Serogroup diversity and antibiotic susceptibility of Neisseria meningitidis: Meningococcus infection monitoring in Belarus.

This study performed an epidemiological survey of Neisseria meningitidis strains isolated from patients and from asymptomatic carriers. Altogether, 74 N. meningitidis strains (46 invasive and 28 non-invasive) were isolated between February 2011 and May 2018 in different regions of the Republic of Belarus. Serogenotyping was carried out by real-time PCR. Minimum inhibitory concentrations (MICs) of antibiotics were determined by broth microdilution and results were interpreted in accordance with EUCAST. The serogroups of N. meningitidis were determined as follows: serogroup B - 65%, C - 11%, W - 9%, A - 5%, Y - 4%, and Z and NG - 3% each. The MIC50 and MIC90 for benzylpenicillin (0.032/0.064-0.125 mg/L), ampicillin (0.032/0.125 mg/L), amoxicillin (0.125/0.25 mg/L), cefotaxime (0.016/0.016 mg/L), ceftriaxone (0.002/0.016 mg/L), ciprofloxacin (0.004/0.008 mg/L), chloramphenicol (1/1 mg/L), meropenem (0.008/0.008-0.016 mg/L), tetracycline (0.25/0.5 mg/L), and rifampicin (0.016/0.25 mg/L) were established. Strains with intermediate susceptibility for benzylpenicillin (12.3%), ampicillin (6.8%), and amoxicillin (24.7%) have been identified. In this study, we report the first rifampicin-resistant N. meningitidis in Belarus.

Study of carD gene sequence in clinical isolates of Mycobacterium tuberculosis.

Mycobacterium tuberculosis growth rate is closely coupled to rRNA transcription which is regulated through carD gene. The aim of this study was to determine the sequence of carD gene in drug susceptible and resistant clinical isolates of M. tuberculosis and designing of a PCR assay based on carD sequence for rapid detection of this bacterium.Specific primers for amplification of carD gene were carefully designed, so that whole sequence of gene could be amplified; therefore primers were positioned at the upstream (promoter of this gene and ispD gene) and downstream (in ispD gene). DNA from 41 clinical isolates of M. tuberculosis with different pattern of drug resistance was used in the study. PCR conditions and annealing temperature were designed by means of online programs. PCR products were sequenced by ABI system.PCR product of carD gene was a 524 bp fragment. This method could detect all resistant and susceptible strains of M. tuberculosis. The size of amplified fragment was similar in all investigated samples. Sequence analysis showed that there was similar sequence in all of our isolates therefore probably this gene is considered to be conservative. Translation of nucleotide mode to amino acids was showed that TRCF domain in N-terminal of protein CarD was found to be fully conservative.This is the first study on the sequence of carD gene in clinical isolates of M. tuberculosis. This conservative gene is recommended for use as a target for designing of suitable inhibitors as anti-tuberculosis drug because its importance for life of MTB. In the other hand, a PCR detection method based on detection of carD gene was recommended for rapid detection in routine test.

Evolutionary epidemiology of Neisseria meningitidis strains in Belarus compared to other European countries.

INTRODUCTION: Meningococcal infections are major causes of death in children globally. In Belarus, the incidence of cases and fatality rate of meningococcal infections are low and comparable to the levels in other European countries. AIM: In the present study, the molecular and epidemiological traits of Neisseria meningitidis strains circulating in Belarus were characterized and compared to isolates from other European countries. MATERIALS AND METHODS: Twenty N. meningitidis strains isolated from patients (n = 13) and healthy contacts (n = 7) during 2006­2012 in Belarus were selected for multilocus sequence typing (MLST), genosubtyping and FetA typing. TheSTs of the Belarusian strains were phylogenetically compared to the STs of 110 selected strains from 22 other European countries. RESULTS: Overall, eleven different genosubtypes were observed, there were seven variants of variable region of the fet Agene detected. The majority of the STs (95%) found in Belarus were novel and allthose were submitted to the Neisseria MLST database for assignment. Several newly discovered alleles of fumC (allele 451) and gdh (allele 560 and 621) appeared to be descendants of alleles which are widespread in Europe, and single aroE alleles (602 and 603) occurred as a result of separate evolution. CONCLUSIONS: N. meningitidis strains circulating in Belarus are heterogeneous and include sequence types, possibly, locally evolved in Belarus as well as representatives of widespread European hyperinvasive clonal complexes.

Determination of principal genotypic groups among susceptible, MDR and XDR clinical isolates of Mycobacterium tuberculosis in Belarus and Iran.

INTRODUCTION: All members of the Mycobacterium tuberculosis complex were assigned to one of the three principle genetic groups based on KatG463/GyrA95 polymorphism. MATERIALS AND METHODS: A total of 202 isolates of M. tuberculosis consisting of 50 susceptible, 121 MDR (multidrug resistant) and 31 XDR (extensively drug resistant) isolated from culture-confirmed tuberculosis patients in different regions of Belarus and Iran (Tehran and Markazi province). Isolates were screened by sequencing and polymerase chain reaction restriction fragment length polymorphism (RFLP) assay, and were further divided into three principal genetic groups (PGG), based on Sreevatsan's pattern as polymorphisms in KatG463/GyrA95 codons. RESULTS: Among the 104 isolates, characterized as MDR from Belarus, 57 (54.8 ± 4.8%), 30 (28.8 ± 4.43%), 17 (16.3 ± 3.6), belonged to PGG 1, 2, and 3, respectively (p< 0.05). Thirty one XDR isolates from Belarus had a similar pattern as 15 (48.4%), 12 (38.7%), 4 (12.9%) PGG 1, 2, and 3, respectively. From Iranian samples, Markazi isolates (susceptible to drugs) had a pattern as 12 (36.5%), 15 (45.5%), 3 (6%), and Tehran samples were (selected MDR): 9 (53%), 6 (35.2%), 2 (11.8%) (PGG 1, 2, and 3, respectively). In a study of tuberculosis patients, who were in prison, no relation was found between PGG and resistance to isoniazid, but most of the identified isolates belonged to PGG 1 (45.5 ± 10.9%) (p< 0.05). Overall, the group 1 isolates showed more frequency in MDR and XDR rather than susceptible strains, and there aren't any relations to geographic region.

High level isoniazid resistance correlates with multiple mutation in the katG encoding catalase proxidase of pulmonary tuberculosis isolates from the frontier localities of Iran.

The aim of this study was to investigate the significance of multiple-mutations in the katG gene, predominant nucleotide changes and its correlation with high level of resistance to isoniazid in Mycobacterium tuberculosis isolates that were randomly collected from sputa of 42 patients with primary and secondary active pulmonary tuberculosis from different geographic regions of Iran. Drug susceptibility testing was determined using the CDC standard conventional proportional method. DNA extraction, katG gene amplification, and DNA sequencing analysis were performed. Thirty four (80%) isolates were found to have multiple-mutations (composed of 2-5 mutations) in the katG gene. Increased number of predominant mutations and nucleotide changes were demonstrated in codons 315 (AGC-->ACC), 316 (GGC-->AGC), 309 (GGT-->GTT) with a higher frequency among patients bearing secondary tuberculosis infection with elevated levels of resistance to isoniazid (MIC ≥ 5-10 µg/mL). Furthermore, it was demonstrated that the combination of mutations with their predominant nucleotide changes were also observed in codons 315, 316, and 309 indicating higher frequencies of mutations among patients with secondary infection respectively. In this study, 62% (n= 21) of multi-mutated isolates found to have combination of mutations with predominant nucleotide changes in codons 315 (AGC-->ACC), 316 (GGC-->GTT), 309 (GGT-->GGT), and also demonstrated to be more frequent in isolates of patients with secondary infections, bearing higher level of resistance to isoniazid (≥ 5-10 µg/mL).

High-level rifampin resistance correlates with multiple mutations in the rpoB gene of pulmonary tuberculosis isolates from the Afghanistan border of Iran.

The aim of this study was to investigate the significance of multiple mutations in the rpoB gene as well as predominant nucleotide changes and their correlation with high levels of resistance to rifampin (rifampicin) in Mycobacterium tuberculosis isolates that were randomly collected from the sputa of 46 patients with primary and secondary cases of active pulmonary tuberculosis from the southern region (Afghanistan border) of Iran where tuberculosis is endemic. Drug susceptibility testing was performed using the CDC standard conventional proportional method. DNA extraction, rpoB gene amplification, and DNA sequencing analysis were performed. Thirty-five (76.09%) isolates were found to have multiple mutations (two to four) in the rpoB (beta-subunit) gene. Furthermore, we demonstrate that the combination of mutations with more prevalent nucleotide changes were observed in codons 523, 526, and 531, indicating higher frequencies of mutations among patients with secondary infection. In this study, 76.08% (n = 35) of all isolates found to have mutation combinations involving nucleotide changes in codons 523 (GGG-->GCG), 531 (TCG-->TTG or TTC), and 526 (CAC-->CGC, TTC, AAC, or CAA) demonstrated an association with higher levels of resistance to rifampin (MIC, >or=100 microg/ml).

RETRACTED: High level Rifampin Resistance Correlates with Multiple Mutations in the rpoB Gene of Pulmonary Tuberculosis Isolates from the Afghanistan Border of Iran.

This article has been retracted.

katG mutations in isoniazid-resistant strains of Mycobacterium tuberculosis isolates from Belarusian patients.

The aim of this study was to investigate the frequency, location and type of katG mutations in Mycobacterium tuberculosis strains isolated from patients in Belarus. Mutations in different codons causing resistance to isoniazide in the gene of catalase peroxides (katG) in Belarusian strains was determined. 42 strains of Rif-r and Inhr(MDR) were isolated in different regions of Belarus. Culture susceptibility testing of all 42 strains revealed resistance to streptomycin (90%), 16 strains (43%) were resistant to etambutol. DNA Extraction, Standard PCR identification and katG gene amplification were performed. The most affected codons of katG gene were 315(95%), 316(16.2%), and 309(14.5%). Four types of mutations were identified in codon 315: AGC-->ACC (n=36)32.4%, AGC-->AGG (n=1) 0.9%, AGC-->AAC (n=2) 1.8%, AGC-->GGC (n=1) 0.9%. One type of mutation was found in codon 316: GGC-->AGC (n=18)16.2%, four types of mutations were detected in codon 309: GGT-->GGT (n=7)6.3%, GGT-->GCT (n=4)3.6%, GGT-->GTC (n=3)2.7%, GGT-->GGG (n=1)0.9%. Mutations in codon 309 make up 34%, in codon 316 (37%) and other types of mutations 29% of all detected mutations. In 2 isolated strains mutation were identified in codons 463, 35 and, in codons 454, 357 respectively and 2 isolates, there were not found any mutations. Concluding, all INH-r MBT had resistance-associated nucleotide changes mostly in codons 315.

Identification of mutations in the rpoB encoding the RNA polymerase beta subunit in rifampicine-resistant Mycobacterium tuberculosis strains from Iran.

The aim of this study was to investigate the frequency, location and type of rpoB mutations in Mycobacterium tuberculosis isolated from patients in Iran. 91 sputum were collected from suspected tuberculosis patients, 34 Rif-r isolates (87%) were identified as M. tuberculosis. Polymerase chain reaction (PCR) amplification and DNA sequencing methods were performed. 411 bp fragments of rpoB gene were sequenced and mutations in 81 bp regions were analyzed. 60 mutations and 13 micro deletions were identified in 29 RIF-r MBT (85%). Among 60 mutations, 6 silent and 54 missense were identified. Missense mutations produced 23 types of amino acid substitutions. In 5 RIF-r MBT isolates (15%) no mutations were found in the core region of the rpoB gene. All silent mutations were localized in codon 507. Most frequent mutations detected from Iranian strains were in codons 523 and 526. Five alleles in codon 526 and 3 alleles in triplets in each codons 507, 508, 513 were found. 6 (19%) strains harboured single mutations 6 (18%) placed in codons 526, 510 while the rest of isolates 23 (69%) had multiple mutations: Double 11 (34%), triple 7 (22%), and quartile mutations 1 (3%) and 4 (12%) of strains harboured 5 mutations respectively.

Molecular characterization of rpoB gene mutations in rifampicine-resistant Mycobacterium tuberculosis isolates from tuberculosis patients in Belarus.

The aim of this study was to investigate the frequency, location and type of rpoB mutations in Mycobacterium tuberculosis isolated from patients in Belarus. Tuberculosis cases are increasing every year in Belarus. Moreover, resistance to anti-tuberculosis drugs, especially to rifampicine, has increased. In this study, 44 rifampicine-resistance M. tuberculosis clinical isolates (including multidrug-resistant isolates) were subjected to DNA sequencing analysis of the hypervariable region (hot-spot) of the rpoB gene originating from different geographical regions in Belarus. Sixteen different types of mutations were identified. The most common point mutations were in codons 510 (47.7%), 526 (45.5%), 523 (40.86%) and 531 (29.5%). Eleven isolates (27.7%) carried one mutation and 23 (52%), 7 (16%), 3 (7%) of isolates carried 2, 3 and 4 mutations, respectively. A characteristic, prominent finding of this study was high frequency of multiple mutations in different codons of the rpoB gene (27.7%) and also the detection of unusual types of mutations in the 510 codon, comprising CAG mutations (deletion or changing, to CTG, CAC or CAT). In our study, the change TTG in codon 531 was found in 92% of isolates and the change TGC in 8% of isolates. A TAC change in codon 526 was not found, but the GAC change was found in all isolates. Isolates of M. tuberculosis isolated in Belarus were characterized by the wide spectrum of the important mutations and might belong to the epidemic widespread clones.

Antibiotic policies in Central Eastern Europe.

To assess the antibiotic policies in Central Eastern European (CEE) countries, a questionnaire on the prevalence of resistance, antibiotic consumption data for ambulatory and hospital care and antibiotic policies, was mailed to national representatives. Data on antibiotic resistance and consumption of antibiotics at national levels are limited and vary considerably among countries. The importance of surveillance data in altering perceptions of the prevalence of resistance is shown by the comparison of surveillance data and interview data. Interview data without surveillance data produced the widest range of estimates of the prevalence of resistance in streptococcus pneumonia -5% in Lithuania and 82% in Belarus. The average consumption of antibiotics in ambulatory care in eight CEE countries in 2001 was 19.35 defined daily doses (DDD)/1000 inhabitants per day, (range 13.1 - 24.8 DDD) and in hospitals in six CEE countries was 2.2 DDD/1000 inhabitants per day (range 1.3-4.5). Over the counter sales of antibiotics are available in some countries. Antibiotic policy interventions do not exist or only apply to specific problems or interventions. Better implementation of antibiotic interventions and education on antibiotic use should be a high priority in this region. An effective strategy requires close co-operation, consultations and partnership at national and international level in particular, via existing international organisations.