*.
  • The conference, “Rational Antibiotic Policy,” help on 3-5 June, 2005 in Sofia, jointly co-organized with BSMM, BAM and ESGAP (ESCMID)
  • A project on resistance surveillance, supported by the APUA small grants program
  • The international cooperation: projects ARPAC, EARSS, ESAC (ESCMID) and the work in the ESCMID Study Groups: ESGAP, ESGARS and others 
  • The Inquiry on Antibiotics and Antibiotic policies, performed on the occasion of the second “Antibiotic Day” (ECDC, WHO) on 18 November, 2009 among patients and medical personnel. View Poster #1 and Poster #2 from this event.

2005 "Rational Antibiotic Policies" conference held in Sofia
 

APUA Bulgaria is interested in taking part in a mutual project on the problems of antibiotic resistance (e.g. ESBL-producers, MDR - GNNF, MRSA) or antibiotic policy (e.g. in surgery, in BSI, in UTI, in ICU: an antibiotic audit of prescriptions, antibiotic consumption, adherence to guidelines etc) with other countries that have similar problems.

Dr. Rossitza Vatcheva-Dobrevska (Head of the National Reference Centre for Healthcare-Associated Infections) and Dr. Emma Keuleyan (APUA-Bulgaria President) gave an overview of infection control measures being implemented in Bulgaria. The incidence of healthcare-associated infections (HAIs) dropped from 12.7% in 2007 to 11.2% in 2008, and 10.2% in 2009. Over the past five years, the recorded incidence decreased by approximately 3%. From 1999 to 2009, the incidence decreased by approximately 10% (21.1% to 10.2%). In a national point prevalence survey conducted in 2006 among 23 acute-care hospitals in Bulgaria, the overall prevalence rate of HAI was 2.43%. Highest prevalence rates were found in intensive care units (15.2%) and surgical wards (4.1%). Of all HAIs, the most common types were surgical site infections (43.18%), pneumonia (27.27%), urinary tract infections (20.45%), and primary bloodstream infection (9.09%). Dr. Keuleyan cites lack of resources within current practice to handle AMR within hospitals.


APUA-Bulgaria shares national responsibility with the Ministry of Health, the National Center for Infectious and Parasitic Diseases (NCIP), the National Reference Center for Healthcare-Associated Infections (NRC-HAI), and the National Centre for Public Health and Information (NCPHI) for infection control activities. Bulgaria has also participated in a series of ECDC surveys of HAIs, such as the European Clostridium difficile infection surveillance network project (ECDIS-net), as well as a national campaign for hand hygiene. The hand hygiene campaign included an evaluation of existing resources and standards within hospitals as well as a survey of patient knowledge. For World Health Day on April 7, 2011, APUA-Bulgaria collaborated with the Bulgarian Association of Microbiologists and the Medical Institute of the Ministry of the Interior to produce a poster about broad-spectrum beta-lactamases (ESBLS).


Over the next few years, Bulgaria will focus on implementation of the Medical HAI Standard, the Program for HAI Prevention and Control, and the control of antimicrobial resistance. Goals include harmonization of national practical standards for infection prevention and control with European standards. Practical implementation in health care facilities will include measures for improving patient and personnel safety, containment of HAIs and AMR, and a better understanding of the scope and consequences of HAIs in the medical community and society. Future activities include participation in the ECDC European Point Prevalence Survey of HAI and Antimicrobial Use in European Acute Care Hospitals for 2011-2012, and the introduction of the new ECDC protocols for active HAI surveillance in hospitals to allow participation in the ECDC HAI-NET.


CHAPTER LEADERSHIP

Prof. Encho Savov, MD, PhD, DSc; President
Prof. Emma Keuleyan, MD, PhD; co-ordinator
Assoc.-Prof. Kalinka Bojkova, MD, PhD; Dept Microbiology and Virology, Medical University, Varna
Prof. Marianna Murdjeva, MD, DSi; Head, Dept Microbiology and Immunology, Medical University, Plovdiv, Vice-Rector on Scientific Affairs
Prof. Todor Kantardjiev, MD, DSci; Director, National Center for Infectious and Parasitic Diseases, Sofia, National expert in Microbiology, President, Bulgarian Association of Microbiologists
Assoc.-Prof. Grozdanka Lazarova, MD, PhD; Head, Dept Microbiology, Thracian Medical University, Stara Zagora
Assoc.-Prof. Boyka Markova, MD, PhD; Head, Clinical Microbiology Lab, Sinevo, Sofia
Assoc.-Prof. Roumyana Markovska, MD, PhD; Head, Antimicrobial Resistance Lab, Chair of Medical Microbiology, Medical University, Sofia
Maria Popova, MD, PhD; Head, Dept Control of Drugs Usage, Bulgarian Drug Agency, Sofia
Prof. Mariya Sredkova, MD, DSci; Head, Dept Microbiology, Medical University, Pleven
Assoc.-Prof. Rossitza Vacheva-Dobrevsky, MD, PhD; Head, Dept Microbiology, “Queen Ioanna” University Hospital, Sofia

For more information on Bulgaria, see APUA Clinical Newsletter Vol. 30. No. 2.


LIST OF RECENT APUA-Bulgaria PUBLICATIONS ON ANTIMICROBIAL RESISTANCE
Scientific publications in International journals

  • Alexandrova А, Setchanova L, Sredkova M, Haydoushka I, Markova B, Proevska U, Bojkova K, Mitov I. MLSB genotype is predominant molecular genetic mechanism among erythromycin-resistant Streptococcus pneumoniae for the period: 2006-2008. Journal of IMAB Annual Proceeding (Scientific Papers) 2009, Book 1, part Medicine, p.36-38. http://www.journal-imab-bg.org/
  • Adriaenssens N, Coenen S, Muller A, Vankerckhoven V, Goossens H; ESAC Project Group incl. B.Markova. European Surveillance of Antimicrobial Consumption (ESAC): outpatient systemic antimycotic and antifungal use in Europe. J Antimicrob Chemother. 2010 Apr; 65 (4):769-74.
  • Adriaenssens N, Coenen S, Versporten A, Muller A, Minalu G, Faes C, Vankerckhoven V, Aerts M, Hens N, Molenberghs G, Goossens H on behalf of the ESAC Project Group incl. B.Markova. European Surveillance of Antimicrobial Consumption 1 (ESAC): Outpatient antibiotic use in Europe (1997-2009). J Antimicrob Chemother 2011, 66 Suppl 6; vi3-vi12  
  • Adriaenssens N, Coenen S, Versporten A, Muller A, Vankerckhoven V, Goossens H on behalf of the ESAC Project Group incl. B.Markova. European Surveillance of Antimicrobial Consumption 1 (ESAC): Quality appraisal of antibiotic use in Europe. J Antimicrob Chemother 2011, 66 Suppl 6; vi71-vi77
  • Adriaenssens N, Coenen S, Versporten A, Muller A, Minalu G, Faes C, Vankerckhoven V, Aerts M, Hens N, Molenberghs G, Goossens H on behalf of the ESAC Project Group incl. B.Markova. European Surveillance of Antimicrobial Consumption 1 (ESAC): Outpatient macrolide, lincosamide and streptogramin (MLS) use in Europe (1997-2009). J Antimicrob Chemother 2011, 66 Suppl 6; vi37-vi45
  • Adriaenssens N, Coenen S, Versporten A, Muller A, Minalu G, Faes C, Vankerckhoven V, Aerts M, Hens N, Molenberghs G, Goossens H on behalf of the ESAC Project Group incl. B.Markova. European surveillance of antimicrobial consumption (ESAC): Outpatient quinolone use in Europe (1997-2009). J Antimicrob Chemother 2011, 66 Suppl 6; vi47-vi56  
  • Boyanova, L., Ilieva, J., Gergova, G., Spassova, Z., Nikolov, R., Davidkov, L., Evstatiev, I., Kamburov, V., Katsarov, N., Mitov, I. Evaluation of clinical and socio-demographic risk factors for antibacterial resistance of Helicobacter pylori in Bulgaria. J. Med. Microbiol. 2009; 58(1):94-100. (IF2010-2,380)
  • Boyanova L, Setchanova L, Gergova G, Kostianev T, Yordanov D, Popova C, Kotsilkov K, Mitov I. Microbiological diagnosis of the severe chronic periodontitis. Journal of IMAB- Annual Proceeding (Scientific Papers) 2009; Book 2(Part Dentistry (Oral and Dental Medicine): 89-94. http://www.journal-imab-bg.org/en/vol-15_book-2.htm
  • Boyanova L., Stephanova-Kondratenko M., Mitov I. Anti-Helicobacter pylori activity of Lactobacillus delbrueckii subsp. bulgaricus strains: preliminary report. Lett Appl Microbiol. 2009; 48 (5): 579-584. (IF2009-1,647)
  • Boyanova L. Prevalence of multidrug-resistant Helicobacter pylori in Bulgaria. J. Med. Microbiol. 2009; 58 (Pt 7): 930-935. (IF2010-2,380)
  • Boyanova L, Mitov I. Geographic map and evolution of primary Helicobacter pylori resistance to antibacterial agents. Expert Rev Anti Infect Ther. 2010; 8(1):59-70. (IF2011-3,090)
  • Boyanova L, Nikolov R, Gergova G, Evstatiev I, Lazarova E, Kamburov V, Panteleeva E, Spasova Z, Mitov I. Two-decade trends in primary H. pylori resistance to antibiotics in Bulgaria. Diagn Microbiol Infect Dis. 2010; 67: 319-326. (IF2011-2,528)
  • Boyanova L, Yordanov D, Gergova G, Markovska R, Mitov I. Association of iceA and babA genotypes in Helicobacter pylori strains with patient and strain characteristics. Antonie Van Leeuwenhoek. 2010; 98 (3):343-350. (IF2011-2,091)
  • Boyanova L, Kolarov R, Gergova G, Dimitrova L, Mitov I. Trends in antibiotic resistance in Prevotella species from patients of the University Hospital of Maxillofacial Surgery, Sofia, Bulgaria, in 2003-2009. Anaerobe. 2010; 16(5): 489-492. (IF2011-2,409)
  • Boyanova L, Ilieva J, Gergova G, Davidkov L, Spassova Z, Kamburov V, Katsarov N, Mitov I. Numerous risk factors for Helicobacter pylori antibiotic resistance revealed by extended anamnesis. A Bulgarian study. J Med Microbiol. 2012; 61(Pt 1):85-93. (IF2011-2,502)
  • Boyanova L, Mitov I. Coadministration of probiotics with antibiotics: why, when and for how long? Expert Rev Anti Infect Ther. 2012; 10(4):407-409. (doi:10.1586/eri.12.24). (IF2011: 3,283)
  • Boyanova L, Mitev A, Gergova G, Mateev G, Mitov I. High prevalence and resistance rates to antibiotics in anaerobic bacteria in specimens from patients with chronic balanitis. Anaerobe. 2012; 18: 414-416. Doi: 10.1016/j.anaerobe.2012.06.002 (IF2011: 2,409)
  • Boyanova L, Mitov I. Antibiotic resistance rates in causative agents of infections in diabetic patients. Rising concerns. Expert Rev. Anti Infect. Ther. 2013; 11 (4): 411-420. doi: 10.1586/ERI.13.19. (IF2011:3,283)
  • Boyanova L,.  Ilieva J, Gergova G, Evstatiev I, Nikolov R, Mitov I. Living in Sofia is associated with a risk for antibiotic resistance in H. pylori. A Bulgarian study. Folia Microbiol (Praha). 2013; 58 (6):587-591.(doi:10.1007/s12223-013-0251-9). (IF2011:0,677)
  • Boyanova L. Comparative evaluation of the activity of plant infusions against Helicobacter pylori strains by three methods. World J Microbiol Biotechnol. 2013 Dec 31. (IF2012: 1,262)
  • Coenen S, Muller A, Adriaenssens N, Vankerckhoven V, Hendrickx E, Goossens H; ESAC Project Group incl. B.Markova. European Surveillance of Antimicrobial Consumption (ESAC): outpatient parenteral antibiotic treatment in Europe. J Antimicrob Chemother. 2009 Jul; 64 (1): 200-5.
  • Coenen S, Adriaenssens N, Versporten A, Muller A, Minalu G, Faes C, Vankerckhoven V, Aerts M, Hens N, Molenberghs G, Goossens H on behalf of the ESAC Project Group incl. B. Markova. European Surveillance of antimicrobial consumption 1 (ESAC): Outpatient use of tetracyclines, sulfonamides and trimethoprim, and other antibacterials in Europe (1997-2009). J Antimicrob Chemother 2011, 66 Suppl 6; vi57-vi70    
  • da Silva Medeiros JA, F O Gonçalves TM, Boyanova L, de Correia Pereira MI, da Silva Paiva de Carvalho JN, de Sousa Pereira AM, Silvério Cabrita AM. Evaluation of Helicobacter pylori eradication by triple therapy plus Lactobacillus acidophilus compared to triple therapy alone. Eur J Clin Microbiol Infect Dis. 2011; 30(4):555-559. (IF2011-2,859)
  • Deccache Y, Irenge LM, Savov E, Arichiuc, Macovei A, Trifonova A, Gergova I, Ambroise J, Vanhoof R, Gala J-L. Development of pyrosequencing assay for rapid assessment of quinolone resistance in Acinetobacter baumannii isolates. J Microbiol Methods., 2011, 86: 115-118
  • Dobreva EG, Ivanov IN, Vathcheva-Dobrevska RS, Ivanova KI, Asseva GD, Petrov PK, Kantardjiev TV. Advances in molecular surveillance of Clostridium difficile in Bulgaria. J Med Microbiol., 2013, 62: 1428-1434.
  • Dogandzhiyska V., R. Gergova, S. Dimitrov, M. Doychinova, Antimicrobial activity of photodynamic therapy against microorganims isolated from deep carious lesions. IMAB, 2013; 19 (4) http://dx.doi.org/10.5272/jimab. 2013194.430
  • Gergova R., Markovska R., Mitov I. Antimicrobial resistance and production of beta-lactamases in Bulgarian clinical isolates Moraxella catarrhalis. Annals of microbiology, 2009; 59, 1, 169-172. (IF 2010 - 0.35)
  • Gergova R.T., Strateva T.V., Mitov I.G. Gardnerella vaginalis-associated bacterial vaginosis in Bulgarian women. Braz. J. Infect. Dis. 2013; 17 (3): 313-318. (IF2012–1,036)
  • ergova R, Georgieva T, Angelov I, Mantareva V, Valkanov S, Mitov I, Dimitrov S. Photodynamic therapy with water-soluble phtalocyanines against bacterial biofilms in teeth root canals. Proc. SPIE 8427, Biophotonics: Photonic Solutions for Better Health Care III, 842744, 2012; doi:10.1117/12.923859; http://dx.doi.org /10.1117 /12.923859
  • Gergova RT, Strateva TV, Mitov IG. Gardnerella vaginalis – associated bacterial vaginosis in Bulgarian women, The Brazilian Journal of Infectious Diseases, 2013; 17(3):313–318. (IF2013 - 1.036)
  • lasner C., Albiger B., Buist G., Tambić Andrasević A., Canton R., Carmeli Y., Friedrich A., Giske C., Glupczynski Y., Gniadkowski M., Livermore D., Nordmann P., Poirel L., Rossolini G., Seifert H., Vatopoulos A., Walsh T., Woodford N., Donker T., Monnet D., Grundmann H., European Survey on Carbapenemase-Producing Enterobacteriaceae (EuSCAPE) working group*. Carbapenemase-producing Enterobacteriaceae in Europe: a survey among national experts from 39 countries, February 2013. Euro Surveill. 2013 Jul 11; 18 (28). pii: 20525. *T. Strateva – participant in the EuSCAPE working group. (IF2012 5,49)
  • euleyan E. (Enhancing Infection Control with Antibiotic Stewardship – APUA Chapter Reports). APUA-Bulgaria. APUA Newsletter, 2011, vol. 29, No 3
  • Keuleyan E. pp. 183-197 In: D.Dinov, (ed). 9th International Conference SEE SECURITY, IEC, Sofia. Biological Security – strategies and priorities. DEMAX, 2011
  • Keuleyan E. Antibiotic stewardship in Bulgaria – achievements and further needs. The APUA Newsletter. 2012, 30, 20-21
  • Kotsilkov K, Popova C, Boyanova L, Setchanova L, Gergova G, Kostyanev T, Yordanov D, Mitov I. Effectiveness of the target antibiotic administration in the treatment of the severe chronic periodontitis. Journal of IMAB, Annual Proceeding (Scientific Papers) 2009, Book 2, part Dentistry (Oral and Dental Medicine), p.95-101. http://www.journal-imab-bg.org/
  • Kostyanev T, Setchanova L, Ouzounova-Raykova V, Proevska Y, Mitov I. Microbiological characterisation of Haemophilus influenzae strains isolated from patients with invasive and respiratory diseases. Online Journal of IMAB (J of IMAB), Annual Proceeding (Scientific Papers) 2010, Vol. 16, book 3: p.66-69 http://www.journal-imab-bg.org/
  • Marina S., Ouzounova-Raykova V. The most frequently used topical antibacterial agents in the dermatology practice. Scrip. Sci. Med. 2010; 42(4):245-248.
  • Marinov KT, Georgieva ED, Ivanov IN, Kantardjiev TV. Characterization and genotyping of strains of Francisella tularenses isolated in Bulgaria. J Med Microbiol, 2009, 58:82-85
  • Markovska R, I Schneider, D Ivanova, E Keuleyan, T Stoeva, M Sredkova, B Markova, K Bojkova, R Gergova, A Bauernfeind, I Mitov. 2012. High prevalence of CTX-M-15-producing O25b-ST131 Escherichia coli clone in Bulgarian hospitals. Microb Drug Resist; 18(4):390-5. IF2013-2,36
  • Markovska R., I.  Schneider, Y. Marteva-Proevska, I. Mitov, A. Bauernfeind, B. Markova .  2012. First detection of the AmpC beta-lactamase ACC-1 in a Klebsiella pneumoniae isolate in BulgariaJ Chemotherapy 24(5): 307-308. IF2012-0.83
  • Markovska R, and E Keuleyan. Extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae in Bulgaria – a short overview. The APUA NewsLetter, 31, 2013, 2:17-18
  • Markovska R, Schneider I, Stoeva T, Bojkova K, Boyanova L, Bauernfeind A, Mitov I. First identification of KPC-2 and VIM-1 producing Klebsiella pneumoniae in Bulgaria. Diagn Microbiol Infect Dis. 2013 Nov;77(3):252-3. С. IF2012-2,53
  • Markovska RD, Stoeva TJ, Bojkova KD, Mitov IG. Epidemiology and Molecular Characterization of Extended-Spectrum Beta-Lactamase-Producing Enterobacter spp., Pantoea agglomerans, and Serratia marcescens Isolates from a Bulgarian Hospital. Microb Drug Resist. 2013 Oct 30. [Epub ahead of print]. IF2013-2,36
  • Markovska R, Schneider I, Ivanova D, Mitov I, Bauernfeind A. Predominance of IncL/M and IncF plasmid types among CTX-M-ESBL-producing Escherichia coli and Klebsiella pneumoniae in Bulgarian hospitals. APMIS. 2013 Dec 5. doi: 10.1111/apm.12204. [Epub ahead of printIF2012-2,07
  • Mitov, I.G., Gergova, R.T., Ouzounova-Raykova V.V. Distribution of genes encoding virulence ompB2, ompCD, ompE, beta-lactamase and serotype in pathogenic and colonizing strains Moraxella catarrhalis, Archives of medical research, 2010; 41, 7, 530-535. (IF2011–1,733)
  • Nashev D, Bizeva L, Merdzhanov D, Keuleyan E, Kantardjiev T. Characterization of methicillin-resistant Staphylococcus aureus in Bulgarian hospitals, 2005 – 2011. The APUA NewsLetter, 31, 2013, 3:17-19
  • Ouzounova-RaykovaV., El Tibi M., Mitov I. The first simultaneous study of the prevalence of Neisseria gonorrhoeae and Chlamydia trachomatis infections by PCR and standard methods in patients attending different clinics in Sofia, Bulgaria. Sex. Health. 2011, 8:442-444. (IF2012–1,645)
  • Ouzounova-Raykova V., Jordanov D., El-Tibi M., Mitov I. Gonococcal infection in symptomatic and asymptomatic persons seeking medical clinics in Sofia. A 3-year study 2008-2010. Ac. Path. Microbiol. et Immunol. Scand. 2011;  119 (12): 864-867. (IF2012–2,068)
  • Ouzounova-Raykova V., Ouzounova I., Mitov I. Chlamydia trachomatis infection as a problem among male partners or infertile couples. Andrologia. 2009, 41, 14–19. (IF2010–1,244)
  • Ouzounova-Raykova V., El-Tibi M., Ouzounova I., Mitov I. Detection of genital mycoplasmas in men attending medical clinics in Sofia, Bulgaria. Scrip. Scientif. Med., 2013; 45(4): 46-49.
  • Petrova G., Strateva T., Ulevinov N., Perenovska P. Immunoglobulin levels, cytology and microbiologic investigations on broncho-alveolar lavage in children with cystic fibrosis. Braz. J. Infect. Dis. 2013; 17 (2): 272-273. (IF2012–1,036)
  • Poirel L, Savov E, Nazli A et al. Outbreak caused by NDM-1- and RmtB-Producing Escherichia coli in Bulgaria. Antimicrob Agents Chemother., 58, 2014, 4: 2472-2474
  • Rosental VD, Bijie H, Maki DG…Hadjieva N…. International Infection Control Consortium (INICC) report, data summary of 36 countries, for 2004-2009. Am J Infect Control. 2012, 40: 396-407
  • Schneider I, Markovska R, Marteva-Proevska Y, Mitov I, Markova B, Bauernfeind A. Detection of CMY-99, a Novel Acquired AmpC-Type β-Lactamase, and VIM-1 in Proteus mirabilis Isolates in Bulgaria. Antimicrob Agents Chemother. 2014 Jan;58(1):620-1. IF2012- 4.57
  • Schneider I, Queenan AM, Markovska R, Markova B, Keuleyan E, Bauernfeind A. 2009. New variant of CTX-M-type extended-spectrum beta-lactamases, CTX-M-71, with a Gly238Cys substitution in a Klebsiella pneumoniae isolate from Bulgaria. Antimicrob Agents Chemother. 53(10):4518-4521. IF 2010 –  4.67
  • Setchanova L, Alexandrova A, Mitov I, Nashev D, Kantardjiev T, The Group for Microbiological surveillance of pneumococci (M. Murdjeva). Serotype Distribution and Antimicrobial Resistance of Invasive Streptococcus pneumoniae Isolates in Bulgaria before the Introduction of Pneumococcal Conjugate Vaccine. J Chemother. 2012; 24 (1):12-17. (IF2011 – 1.084)
  • Setchanova L, Kostyanev T, Markovska R, Miloshev G, Mitov I. Serotypes, antimicrobial susceptibility and β-lactam resistance mechanisms of clinical Haemophilus influenzae isolates from Bulgaria in a pre-vaccination period. Scand J Infect Dis 2013; 45 (2):81-87. doi:10.3109/00365548.2012.710854. Epub 2012 Sep 19. (IF2011 - 1.722)
  • Setchanova L, Kostyanev T, Alexandrova A, Mitov I, Nashev D, Kantardjiev T. Microbiological characterization of Streptococcus pneumoniae and non-typeable Haemophilus influenzae isolates as primary causes of acute otitis media in Bulgarian children before the introduction of conjugate vaccines. Annals of Clinical Microbiology and Antimicrobials. 2013;12:6.    doi:10.1186/1476-0711-12-6. (IF2013 - 1.7)
  • Stoeva T, Higgins PG, Savov E, Markovska R, Mitov I, Seifert H. 2009. Nosocomial spread of OXA-23 and OXA-58 beta-lactamase producing Acinetobacter baumanii in Bulgarian hospitals. J Antimicrob Chemother. 63(3):618-620. IF 2010 – 4.66
  • Stoyanova A, Hitkova H, Bachvarova-Nedelcheva A, Iordanova R, Ivanova N, Sredkova M. Synthesis, photocatalytic and antibacterial properties of nanosized ZnTiO3 powders obtained by different sol-gel methods. Digest J Nanomat Biostruct., 7, 2012, 2:777-784
  • Stoyanova A, Hitkova H, Bachvarova-Nedelcheva A, Iordanova R, Ivanova N, Sredkova M. Synthesis and antibacterial activity of nanocomposites prepared via nonhydrolytic route. J Chem Technol Metallurgy., 48, 2013, 2, 154-161  
  • Strateva T., Petrova G., Perenovska P., Mitov I.. Bulgarian cystic fibrosis Pseudomonas aeruginosa isolates: antimicrobial susceptibility and neuraminidase-encoding gene distribution. J. Med. Microbiol. 2009; 58 (5): 690-692. (IF2010–2,380)
  • Strateva T., Yordanov D. Pseudomonas aeruginosa – a phenomenon of bacterial resistance. J. Med. Microbiol. 2009; 58 (9): 1133-1148. (IF2010–2,380)
  • Strateva T., Markova B., Ivanova D., Mitov I. Distribution of the type III effector proteins-encoding genes among nosocomial Pseudomonas aeruginosa isolates from Bulgaria. Ann. Microbiol. 2010; 60 (3): 503-509. (IF2011–0,689)
  • Strateva T., Petrova G., Mitov I. Antimicrobial activity of tobramycin against respiratory cystic fibrosis Pseudomonas aeruginosa isolates from Bulgaria. J. Chemother. 2010; 22 (6):378-383. (IF2011–1,084)
  • Strateva T., Markova B., Markovska R., Marteva-Proevska Y., Ivanova D., Mitov I. Emergence of 16S rRNA methylase-producing nosocomial Acinetobacter baumannii isolates in a University hospital in Bulgaria. J. Chemother. 2011; 23 (6): 374-375.            (IF2012–0,825)
  • Strateva T., Markova B., Marteva-Proevska Y., Ivanova D., Mitov I. Widespread dissemination of multidrug-resistant Acinetobacter baumannii producing OXA-23 carbapenemase and ArmA 16S ribosomal RNA methylase in a Bulgarian university hospital. Braz. J. Infect. Dis. 2012; 16 (3): 307-310. (IF2012–1,036)
  • Strateva T., Kostyanev T., Setchanova L. Ralstonia pickettii sepsis in a hemodialysis patient from Bulgaria. Braz. J. Infect. Dis. 2012; 16 (4): 400-401. (IF2012–1,036)
  • Strateva T., Petrova G., Stratev A., Perenovska P., Mitov. I. Etiology of bronchopulmonary infections in Bulgarian cystic fibrosis patients. Braz. J. Infect. Dis. 2013; 17 (5): 617-618. (IF2012–1,0)
  • Todorova B, Velinov T, Ivanov I, Dobreva E, Kantardjiev T. First detection of OXA-24 carbapenemase-producing Acinetobacter baumannii isolates in Bulgaria. World J Microbiol Biotechnol., 2014, 30:1427 – 1430
  • Valcheva V, Mokrousov I, Panaiotov S, Bachiiska E, Zozio T, Sola C, Markova N, Rastogi N. Bulgarian specificity and controversial phylogeography of Mycobacterium tuberculosis spoligotype ST 125_BGR. FEMS Immunol Med Microbiol. 2010, 59:90-99
  • Vatcheva – Dobrevska R, Mulet X, Ivanov I, Zamorano L, Dobreva E, Velinov T, Kantardjiev T, Oliver A. Molecular Epidemiology and Multidrug Resistance Mechanisms of Pseudomonas aeruginosa Isolates from Bulgarian Hospitals. Microbial Drug Resistance. October 2013, 19(5): 355-361.
  • Versporten A, Coenen S, Adriaenssens N, Muller A, Minalu G, Faes C, Vankerckhoven V, Aerts M, Hens N, Molenberghs G, Goossens H on behalf of the ESAC Project Group incl. B.Markova. European Surveillance of Antimicrobial Consumption (ESAC): Outpatient penicillin use in Europe. J Antimicrob Chemother 2011, 66 Suppl 6; vi13-vi23      
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