TABLE OF CONTENT

dl

1. CARBAPENEMASE-PRODUCING GRAM-NEGATIVE BACTERIA IN BULGARIA – CURRENT STATUS

K.R. Ivanova

ABSTRACT
The emergence and spread of carbapenem resistance among Gram-negative bacteria is a serious clinical and public health concern. Carbapenem-resistant (CR) pathogens can acquire genes encoding multiple antibiotic resistance mechanisms and have the potential to develop multidrug-resistant and pan-resistant phenotypes. Early diagnosis, active surveillance, and prevention of infections are necessary in order to develop strategies to limit their spread. For the past ten years CR Enterobacteriaceae, Pseudomonas spp., and Acinetobacter spp. have been identified in major regional hospitals in the country.


2. MULTILOCUS SEQUENCE TYPING OF MULTI-DRUG RESISTANT BACTERIA IN THE ERA OF WHOLE GENOME SEQUENCING

V. Dobrinov

ABSTRACT
Over the past three decades molecular genetics methods for identification and typing of high-risk strains are developing very rapidly. Their role is crucial in elucidating epidemiological dissemination of multi-drug (MDR) and pan-drug resistant (PDR) bacterial clones. While the Whole Genome Sequencing (WGS) technologies are increasingly adopted for typing and surveillance of antimicrobial resistant bacteria, the basic concepts and bioinformatic databases used are derived from the Multilocus Sequence Typing (MLST) that long has been considered the “main stage” for phylogenetic studies. Here we review the MLST approaches for typing of the MDR bacteria with public health significance.


3. MYCOPLASMA GENITALIUM: PREVALENCE AND CLINICAL SIGNIFICANCE IN SOFIA MUNICIPALITY

I. Philipova, A. Kouzmanov, Z. Ivanova, V. Kantardjiev

ABSTRACT
Mycoplasma genitalium as an etiological cause of bacterial sexually transmitted infections (STIs) has been of increasing interest in recent years. This study is one of the very few prevalence studies concerning M.genitalium among Bulgarian population. The recorded prevalence of M. genitalium was 2.45%. Moreover, the association between M. genitaliumand genital tract infections such as urethritis and cervicitis was likewise affirmed in the present study. Further research is still needed for obtaining antimicrobial resistance data on M. genitalium to secure effective control and optimal treatment of bacterial STIs.


4. MYCOBACTERIUM TUBERCULOSIS INFECTION RATES IN EXPOSED BULGARIAN HEALTHCARE WORKERS BASED ON INTERFERON-GAMMA RELEASE ASSAYS

R. Emilova, V. Milanov, M. Tyufekchieva, M. Muhtarova, M. Zamfirova, D. Stefanova, T. Varleva, N. Gesheva, A. Mihaylova, E. Naumova, M. Nikolova

ABSTRACT
Background: The incidence of tuberculosis (TB) in Bulgaria remains higher than the average for EU/EEC countries. Healthcare workers (HCWs) providing TB care are at increased risk of MTB infection. Interferon-gamma release assays (IGRAs) are an accurate means for diagnosis of MTB infection. Objectives: The study aims to assess the prevalence of MTB infection among exposed HCWs in Bulgaria based on IGRAs as screening tools.

Methods: Data about age, sex, professional category and employment history were collected. Screening was performed in four rounds (2012, 2014, 2015 and 2016), using QuantiFERON-TB® Gold in-tube assay (QFT-GIT) and T-SPOT.TB assay.

Results: A total of 633 HCWs from 37 specialized healthcare facilities were tested, including medical doctors (22.7%), nurses (34.8%), laboratory workers (16.6%), cleaning staff (20.1%) and administrative personnel (5.8%). A positive IGRA result was obtained in 260 (41%) HCWs. Positive results were associated with higher age but not with gender, professional category or employment duration. Unclassifiable results (4.3%) were obtained mostly with T-Spot, and in the elderly HCWs. Consecutive testing in 125 (19.7%) HCWs revealed a significant share of reversions and conversions (30.4%) requiring retesting/follow-up. The quantity of MTB-specific IFNγ measured by QFT-GIT was not directly associated with infection duration, activity, or MTB-specific treatment.

Conclusion: HCWs providing TB care in Bulgaria are at increased risk of MTB infection. Occupational screening programs with focus on the elderly HCWs should be routinely applied in high-risk settings. Retesting “close to zero” results and combining sequential IGRAs with detailed history, clinical examination, and radiography would improve the efficiency of screening.


5. CLINICAL AND EPIDEMIOLOGICAL FEATURES OF PERTUSSIS CASES IN PLEVEN REGION

G. Gancheva, I. Pakov, V. Levterova, T. Doichinova

ABSTRACT
Pertussis is a vaccine-preventable disease. During recent years, there is a trend of increasing incidence especially in non-immunised. Our aim was to study the clinical and epidemiological features of pertussis cases.

Material and Methods: This study was carried out as a retrospective analysis of 28 pertussis cases treated in the Clinic of Infectious Diseases at University Hospital – Pleven between 2009 and 2016.

Results: 64% of the cases were up to one year of age, 21% – one to three years old. Male to female ratio was 1 to 1.8. 36% of the cases were registered during February to March and 25% in June. The children up to one year of age were not immunised due to premature birth, hypotrophy, and frequent illnesses. All cases were treated with antibiotics before admission. The initial symptom was racking cough, followed by whooping sound, flushed face or cyanosis. Fever was registered in 29%. Pneumonia and bronchitis were found by X-ray in 14 and 21%, respectively. Laboratory investigations revealed leucocytosis in 86%, lymphocytosis in 93%, and increased platelet count in 86%. Real-time PCR was performed in 57% of the cases and gave positive result in 62.5% of the tested children. The patients were treated with antibiotics (cephalosporins in 71%, ampicillin in 25%), corticoids (in 82%), and expectorant. The median duration of hospital treatment was eight days.

In conclusion: The trend of increased incidence of pertussis requires further studies on the clinical, epidemiological, and immunological aspects.


6. INFECTIOUS AGENTS DURING PREGNANCY - PRELIMINARY STUDY

S. Voleva, A. Pavlova, P. Genova-Kalou, V. Manolov, B. Marinov, St. Shishkov

ABSTRACT
The objective of this study was to determine the frequency of evidence of any infectious agents during pregnancy.

Material and Methods: The present study included 38 serum samples from women with pathological pregnancy collected in the first half of 2017. The following methods were used: serological - indirect enzyme immunoassay (EIA) test for detection of specific IgM antibodies for measles, rubella, parvovirus B19, Coxiella burnetii, Chlamydia trachomatis; and molecular - extraction and detection of infectious nucleic acids with PCR assay and electrophoresis in 2% agarose gel to visualise the PCR products.

Results: During the first half of 2017 a total of 38 serum samples from women with pathological pregnancy were tested with enzyme-linked immunosorbent assay and molecular methods. Specific primary reactive B19-IgM were found in 3/38 (7.89%) of the patients. Positive IgM results for C. trachomatis and C. burnetii Ph. II were found in 3/38 (7.89%) and 2/38 (5.26%), respectively. B19V seroprevalence (presence of specific B19V-IgG antibodies) of the tested group was calculated as 55.26 %. Positive C. trachomatis and C. burnetii Ph. II IgG results were shown in 9/38 (23.68 %) and 2/38 (5.26%) of the patients. All tested samples were serologically negative for acute measles and rubella infections and had protective immunity.

Conclusion: The combined laboratory approach for determining acute infection (detection of specific IgM/IgG antibodies and nucleic acid) is of particular importance for correct diagnosis and in the monitoring of cases of pathological pregnancy. Among the investigated clinical cases of pregnant women, the presence of acute B19V, C. burnetii, and C. trachomatis infections did not dominate, and measles and rubella were not detected.


7. PREVALENCE OF POLYOMAVIRUS KIPyV IN BULGARIAN PATIENTS WITH RESPIRATORY DISEASES

E. Shikova, D. Emin, А. Kumanova, D. Alexandrova, M. Shindov

ABSTRACT
Background: The role of polyomavirus KIPyV as a respiratory pathogen still remains controversial. Little is known about the oncogenicity of KIPyV. The aim of this study was to determine the prevalence of KIPyV in patients with acute respiratory diseases and chronic lung diseases, including lung cancer, in order to evaluate the association between KIPyV infection and respiratory diseases.

Material and methods: This study included 221 specimens (nasopharyngeal swabs and lung biopsy specimens) obtained from patients with acute respiratory diseases and chronic lung diseases, including lung cancer. Detection of KIPyV was performed by nested PCR.

Results: KIPyV positivity was 5.9 % on average. All nasopharyngeal specimens were obtained from patients with acute respiratory diseases and 10.3% of them were KIPyV-positive. Among children aged 12 years or less KIPyV prevalence was higher than that in patients older than 12 years. We found 2.8% KIPyV positivity rate among patients with noncancer chronic lung diseases. All specimens from lung cancer cases were KIPyV-negative.

Conclusions: KIPyV was more prevalent among patients with acute respiratory diseases, especially children, indicating that there may be a relationship between the virus and these diseases. The prevalence is very low in chronic lung diseases, suggesting no association with KIPyV infection. We were not able to detect KIPyV in samples from patients with lung cancer, indicating no oncogenic potential of this polyomavirus.


8. UV SURFACE DISINFECTION USING GERMICIDAL LAMPS: A STUDY ON THE OPTIMAL UVC INTENSITY AND THE OPTIMAL EXPOSURE TIME

M. Nikolova

ABSTRACT
Background: The implementation of ultraviolet light (UV) irradiation has been suggested as a supplement technology to the standard protocols for terminal cleaning and disinfection of room surfaces. Our previously published questionnaire study indicated the widespread use of germicidal lamps in healthcare facilities in Bulgaria, as well as the need for updated recommendations to ensure their effective usage. The aim of the present study was to define the optimal UVC intensity and the optimal exposure time when using germicidal lamps for disinfection of contaminated surfaces.

Material and methods: A test suspension of microorganisms (Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus hirae, and Candida albicans) was spread on a petri dish with nutrient agar. The plates were placed at different distance from the UV lamp, with different UVC intensity reaching the plates: 4 μWs/cm2 (distance to the germicidal lamp - approximately 3 metres), 8 μWs/cm2, 15 μWs/cm2 (2 - 2.5 metres), and 20 μWs/cm2 (approx. 1 metre). The plates were exposed to varied UVC intensity for varied time periods: 5 min, 15 min, 30 min, 45 min, 60 min, and 90 min.

Results: With the lowest UVC intensity (4 μWs/cm2), germicidal effect was observed at 90 minutes of exposure. When 8 μWs/cm2 UVC intensity reached the inoculated plates, germicidal effect was observed at 30 minutes. UV surface disinfection for 15 minutes is adequate when UVC intensity of ≥ 15 μWs/cm2 is used.

Conclusions: The ceiling-mounted germicidal UV tubes are effective for surface disinfection when exposure time is 15-30 minutes and UVC intensity at each part of the irradiated surface is ≥ 8 μWs/cm2.


 

 Editor-in-Chief
Prof. Todor Kantardjiev, MD, PhD, DSc– NCIPD, Sofia, Bulgaria

Editorial Board:
Prof. Iva Christova, MD, DSc – NCIPD, Sofia, Bulgaria
Richard Anthony, PhD – RIVM, The Netherlands
Dale Barnard, PhD – Utah State University, USA
Roger Hewson, PhD – WHO Collaborating Centre for Virus Research & Reference, Porton Down, UK
Judith M. Hübschen – Luxembourg Institute of Health, Luxembourg
Emad Mohareb, PhD– U.S. Naval Medical Research Unit No.3, Egypt
Bruno Gottstein – Institute of Parasitology, University of Berne, Switzerland
Anton Andonov, PhD – Public Health agency, Canada
Anna Papa-Konidari, PhD- Aristotle University, Thessaloniki, Greece
Anna Erdei, DSc - Eötvös L. University, Budapest, Hungary
Lanfranco Fattorini – Instituto Superiore di Sanita, Italy
Hannes Stocklinger, PhD – Medical University, Vienna, Austria
Acad. Bogdan Petrunov, MD, DSc – NCIPD, Sofia, Bulgaria
Assoc. Prof. Iskra Rainova, MD, PhD – NCIPD, Sofia, Bulgaria
Assoc. Prof. Lubomira Nikolaeva-Glomb, MD, PhD – NCIPD, Sofia, Bulgaria

Please publish modules in offcanvas position.

This site uses COOKIES to ensure optimal user experience.