Bacteriological Methods Research Articles

Microbiological monitoring of antibiotic resistance of strains of Streptococcus agalactiae among pregnant women

Group B Streptococcus (GBS) is the causative agent in 2–7% of all urinary tract infections (UTI), including asymptomatic bacteriuria (AB), cystitis, and pyelonephritis. We used the bacteriological quantitative method of sowing urine samples of pregnant women on Columbia agar with 5% lamb blood), Strepto B chromogenic agar and Todd Hewitt broth, identification of GBS strains with determination of sensitivity to bacitracin, hippurate hydrolysis test and CAMP test. Susceptibility to antimicrobial drugs was determined by the disk-diffusion method according to recommendations of the European Committee on Antimicrobial Susceptibility Testing. For the period of 2021, out of 3,356 urine samples of pregnant women, there were 149 samples of the investigated biomaterial with a positive result for GBS (resultancy – 4.4%). It was established that among the studied contingent, 41 strains of GBS were isolated in the first trimester of pregnancy (27.5%), in the second trimester – 59 strains (39.5%), in the third trimester – 49 strains (33.0%). It is established that out of the 149 strains of GBS, 38 strains (25.0%) were resistant to norfloxacin, 45 strains (30.0%) to erythromycin, 41 strains (28.0%) to clindamycin,125 strains (84.0%) to tetracycline, 20 strains (13.0%) to levofloxacin, 3 strains (2.0%) to nitrofurantoin. All strains of Streptococcus agalactiae were found to be sensitive to benzylpenicillin. The number of resistant strains of SGB identified from the urine of pregnant women was 47 strains. All resistant strains were resistant to at least three groups of antibacterial drugs, except beta-lactams. The results of the scientific research will allow us to obtain dynamic data on the antibiotic resistance of GBS strains in order to study the rate of development of antibiotic sensitivity of this microorganism. In the future, the research data can be used by scientists when reviewing protocols for the treatment of urinary tract infections in pregnant women.

Immunological reactivity of animals with tuberculosis under the influence of ionising radiation

Effective control of animal tuberculosis is possible only with a comprehensive examination of the biology of the pathogen, epizootiology, pathogenesis, prevention methods, economic and environmental factors that affect the course of the disease. It is known that radiation exposure leads to autosensitisation of the body by the breakdown products of its tissues and the development of non-specific (false) immunological reactions. Therefore, the purpose of the study was to examine the immunological (serological) reactivity of tuberculosis patients exposed to gamma radiation in laboratory animals. Radiological, bacteriological, allergic, serological, and pathoanatomical research methods were used in the study. Guinea pigs were consistently irradiated with various doses of gamma rays, infected with Mycobacterium tuberculosis of various types, and, for 90 days, were examined by clinical, allergic, pathoanatomical, and serological methods in the complement fixation reaction (CFR) and passive hemagglutination reaction (PHGR) according to Boyden to detect antitubercular complementbinding antibodies and tissue autoantibodies. 45 and 90 days after infection with M. bovis and M. tuberculosis antitubercular complement-binding antibodies were recorded in serum samples of irradiated and non-irradiated animals in diagnostic titres (1:20-1:80), which indicates the active development of the infectious process. In irradiated and intact guinea pigs infected with M. avium, no anti-tuberculosis antibodies were detected in since guinea pigs are not susceptible to infection with the causative agent of avian tuberculosis. In serum samples from uninfected guinea pigs, both irradiated and intact, antitubercular complement-binding antibodies were not detected during the entire follow-up period (90 days). The high content of tissue autoantibodies in blood serum samples of animals irradiated with a dose of 200 R (0.0516 C/kg) is a manifestation of autosensitisation of the body by the breakdown products of its tissues due to radiation damage. The presence of tissue autoantibodies in blood serum samples of irradiated and Mycobacterium-infected animals did not affect serological indicators for the indication of anti-tuberculosis antibodies, which should be considered when conducting diagnostic studies by veterinary medicine laboratories

Bioprofiles of <i>Staphylococcus spp.</i> isolated from prostate secretion in men with chronic bacterial prostatitis

Objective. To characterize pathogenic pheno- and genoprofiles of staphylococci of different species, isolated from the secretion of the prostate gland in male patients with chronic bacterial prostatitis.Materials and methods. The bacterial spectrum of microflora was studied by a bacteriological method; the species identification of microorganisms was carried out by mass spectrometry. Detection of genes determining pathogenicity factors was carried out by PCR. The biofilm-forming ability of staphylococci, as well as their anti-lysozyme, hemolytic, and adhesive activity, were determined by photometry.Results. Staphylococci were found to be dominant in the pathogen structure of chronic bacterial prostatitis. These microorganisms, regardless of their species, had a pronounced pathogenic potential. Specific features in the bioprofiles of cultures of different species were determined according to the severity of the studied biological properties. Thus, the hemolytic activity and biofilm-forming ability was significantly higher in S. aureus. Conversely, CNS strains were characterized by high anti-lysozyme activity. A significant difference was noted in the prevalence of genes that determine pathogenicity factors in the studied staphylococci of different species.Conclusion. The pathogenic bioprofile of staphylococci of various species isolated from patients with chronic bacterial prostatitis can be used as a criterion in the search and identification of the pathogen, as well as in the development of effective therapeutical approaches.

Databases of the evolution of the microbiome and its drug susceptibility in astronauts and hermetic facility operators

When planning lunar bases and during long-term interplanetary (autonomous) flights, the issue of accumulation of pathogenic microbiota in conditions of closed inhabited objects is relevant. This question can be answered on the basis of a long observation period. When conducting microbiological examinations on the International Space Station, it was shown that one of the main features of the human-microorganisms ecological system in the environment of manned spacecraft is the periodic accumulation of the pathogenicity potential of microorganisms. These results were confirmed in isolation ground experiments and in the analysis of the SALYUT-6, 7 and MIR, International Space Station missions. Our work presents databases of microbiota and its antibiotic resistance of cosmonauts and hermetic facility operators at various stages of space flight, or isolation experiments. The databases are designed to assess the evolution of the population of microorganisms and their antibiotic resistance in various parts of the body of cosmonauts and operators of hermetic objects before, during and after a space flight and isolation experiments. Information about the microbiome of astronauts has been streamlined and entered into the database since 1970. The databases contain information about the microbiota in chronological order and its antibiotic resistance in cosmonauts and pressurized facility operators. Samples of various parts of the body were analyzed: forehead, chest, neck, ear, arm, armpit, groin, intestines, plaque, oral cavity, pharynx, tongue, nose, cheeks. Experimental samples of microbiota obtained from the International Space Station are stored at a deep freeze of -76 °С, are examined using a standard bacteriological method, molecular biology research methods and immunochemical methods. The information obtained makes it possible to assess the normal and dysbiotic state of the cosmonauts' microbiota. The databases are constantly updated. Thanks to the adapted database format, it is possible to use neural network and BIG DATA methods for analysis.

Antibiotic resistance pattern of Salmonella typhi in patients attending a teaching hospital in Bangladesh

Enteric fever or typhoid is caused by the human-specific gram-negative pathogen Salmonella enterica serovar typhi (S. typhi). The incidence of typhoid fever remains high in rural areas and the emergence of multidrug resistance has exacerbated the situation. The present study examined the antimicrobial susceptibility patterns of Salmonella typhi to the antibiotics commonly used in Bangladesh. This study also examined the status of prescription antibiotic use. From July 2016 to June 2017, a total of 40 bacterial pathogens were isolated from blood samples from 100 clinically suspected patients at a teaching hospital in Savar, Dhaka. The blood samples were subjected to analysis byWidal test, microscopy, culture and susceptibility testing using conventional bacteriological methods. A total of 40% of cases had an established bacterial etiology with S. typhi. The highest antimicrobial susceptibility to S. typhi was observed for meropenem (77.5%), gentamicin and imipenem (72.5%), and cefotaxime (70%), respectively. The maximum resistance was observed in the penicillin group, such as (80%) followed by cotrimoxazole (75%). Carbapenem-type beta-lactam antibiotics (meropenem, imipenem) and third-generation cephalosporins (cefotaxime, ceftriaxone, and ceftazidime) were the most effective drugs for typhoid fever. Prescription survey results in four cities in Bangladesh showed that typhoid patients were mainly prescribed third-generation cephalosporins such as cefixime (36.73%) and ceftriaxone (18.37%). The findings are important for an adequate identification of the pathogens and their antibiotic resistance for the correct selection of antibiotics in typhoid fever. The study has implications for the development of guidelines for prescribing antibiotics for typhoid fever in Bangladesh.
 Jahangirnagar University J. Biol. Sci. 11(1 & 2): 69-79, 2022 (June & December)

Resistance to antibacterial drugs and bacteriophages of Klebsiella pneumoniae isolates isolated from children of different ages with intestinal infections

The aim is to study the antibiotic and phage resistance of K. pneumoniae strains isolated from children with acute intestinal infections. Materials and methods . 490 K. pneumoniae strains isolated by the bacteriological method from feces from patients with intestinal infections of various etiologies aged from 1 month to 18 years in the period 2019—2021 were studied. The diagnosis of intestinal infection caused by K. pneumoniae was established taking into account the detection of the pathogen at a concentration of at least 5 lg CFU/g (n = 283; 57.8%). Children with Klebsiella seeding, made up three age groups: from 1 to 12 months of life (n = 245; 50%); from 1 to 3 years (n = 131; 26.7%); from 3 to 18 years (n = 114; 23.3%). Results . A higher frequency of K. pneumoniae seeding in high concentrations from fecal samples of children with intestinal infections aged from 1 to 12 months was established (?2 = 14.24; p < 0.001). Analysis of the frequency of K. pneumoniae resistance to antimicrobials revealed its increase to ampicillin/sulbactam from 4.2 ± 1.6% to 9.7 ± 1.9% and to gentamicin from 3.0 ± 1.3% to 7.6 ± 1.7% (p < 0.05) with an increase in the concentration of the pathogen from 3—4 to 5—6 lg CFU/ml. In K. pneumoniae strains isolated in low concentrations, resistance to polyvalent anti-klebsiella bacteriophage was significantly higher than to monovalent bacteriophage. Conclusion . Children of the first year of life belong to the risk group for the development of klebsiella intestinal infection. An increase in the frequency of K. pneumoniae resistance to ampicillin/sulbactam and gentamicin correlates with an increase in the concentration of the pathogen in fecal samples.

Comparative Analysis of Methods of Environmental Surface Sampling for Assessment of Viral and Bacterial Contamination

Introduction: One of the key elements of the infectious disease surveillance system is microbiological monitoring of contamination of environmental objects and health care personnel hands. In the context of the COVID-19 pandemic, virology testing of swabs from hospital objects and personal protective equipment of workers of infectious disease hospitals for patients with COVID-19 has acquired special importance. According to the current regulatory documents, however, greater priority in microbiological monitoring is given to determination and identification of bacterial pathogens, thus necessitating the development and implementation of an advanced technique of a simultaneous assessment of viral and bacterial contamination. Objective: To compare different environmental surface sampling techniques used to assess viral and bacterial contamination. Materials and methods: Samples for environmental swab testing were collected in accordance with the “Scheme for sampling environmental swabs for simultaneous assessment of viral and bacterial contamination” patented by the authors (Industrial Design Patent No. 132971 of September 5, 2022). We applied bacteriological, molecular genetic, and statistical methods in the study. Results: Overall, 343 wipe samples were tested, of which 68 were atypical (two 38-swab portions, 11.1 % each, contained SARS-CoV-2 RNA and opportunistic microorganisms). Among the opportunistic microorganisms, 42 bacterial strains were identified, including 16 strains of Enterococcus faecalis (38.1 %), 9 strains of Klebsiella pneumoniae (21.4 %), 7 strains of Escherichia coli (16.7 %), 3 strains of Enterococcus faecium (7.1 %), 3 strains of Staphylococcus aureus (7.1 %), 2 strains of Pseudomonas aeruginosa (4.9 %), and 2 strains of Pantoea agglomerans (4.9 %). Eleven variants of viral and bacterial associations were identified. The comparison of environmental swabbing performed by the technique under study with that performed by the standard method, based on test results, indicated a significant 11.1 and 12.3-fold difference in the proportion of non-standard findings for SARS-CoV-2 and opportunistic microorganisms, respectively. Conclusions: The study results prove that our technique of environmental swabbing meets all modern requirements and facilitates an objective assessment of the level of viral and bacterial contamination of the study objects. This approach can be used for laboratory testing within state and industrial control at institutions of various specialties (healthcare, food industry, childcare facilities, etc.).

Characteristics of the intestinal microflora in children receiving anti-tuberculosis therapy

The progress in investigating microbiome in children and adolescents as well as its impact on maintaining health is considered one of the most significant achievements of modern medicine. In children with various diseases, the qualitative and quantitative indicators of the intestinal microflora change, which causes the development of dysbiosis. The assessing changes in intestinal microflora in children during treatment with anti- tuberculosis drugs has retained its importance and relevance due to insufficient data in the field, which requires a more detailed understanding of this problem. The presented article assesses the state of gut microbial biocenosis in children receiving anti-tuberculosis treatment. The purpose of the study: to study the microbial landscape of the colonic contents in children receiving anti-tuberculosis therapy. Materials and methods. The study included 24 children with verified tuberculosis of the respiratory organs receiving treatment in a 24-hour hospital of the Kuzbass Clinical Phthisiopulmonological Medical Center named after I.F. Kopylova. The study of intestinal microflora was carried out by a quantitative bacteriological method. The material of the study was feces collected in a sterile disposable container, which was delivered to the Department of Microbiology, Immunology and Virology of the Federal State Budgetary Educational Institution of the Russian Ministry of Health. Results. Dysbiosis with predominance of microecological disorders of II (41.7%) and III (37.3%) degrees was detected in all children receiving anti-tuberculosis therapy. The microbial landscape of the intestine was characterized by a decrease in the quantitative content of representatives of the obligate flora Bifidobacterium spp. in 66.7% of children and Lactobacillus spp. in 45.8%, an increase in the number of facultative microorganisms: E. coli lac+ and Citrobacter freundii in 12.5%. Maintaining a full-fledged and active intestinal normobiota is possible by ensuring its dynamic control in children with tuberculosis during treatment. The results of studying the characteristics of the microbiota suggest that patients need probiotic therapy during the treatment of tuberculosis. Conclusion. Microecological disorders in children with tuberculosis therapy were characterized by a decrease in the quantitative content of representatives of obligate flora and an increase in the number of facultative microorganisms. Also in the material, various types of fungi of the genus Candida were identified.

Nitrofurantoin Sensitivity among Escherichia coli and Gram-Positive Cocci Isolated from Urinary Tract Infection

BACKGROUND: Urine samples constitute a major proportion of the samples tested in routine diagnostic laboratories. Nitrofurination used to treat urinary tract infection (UTI) for both Gram-positive and negative bacteria. Resistance to UTI is growing with time, so continuous evaluation of antibiotic is urgent. MATERIALS AND METHODS: Mid-stream urine samples were collected from patients suspected with UTI. All these samples were inoculated on culture media aerobically at 37°C for overnight. A total of 100 bacteria of both Escherichia coli and Gram-positive cocci were diagnosed by general diagnostic bacteriological methods. Disc diffusion method used for antibiotic sensitivity test; two discs were tested, nitrofurination 300 μg and ceftazidime 30 μg. All the statistical analyses were done using SPSS 26 software and the Excel app. RESULTS: From the total of 100-positive specimens, the female was high prevalence with 72 specimens (72%), whereas males were just 28 specimens (28%) significantly (P < 0.0001). Nitrofurination was very sensitive in E. coli at 90.6% compared to G+ cocci at 33.3% (P < 0.0001). Ceftazidime showed no differences between E. coli 28.1% and G+ cocci 27.8% (P = 0.97). CONCLUSION: Nitrofurination is effective in both E. coli and G+ ve cocci, but it is more effective against Gram-negative bacteria (E. coli) 90.6% than G+ ve cocci 33.3% significantly (P < 0.0001). There is no significant correlation between ceftazidime and nitrofurantoin (r = −0.07, P = 0.44).

Environmental contamination across multiple hospital departments with multidrug-resistant bacteria pose an elevated risk of healthcare-associated infections in Kenyan hospitals

BackgroundHealthcare-associated infections (HAIs) are often caused by multidrug-resistant (MDR) bacteria contaminating hospital environments which can cause outbreaks as well as sporadic transmission.MethodsThis study systematically sampled and utilized standard bacteriological culture methods to determine the numbers and types of MDR Enterococcus faecalis/faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species, and Escherichia coli (ESKAPEE) from high-touch environments of five Kenyan hospitals; level 6 and 5 hospitals (A, B, and C), and level 4 hospitals (D and E), in 2018. Six hundred and seventeen high-touch surfaces across six hospital departments; surgical, general, maternity, newborn, outpatient and pediatric were sampled.Results78/617 (12.6%) of the sampled high-touch surfaces were contaminated with MDR ESKAPEE; A. baumannii, 23/617 (3.7%), K. pneumoniae, 22/617 (3.6%), Enterobacter species, 19/617 (3.1%), methicillin resistant S. aureus (MRSA), 5/617 (0.8%), E. coli, 5/617 (0.8%), P. aeruginosa, 2/617 (0.3%), and E. faecalis and faecium, 2/617 (0.3%). Items found in patient areas, such as beddings, newborn incubators, baby cots, and sinks were the most frequently contaminated. Level 6 and 5 hospitals, B, 21/122 (17.2%), A, 21/122 (17.2%), and C, 18/136 (13.2%), were more frequently contaminated with MDR ESKAPEE than level 4 hospitals; D, 6/101 (5.9%), and E, 8/131 (6.1%). All the sampled hospital departments were contaminated with MDR ESKAPEE, with high levels observed in newborn, surgical and maternity. All the A. baumannii, Enterobacter species, and K. pneumoniae isolates were non-susceptible to piperacillin, ceftriaxone and cefepime. 22/23 (95.6%) of the A. baumannii isolates were non-susceptible to meropenem. In addition, 5 K. pneumoniae isolates were resistant to all the antibiotics tested except for colistin.ConclusionThe presence of MDR ESKAPEE across all the hospitals demonstrated gaps in infection prevention practices (IPCs) that should be addressed. Non-susceptibility to last-line antibiotics such as meropenem threatens the ability to treat infections.

Extrapulmonary tuberculosis: diagnostic features

Objective. To study demographic, clinical characteristics and concomitant pathology of patients with extrapulmonary tuberculosis (EPTB) in Gomel city and Gomel region for the period 2017-2021. To evaluate the informative value of different techniques for the detection of Mycobacterium tuberculosis (MBT) in non-respiratory samples in the diagnosis of extrapulmonary tuberculosis.Materials and methods. A retrospective study of extrapulmonary tuberculosis cases registered from 2017 to 2021 in Gomel and Gomel region (308 patients) was carried out. The results of microscopic, bacteriological and molecular genetic methods of non-respiratory and respiratory samples relevant in the diagnosis of extrapulmonary forms of tuberculosis were analyzed.Results. Demographic and clinical characteristics of patients with EPTB in Gomel and Gomel region for the period 20172021 were revealed. Concomitant pathology in patients with EPTB was analyzed, the features of EPTB diagnostics were studied. It was determined that EPTB is more susceptible to males aged 31 to 50 years and to women aged over 60 years. EPTB is more frequently diagnosed in patients from urban areas and when patients come to medical institutions with nonspecific complaints, except for intrathoracic lymph node tuberculosis (ITLN).Conclusion. In the structure of clinical forms of EPTB, lesions of bones and joints (62.7%) and intrathoracic lymph nodes (19.5%) predominate. HIV-positive patients are more common in the ITLN group. MBT is most often detected in the following localizations of extrapulmonary process: intrathoracic and peripheral lymph nodes, pleural tuberculosis. The most highly informative method of examination of biological nonrespiratory material for detection of MBT in extrapulmonary localization is molecular genetic study.

Antibiogram Pattern of Multidrug Resistance of Gram-negative Extended Betalactamase Isolates from Urine of Diabetic Patients

Background: The rate of multidrug resistant bacteria is the most worrisome in the health setting because it often associates with nosocomial infection. Objectives: This present study aim at, evaluating the antibiotic pattern of multidrug resistance of Gram-negative extended betalactamase isolates from urine of diabetic patients. Methods: This is a cross sectional study carried out at Nnamdi Azikiwe University Teaching Hospital with a total of 110 diabetic patients and were recruited using convenient sample method. The patients were instructed on how to collect the mid-stream urine samples without contamination. The samples were cultured and characterized the isolates following standard bacteriological methods. The isolated bacteria were subjected to sensitivity test pattern using agar disc diffusion techniques. The multidrug resistant isolates were physically checked for the extended spectrum betalactamase production. Obtained data was subjected to these statistical tools; descriptive statistics, chi-square and pair-test using Statistical Package for the Social Science (SPSS version 26). Results: Out of 110 urine samples assessed for significant growth of bacteria, it was found that, 55(27%) were the Gram negative bacteria (GNB).The highest prevalence of isolates were E. coli 30(54.6%), followed by Klebsiella pneumonia 14 (25.5%), Pseudomonas aeruginosa 6 (10.9%), and Proteus species 5 (9.09%) respectively. The most occurrence of the MDR bacteria were found in Augmentin 46 (83.6%) as well as as Cefuroxime 43 (78.2%) respectively. The significant mean range of Augumentin and Cefixime resistant to ESBL producers were (0.53±1.2; p = 0.000) and (0.600 ± 0.974; p = 000) respectively. Conclusion: The study detected the high proportion of multi-drug resistant isolates and the most occurrence were found in E. coli and Klebsiella pneumoniae. Regular monitoring, conducting, supervising, or management of antibiotics and molecular biomarkers for drug resistance are paramount to curtail the rate of drug-resistant pathogens.

Will E. coli retain its leading position as a causative agent of urinary tract infection in children?

Introduction. According to information from various literature sources, Escherichia coli is the most common (80–90%) causative agent of urinary tract infection (UTI) in children, it also significantly exceeds the frequency of occurrence of other bacteria, although there is a tendency to gradually decrease its specific gravity, especially against the background of other pathogens of the intestinal group.Aim. To determine the specific gravity of E. coli as the causative agent of UTI, depending on age against the background of other pathogens.Materials and methods. The study involved 133 children aged 1–17 years with UTI, girls – 107, boys – 26. The bacteriological method determined the pathogen, its sensitivity to standard antibiotics and the ability to produce extended-spectrum beta-lactamases (ESBL). Statistical processing was carried out in the Excel program. In the statistical study of the conjugacy of the signs age and infection, the Kruskal – Wallis criterion was used. Patients are grouped into the following age categories: 1–3, 4–7, 8–11, 12–14 and 15–17 years.Results. The authors of the article provided information that E. coli, although it is the leader, but its share is not as large as is commonly believed and is only 26–29%, while 18% of the total are producers of ESBL. The article shows the distribution of UTI pathogens by age groups of children and calculates the empirical probability of detecting various pathogens at different ages. It is shown that the age group of 8–11 years is most susceptible to mixed infection. According to the structure of mixed infections, these are combinations of pathogens of the intestinal group: E. coli with E. faecalis or E. faecium or with Klebsiella pneumoniae.Conclusions. The authors raised the question of the need in the near future to correct the schemes of empirical antibacterial therapy in connection with the excess of the justified 10–20% resistance of E. coli to cephalosporins of the 3rd generation due to an increase in the frequency of ESBL production.

Using dot-immunoassay in decoding the outbreak of pseudotuberculosis in the Tomsk region

Background. Pseudotuberculosis remains a serious healthcare problem, which determines the expediency of developing the express methods for its early diagnosis. To detect the pathogen, we designed test system for dot-immunoassay (DIA) based on antibodies labeled with silver nanoparticles (SNPs) isolated from hyperimmune rabbit serum obtained against killed cells of Yersinia pseudotuberculosis of O:1b serovariant.The aim. To assess the possibility of using dot-immunoassay for express identification of Y. pseudotuberculosis cultures isolated from clinical material and environmental objects at the initial stage of bacteriological study during laboratory diagnosis of the disease.Methods. We used the materials from the outbreak of pseudotuberculosis in the Krylovskaya Boarding School of the Bakcharsky district of the Tomsk region in 2021. Specific antibodies from hyperimmune rabbit sera obtained against Y. pseudotuberculosis 3704 particulate antigen of O:1b serotype were labeled with SNPs and used in DIA on nitrocellulose membranes with visualization of reaction results with a solution of a physical developer. The presence of the causative agent of pseudotuberculosis in the test material was inferred by the formation of gray spots of different intensity (from 4+ to 1+).Results. All Y. pseudotuberculosis strains isolated using bacteriological method on the second day of the study from clinical material obtained from sick people and environmental objects were detected in DIA at concentrations ≥ 3.1 × 104 microbial cells per milliliter (m.c./ml).Conclusion. The designed test system for dot-immunoassay using SNPs as a marker of specific antibodies for the detection of Y. pseudotuberculosis in cultures isolated from swabs from vegetables and clinical material from patients, including those with mixed infection, allows us to detect a specific corpuscular antigen with a high sensitivity (≥ 3.1 × 104 m.c./ml), providing express identification of isolated cultures at the initial stage of bacteriological study.

Isolation of Pathogenic Bacteria from Equipment of the Care Units, Hands and Mobile Devices for Medical Staff in Educational Al-Hussein Hospital

Bacterial contamination of intensive care units is of medical concern because it is one of the large risk factors of ICU -acquired infections and centre point of multi-drug resistant pathogens . Cell phones are important source of the microbial transmission as human pathogens also may be cause increased risk for incidence of bacterial infections as well as natural microbiota of human skin .The aim of this study to isolate and diagnose bacteria from intensive care units and mobile devices for medical staff in these units at Educational Al -Hussein Hospital In the city of Nasiriyah. Collection of samples from teaching Al-Hussein hospital, the number of samples 100 distributed Between Swabs of mobiles(30) teaching Al-Hussein hospital medical staffs and ( 50) from hands of nursing and worker and Technicians and doctor Stethoscope also collecting samples(20) swab from department of ICU (Intensive care unit),CCU (Critical care unit), RCU (Respiratory care unit) collect the samples from medical equipment in care unit (ECG (Electro cardio graph), DC- Shock, Suction Device (sucker) , Monitor Device and Ventilator Device )analyzed by standard Bacteriological methods. The frequency pathogenic bacteria obtained in clinical isolates from the sections was 60 out of 20 swab. The maximum frequency of E. coli is 15 isolates by (25)%, most of them in Ventilator Device, The lowest frequency was for Staphylococcus epidermitis with 3 isolates by (5)%, mostly in Suction unit(sucker)and The positive culture was (32) which is more than negative culture(18) out of 50 swabs, But higher positive culture found in a stethoscope with 8 isolates (25)% followed by in hands of technician , Workers , with 7 isolates (21.8)% Respectively as well as highest number and percentage of bacterial contaminated on phone of medical and health staffs were E.coli, Enterococcus faecalis(16.3 ) % Respectively followed by Staphylococci aureus (14.5%), and Klebsiella pneumonia (12.7%) .bacterial cultures found at higher rate among age groups (31-40) years by 56.3%. But the female showed higher rate of bacterial cultures compares to males by 56.2% . Keywords: intensive care units( ICU ) , Bacterial contamination , E.coli , Hospital

Character of wound microflora and resistance to antibiotics: monitoring results 2012–2020

The aim of the study was to improve the microbiological diagnosis of surgical infections, collect and analyze the data on the spectrum of surgical microflora and monitoring of antibiotic resistance in the period from 2012 to 2020.The research material was the separation of surgical wounds of patients, cultures of gram-negative and gram-positive bacteria isolated from the biological material of patients by the bacteriological method, the results of testing the sensitivity of bacterial cultures to antibiotics by diffusion into agar and using semi-automatic analyzers VITEK-2.A 9-year multicenter monitoring of the species composition of bacteria associated with wound infections revealed a high frequency of isolation of a number of conditionally pathogenic microorganisms – Escherichia spp., Klebsiella spp., Pseudomonas spp., Acinetobacter spp., Enterococcus spp., Streptococcus spp., Staphylococcus spp., Citrobacter spp., Proteus spp. In the period from 2012 to 2020, the amount of information entered into the computer database about these bacterial strains increased 1.4–2.0 times. Monitoring of bacterial resistance to antibiotics during this period showed a high level and dynamics to 3rd generation cephalosporins, carbapenems, and other classes. The lowest levels of resistance were found among the strains of Escherichia and the highest – Klebsiella, Pseudomonas and Acinetobacter. Staphylococci are characterized by high percentage of methicillin-resistant strains.Gram-negative (Escherichia, Klebsiella, Pseudomonas, Acinetobacter) and gram-positive (Enterococci, Streptococci, Staphylococci) are detected in the surgical patients with UTI with a high frequency. Surgical pathogens are characterized by a high level of resistance to 3rd generation cephalosporin, carbapenems, and other antibiotics. Long-term monitoring of bacterial resistance to antibiotics makes it possible to increase the effectiveness of laboratory diagnostics of surgical infections, to assess a resistance level of pathogens, an antibacterial therapy strategy and a medical aid quality.

Экспериментальная оценка в опытах in vitro и in vivo чувствительности бактерий Yersinia pseudotuberculosis к антимикробным композициям на основе наночастиц меди

The paper presents the results of the antibacterial efficacy of disinfecting compositions based on copper nanoparticles and its oxides in antiseptic solutions of cetylpyridinium chloride and benzalkonium chloride against the causative agent of pseudotuberculosis Y. pseudotuberculosis of in vitro and in vivo experiments. Using the bacteriological method and the results of electron microscopy, high bactericidal activity of disinfecting compositions has been proven. Anti-yersiniosis activity and safety of both compositions were revealed in experimental pseudotuberculosis of conventional white mice. Simultaneous oral administration of the compositions under study to experimental animals limits the initiation and development of the infectious process and prevents the death of laboratory animals. Possible mechanisms of enhancing the biocidal activity of the tested disinfecting compositions are considered. Keywords: pseudotuberculosis, microorganisms, biocidal activity, antiseptic, nanoparticles, zeta potential.

Prevalence and Biological Characteristics of Listeria Species Isolated from Livestock and Poultry Meat in Gansu Province, China.

Listeria monocytogenes is a widespread foodborne pathogen contaminating foods during their production or processing stages. Fresh meat is susceptible to such contamination if it is not properly preserved. Our study was conducted to reveal the level of contamination and prevalence of Listeria spp. present in livestock and poultry meat from Gansu province. A total of 1,387 samples were collected from five cities in Gansu Province according to standard sampling procedures, of which 174 samples (12.5%) were positive for Listeria species. Among them, 14 isolates of L. monocytogenes (1.0%), 150 isolates of Listeria innocua (10.8%), and ten isolates of Listeria welshimeri (0.7%) were identified by conventional bacteriological and molecular identification methods. All isolates were subjected to serological assays, antimicrobial susceptibility tests, growth curve assays, determination of biofilm-forming capacity, and cluster analysis of the 16S rRNA gene sequences. Four predominant serotypes of L. monocytogenes were identified, including 1/2a (35.7%, 5/14), 1/2b (14.3%, 2/14), 1/2c (42.9%, 6/14), and 4b (7.1%, 1/14). All L. monocytogenes isolates were resistant to tetracycline and cefoxitin. Most L. innocua isolates (63.6%, 14/22) and L. welshimeri (40%, 4/10) were resistant to tetracycline. The high biofilm-forming ability was observed among 1/2c and 1/2a serotype isolates. The cluster analysis of the 16S rRNA gene sequences revealed a close genetic relationship between the three Listeria species. This study fills the gap in the knowledge of livestock and poultry meat that carry Listeria in slaughterhouses and markets in Gansu Province.

Etiological Structure of Leptospira interrogans in Natural Foci of the Baikal Region

Introduction: Studying the functioning of natural foci of leptospirosis, analyzing the structure of pathogens and the species composition of animal carriers are important parts of assessing the current epizootic situation in natural foci, necessary for planning and organizing anti-epidemic measures, including specific prevention of this bacterial disease. Objective: To establish Leptospira interrogans serogroups in natural foci in the Baikal Region. Materials and methods: In 2011–2021, we conducted zoological surveys of the territories of the Irkutsk Region within the borders of 10 administrative districts. In total, 1,255 small mammals of 36 species were caught in their natural habitats in accordance with the guidelines of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing (Rospotrebnadzor). The animals belonged to five orders, including rodents (Rodentia) – 74.2 %, insectivores (Eulipotyphla) – 24.7 %, hares (Lagomorpha) – 0.6 %, predators (Carnivora) – 0.4 %, and bats (Chiroptera) – 0.2 %. Samples collected from the animals were tested using bacteriology, microscopy, and serology methods. Results: Of all the samples collected, 2.3 % gave a positive test result for Leptospira interrogans. Its main carriers in the Baikal Region were representatives of the order of insectivores: tundra borer (Sorex tundrensis Merriam, 1900) and rodents: housekeeper vole (Alexandromys oeconomus Pallas, 1776), water vole (Arvicola amphibius Linnaeus, 1758), long-tailed ground squirrel (Urocitellus undulatus Pallas, 1779), muskrat (Ondatra zibethicus Linnaeus, 1766), and narrowcrusted vole (Lasiopodomys gregalis Pallas, 1779). The serogroups detected included Icterohaemorrhagiae, Grippotyphosa, Javanica, Australis, Pomona, Sejroe, Autumnalis, with the antibody titers ranging from 1:20 to 1:640. Conclusions: Natural foci of leptospirosis are widespread in the Baikal Region. Compared with the results of studies conducted in the 20th century, the relative number of seropositive animals has increased slightly while the landscape of Leptospira serotypes has undergone changes.

Postpasteurization Testing of Human Milk Sterility at Human Milk Banks in Resource-Limited Settings: An Alternative to Standard Microbiological Quality Testing.

Introduction: Pasteurized donor human milk provides nutrition and bioactive factors for infant growth and health when a mother's own milk is not available. Bacteriological testing is recommended for each pasteurized batch of donor milk before distribution to ensure that the milk is safe for use. Charm Peel Plates (CPPs) are a simplified, easy-to-use culture method for detecting microorganisms in milk and milk products. This study investigates the feasibility of using CPPs as an alternative test for current standard postpasteurization screening by human milk banks (HMBs), particularly those in resource-limited settings. Aim: The aim of this study was to evaluate the feasibility of using the CPP versus the 5% horse blood agar (HBA) plate (standard South African National Health Laboratory Service method) for detecting bacterial growth in pasteurized human milk samples. Methods: For each of the 50 pasteurized donor milk samples, 100-μL aliquots were cultured on routine HBA and 1 mL on CPPs for the total bacterial colony count. Any positive growth was identified using VITEK® 2 (bioMérieux). To demonstrate the ability of CPPs to support bacterial growth, four spiked samples were tested. Results: Concurrent negative test results were reported for 49/50 (98%) samples with only one positive test with HBA. Conclusions and Recommendations: The CPP is equivalent to HBA for detection of bacterial growth. Additional advantages of CPPs are ease of use and cost-effectiveness. The CPP is therefore recommended as a point-of-care, bacteriological screening method for donor human milk by HMBs, particularly those in resource-limited settings.