Staphylococcal Strains Research Articles

Protein-Energy Malnutrition as a Predictor of Early Recurrent Revisions After Debridement Surgery in Patients With Difficult-to-Treat Periprosthetic Infection

Background. Protein-energy malnutrition (PEM) is an established risk factor of postoperative complications in orthopedic disorders, including arthroplasty of the large joints.
 The study aimed to evaluate PEM prevalence and its association with the early postoperative revision in patients with the difficult-to-treat (DTT) prosthetic joint infection (PJI) of the hip.
 Methods. The retrospective study included 132 patients with chronic DTT PJI of the hip. The patients underwent orthopedic implant removal, radical debridement of the infected tissues, and resection arthroplasty with non-free transplantation of an axial vastus lateralis muscle flap (n = 57) or installation of an antimicrobial spacer (n = 75). DTT PJI was defined as an infection caused by rifampicin-resistant staphylococcal strains, ciprofloxacin-resistant gram-negative bacteria, fungi of the genus Candida, and their associations. The assessment of the patients protein-energy status included the evaluation of reference laboratory parameters, such as levels of hemoglobin, total protein, and albumin and number of lymphocytes. The degree of PEM was determined by the number of laboratory markers below the threshold values. The statistical comparison was performed using Fishers test. The odds ratio (OR, 95% confidence interval [CI]) was calculated to assess the risk of PJI recurrence. Differences were considered significant at p0.05.
 Results. More than 70% of patients with chronic DTT PJI included in the study were diagnosed with preoperative PEM of varying degrees of severity. Hypoalbuminemia and decreased hemoglobin levels were diagnosed more often: 64.3% and 57.1% in the muscle flap plasty and 57.3% and 31.1% in the antimicrobial spacer group, respectively. In muscle plasty and antimicrobial spacer groups, a decrease in the values of three or more reference PEM markers was detected in 28.5% and 16.0% of patients, and this advanced impairment of the nutritional status increased the risk of early revision intervention by two (OR 2.0; CI 95% 0.478.56; p = 0.35) and six times (OR 6.11; 95% CI 1.0635.35; p0.04), respectively.
 Conclusion. In general, the analysis of publications and results of our study show that PEM is associated with the development of surgical site infection and recurrence of PJI after revision surgery. A decrease in the values of three or more reference PEM markers is a significant predictor of repeated revisions after debridement surgery with the installation of an antimicrobial spacer. PEM complicates the postoperative course in patients with resection arthroplasty. Given the high incidence of PEM in patients with DTT PJI of the hip joint, further research is needed to develop methods for nutritional status correction and assessment of their effect on the outcomes of debridement surgery.

Rifabutin versus rifampicin bactericidal and antibiofilm activities against clinical strains of Staphylococcus spp. isolated from bone and joint infections

Staphylococci account for approximately 60% of periprosthetic joint infections (PJIs). Rifampicin (RMP) combination therapy is generally considered to be the treatment of choice for staphylococcal PJIs but carries an important risk of adverse events and drug-drug interactions. Rifabutin (RFB) shares many of the properties of rifampicin but causes fewer adverse events. To compare the minimal inhibitory concentration (MIC), the minimum bactericidal concentrations (MBC), and the minimum biofilm eradication concentrations (MBEC) of rifabutin and rifampicin for staphylococcal clinical strains isolated from PJIs. 132 clinical strains of rifampicin-susceptible staphylococci [51 Staphylococcus aureus (SA), 48 Staphylococcus epidermidis (SE) and 33 other coagulase-negative staphylococci (CoNS)] were studied. The MBC and the MBEC were determined using the MBEC® Assay for rifabutin and rifampicin and were compared. When compared with the rifampicin MIC median value, the rifabutin MIC median value was significantly higher for SA (P < 0.05), but there was no statistically significant difference for SE (P = 0.25) and CoNS (P = 0.29). The rifabutin MBC median value was significantly higher than that of rifampicin for SA (P = 0.003) and was lower for SE (P = 0.003) and CoNS (P = 0.03). Rifabutin MBEC median value was statistically lower than that of rifampicin for all strains tested. Using the determination of MBEC values, our study suggests that rifabutin is more effective than rifampicin against clinical strains of Staphylococcus spp. obtained from PJIs. Using MBECs instead of MICs seems to be of interest when considering biofilms. In vivo higher efficacy of rifabutin when compared with rifampicin needs to be confirmed.

Isolation, identification and probiotic properties of vaginal isolates of lactic acid bacteria of healthy slaughter cows

Relevance. The use of antibiotics to treat infections of the reproductive tract in cows can cause bacterial resistance to antibiotics and endanger human health. Potentially, preparations from representatives of the lactic acid vaginal microflora (probiotics) can be used as a biological control to reduce the use of antibiotics in animal husbandry.However, the specific composition of the vaginal lactic acid microflora of healthy dry cows and its probiotic properties remain poorly documented.Methods. The species identification of catalase-negative gram-positive isolates of bacteria forming colonies on MRS agar isolated from utero-cervical mucus of healthy lactating cows was carried out in accordance with standard procedures using a culturedependent approach, biochemical tests and tests for sugar fermentation using API50 CHL strips (bioMеrieux, France). For testing for antagonistic activity by the method of delayed antagonism against test cultures of staphylococci and Escherichia, 14 isolates were selected in accordance with typing assigned to 5 species of the genus Lactobacillus.Results. The results obtained indicate that the utero-vaginal biocenosis of healthy lactating cows is represented by microorganisms of the Lactobacillaceae family, including lactic acid enterococci and bacteria of the Leuconostocaceae family. The presence of representatives of the genera Aerococcus, Peptostreptococcus and Gardnerella vaginalis was found in the composition of the vaginal biocenosis in cows without signs of pathology of the birth canal. According to the results obtained, the vaginal population of lactic acid bacteria of the genus Lactobacillus has low or medium antagonistic activity against test cultures of indicatory strains of staphylococci and Escherichia.

Co-occurrence of cfr-mediated linezolid-resistance in ST398 LA-MRSA and non-aureus staphylococci isolated from a pig farm

Linezolid resistance, mediated by the cfr gene, which confers resistant phenotypes to phenicols, lincosamides, oxazolidinones, pleuromutilins, and streptogramin A antimicrobials, has emerged in S. aureus and non-aureus staphylococci (NAS). Moreover, due to the transferable potential via plasmids, the spread of cfr among staphylococci is of great concern. In the present study, we investigated the prevalence of cfr-mediated linezolid resistance in ST398 methicillin-resistant S. aureus (MRSA) and NAS strains isolated from a pig farm. Among the 26 staphylococci isolates collected from a pig farm, 14 cfr-harboring ST398 MRSA and NAS (S. epidermidis, S. pasteuri, S. cohnii, and S. rostri) strains were resistant to linezolid and also carried the fexA gene. Comparative genome analysis of cfr-carrying linezolid-resistant ST398 MRSA and NAS (S. pasteuri, S. cohnii, and S. epidermidis) strains revealed that the segments harboring cfr in different staphylococcal strains showed ≥ 99 % sequence identity and the corresponding region containing the cfr, fexA, and Tn558 elements were located in a 38-kb plasmid, designated pSA12 of ST398 MRSA. These observations indicate that the cfr-carrying plasmids and/or fragments may be disseminated among staphylococci in a pig farm and possibly transmitted to staphylococci of human origin, subsequently posing a threat to public health. This is the first report of the co-existence of cfr in linezolid-resistant ST398 MRSA and NAS isolated from a pig farm in South Korea.

Characteristics of Virulence Genes of Clinically Isolated Staphylococci in Jingzhou Area.

Purpose The aim of this study was to further understand the distribution characteristics of staphylococcal virulence genes in the Jingzhou area, in order to provide a basis for clinically effective treatments and prevention and control measures. Methods A total of 181 strains of staphylococci were collected from Jingzhou Hospital Affiliated to Yangtze University from April 2013 to April 2021, which were divided into the methicillin-resistant Staphylococcus aureus (MRSA) strains and the methicillin-sensitive Staphylococcus aureus (MSSA) strains and coagulase-negative staphylococci (CoNS) by an antimicrobial susceptibility test and PCR method. The 73 MRSA strains were classified by staphylococcal cassette chromosome mec (SCCmec) and Staphylococcus protein A (Spa). Sea, sec, seh, sek, seb, seq, sep, Tsst-1, clfA, clfB, fnbA, hla, hld, hlg, lukE, bbp, cna, eap, ebpS, sdrC, sdrD, sdrE, and Pvl genes were also detected in all strains. The χ2 test was used for statistical analysis for comparison between groups. Results The 181 strains of staphylococci were divided into 97 strains of MRSA, 54 strains of MSSA, and 30 strains of CoNS. 73 MRSA strains were derived from clinical specimens such as lower respiratory tract, secretions, sepsis secreted by tissue infection, urine, and hydrothorax. There were 70 strains that can be identified including SCCmec types and 15 Spa types of all strains, while the most popular types were SCCmecIII-t030 and SCCmecIV-t437 from lower respiratory tract specimens. There were four virulence genes that were detected including seb, seq, clfB, and hld in CoNS strains, while the detection rates of these four virulence genes in Staphylococcus aureus were higher than that of CoNS, and the differences were statistically significant, P < 0.05(P=0.004, P=0.001, P=0.001, P=0.001). 23 virulence genes were detected in 151 strains of Staphylococcus aureus, among which the detection rate of the Tsst-1 gene was the lowest and that of the clfB gene was the highest, and the other genes were 4.6%∼98.0%. The detection rates of sea, sek, seb, seq, sep, cna, eap, ebpS, sdrC, and sdrE virulence genes in MRSA were higher than that of MSSA, and the differences were statistically significant, P < 0.05 (P=0.001, P=0.001, , P=0.001, P=0.001, P=0.009, , P=0.019, P=0.001, , P=0.001, P=0.001, , P=0.003). Conclusion The mainly prevalent type of MRSA strains in Jingzhou is SCCmecIII-t030 in lower respiratory tract specimens. Virulence genes of Staphylococcus aureus and antibiotic drug resistance rates are also different from other regions. In this experiment, virulence genes were also detected in CoNS, suggesting that more attention should be paid to the prevention and treatment of these strains clinically.

Elimination of bacteria from semen using a combination of density gradient centrifugation and swim-up

Background: To evaluate the efficiency of bacterial clearance of different sperm preparation procedure. Methods: A total of 46 semen samples were collected in this study, each semen sample was divided into four equal parts (0.5 mL each). The first part was prepared by density-gradient centrifugation (D-group), the second part was prepared by swim-up (S-group), the third part was treated with density-gradient centrifugation combined with swim-up (D+S-group), and the fourth group was the original raw semen group (O-group) regarded as the control. After each semen preparation procedure, the O-group and suspensions were inoculated and incubated for bacterial identification and colony counting. Results: Initially only 8.7% (4/46) of samples were bacteria free. After processing, the bacterial clearance rates were 23.8% for D-group, 57.4% for S-group and 97.8% for D+S-group (p &lt; 0.001). Multiple bacterial strains were observed in 37 samples with 117 different bacterial strains in all identified in the original semen. 44.4% of the staphylococci and 89.7% of streptococci were not eliminated in D-group. In S-group, the corresponding rates were 24.4% and 35.9%. In D+S-group there were no remaining strains of staphylococci and only 2.6% of streptococci remained. After the combined procedure, the number of bacterial colonies fell dramatically after processing. Conclusion: The combined D+S protocol appears to be substantially more efficient than either method alone in eliminating bacteria from semen samples.

Antibiotic resistance of staphylococcal strains isolated from diseases of the urinary system in cats

Antibiotic resistance of staphylococcal strains isolated from diseases of the urinary system in cats

Diversity and Distribution of Staphylococcal Chromosomal Cassettes Mec (SCCmec) Types I, II and III in Coagulase-Negative Staphylococcal Strains Isolated from Surfaces and Medico-Technical Materials of the University Hospital of Abomey-Calavi/S&amp;#244;-Ava

Diversity and Distribution of Staphylococcal Chromosomal Cassettes Mec (SCCmec) Types I, II and III in Coagulase-Negative Staphylococcal Strains Isolated from Surfaces and Medico-Technical Materials of the University Hospital of Abomey-Calavi/S&amp;#244;-Ava

Staphylococcus ratti sp. nov. Isolated from a Lab Rat.

Staphylococci from the Staphylococcus intermedius-Staphylococcus hyicus species group include numerous animal pathogens and are an important reservoir of virulence and antimicrobial resistance determinants. Due to their pathogenic potential, they are possible causative agents of zoonoses in humans; therefore, it is important to address the properties of these strains. Here we used a polyphasic taxonomic approach to characterize the coagulase-negative staphylococcal strain NRL/St 03/464T, isolated from the nostrils of a healthy laboratory rat during a microbiological screening of laboratory animals. The 16S rRNA sequence, MALDI-TOF mass spectrometry and positive urea hydrolysis and beta-glucuronidase tests clearly distinguished it from closely related Staphylococcus spp. All analyses have consistently shown that the closest relative is Staphylococcus chromogenes; however, values of digital DNA-DNA hybridization <35.3% and an average nucleotide identity <81.4% confirmed that the analyzed strain is a distinct Staphylococcus species. Whole-genome sequencing and expert annotation of the genome revealed the presence of novel variable genetic elements, including two plasmids named pSR9025A and pSR9025B, prophages, genomic islands and a composite transposon that may confer selective advantages to other bacteria and enhance their survival. Based on phenotypic, phylogenetic and genomic data obtained in this study, the strain NRL/St 03/464T (= CCM 9025T = LMG 31873T = DSM 111348T) represents a novel species with the suggested name Staphylococcus ratti sp. nov.

Antimicrobial Activity of Fuller’s Earth, Turmeric, and Sandalwood against Streptococcus Mutans, Micrococci and Coagulase Negative Staphylococci -an In vitro Study

Introduction: Sandalwood powder (Santalum alba) is used if the skin is oily for removing dark spots on the skin. Sandalwood has an anti-tanning and anti-aging property. Turmeric powder (Curcuma longa) is mainly used to rejuvenate the skin. It helps to delay aging like wrinkles and also possesses other properties like antibacterial, antiseptic, and anti-inflammatory, and many other properties. Multani mitti helps the skin in many different ways like the reduction of pore size pore sizes, removing blackheads and removing whiteheads fading freckles, soothing sunburns, cleansing skin, improving blood circulation, complexion, reducing acne and blemishes, and gives a glowing effect to your skin as they contain many-particles which can inhibit various organisms.&#x0D; Materials and Methods: In this investigation, the antimicrobial viability of Turmeric, sandalwood and Multani Mutti was tested against Streptococcus mutans, Micrococci, and coagulase-negative staphylococcus. The microorganisms were filled in strong media, and culture containing stock suspensions was made and, in this way, standard strains of Streptococcus mutans, Micrococci, and Coagulase-negative staphylococci were obtained. Microorganisms were subcultured in fitting society media to affirm their virtue.&#x0D; Results: The zone of inhibition of turmeric against Streptococcus mutans is about 11mm. The zone of inhibition of turmeric against Micrococci is about 9 mm. The zone of inhibition of turmeric against Coagulase-negative staphylococci is about 13mm. There was no zone of inhibition for both sandalwood and Multani mitti for Coagulase-negative staphylococci, Streptococcus mutans, and Micrococci.&#x0D; Conclusion: The study proves the turmeric has antimicrobial potential against Coagulase-negative staphylococci, Streptococcus mutans,, and Micrococci with good prospects of development into antimicrobial face pack or face wash

Strain diversity and antibiotic-sensitivity of staphylococcus spp. Isolates from patients of multiprofile pediatric hospital in St. Petersburg, Russia

Background. Staphylocci are the leading pus-forming Gram-positive bacteria in the childrens hospitals. The prevalence of the antibiotic resistant strains among them limits therapeutic effects of infections in children.&#x0D; Aim. The research is aimed at characterizing the species of staphylococcus, which are isolated from the different clinical specimens of the patients at the clinics of Saint Petersburg State Pediatric Medical University in 2019, and analysis of their susceptibility to antimicrobial agents.&#x0D; Materials and metods. According to the clinical recommendations of 2018, susceptibility to antimicrobial drugs (AMD) was revealed in 860 strains of staphylococci determined by the disc diffusion method, which were identified by the automated analyser Vitek-2 compact.&#x0D; Results. Six species of staphylococci were represented at the hospital departments, among which Staphylococcus epidermidis prevailed in the departments of the neonate pathology department and intensive care units (63.0% and 46.2% respectively), Staphylococcus aureus is commonly found at the departments of surgery and the departments of the therapeutic profiles (61.7% and 46.2% respectively). More than a half of the staphylococci strains (63.0%) were resistant to at least one of the antimicrobial drugs. Vancomycin and line solid showed the highest activity to these staphylococci. High specific weight of multidrug resistant (MDR) bacteria (37.8%) and extensively drug resistant (XDR) strains of the phenotype (33.0%) was revealed. The level of antibiotic resistant strains was the highest in Staphylococcus haemolyticus (98.1%) and S. epidermidis (82.0%), while the specific weight of the resistant ones, MDR and XDR strains was extremely low among S. aureus (16.2%, 1.5% and 0.4 respectively), as well as in methicillin-resistant isolates (0.8%).&#x0D; Conclusions. A great variety of antibiotic resistance was revealed among the staphylococci. The prevalence of these strains in the pediatric hospitals requires constant local monitoring of the antibiotic resistant staphylococci.

Efflux Pump Mediated Antimicrobial Resistance by Staphylococci in Health-Related Environments: Challenges and the Quest for Inhibition.

The increasing emergence of antimicrobial resistance in staphylococcal bacteria is a major health threat worldwide due to significant morbidity and mortality resulting from their associated hospital- or community-acquired infections. Dramatic decrease in the discovery of new antibiotics from the pharmaceutical industry coupled with increased use of sanitisers and disinfectants due to the ongoing COVID-19 pandemic can further aggravate the problem of antimicrobial resistance. Staphylococci utilise multiple mechanisms to circumvent the effects of antimicrobials. One of these resistance mechanisms is the export of antimicrobial agents through the activity of membrane-embedded multidrug efflux pump proteins. The use of efflux pump inhibitors in combination with currently approved antimicrobials is a promising strategy to potentiate their clinical efficacy against resistant strains of staphylococci, and simultaneously reduce the selection of resistant mutants. This review presents an overview of the current knowledge of staphylococcal efflux pumps, discusses their clinical impact, and summarises compounds found in the last decade from plant and synthetic origin that have the potential to be used as adjuvants to antibiotic therapy against multidrug resistant staphylococci. Critically, future high-resolution structures of staphylococcal efflux pumps could aid in design and development of safer, more target-specific and highly potent efflux pump inhibitors to progress into clinical use.

Oxacillin (Methicillin) Resistant Staphylococci in Domestic Animals in the Czech Republic.

The aim of this study was to describe the prevalence of different Staphylococcus species isolated from pathological processes and lesions in domestic animals in the Czech Republic and to detect and describe oxacillin (methicillin)-resistant strains (MRS). During the years 2019–2020, a total of 5218 veterinary clinical samples from the Czech Republic were tested. Testing was performed by culture methods and typing by molecular phenotypic methods MALDI-TOF MS and PCR. Antimicrobial susceptibility testing of the strains was performed by the disk diffusion method. A total of 854 staphylococci strains were identified (16.37% prevalence), out of which 43 strains of 6 species of staphylococci were MRS (n = 43; 0.82% prevalence). Of the MRS strains, the most prevalent species were Staphylococcus pseudintermedius (n = 24; 0.46% prevalence) and Staphylococcus aureus (n = 7; 0.13% prevalence). Susceptibility testing showed resistance to beta-lactam antibiotics and, depending on the species, also to trimethoprim/sulfamethoxazole, gentamicin, tetracycline, erythromycin, clindamycin, and enrofloxacin. For further characterization of MRS, PCR assay for virulence factor genes was performed. Seven of the 14 target genes were observed only in S. aureus, except for the eno gene encoding laminin-binding protein, which was also detected in other staphylococci. It is necessary to emphasize the issue of correct using of antimicrobials in practice and antibiotic policy in university teaching and to create stricter legislation that would prevent the widespread use of antimicrobials in veterinary medicine, especially in livestock to reduce the emergence and spread of antimicrobial resistance.

Plastic pollution: why is it a public health problem?

Plastic pollution: why is it a public health problem?

Antibiotic Resistance and Pathogenomics of Staphylococci Circulating in Novosibirsk, Russia.

A total of 394 strains of staphylococci found in humans and pets in Novosibirsk, Siberian Russia, were characterized in terms of antibiotic resistance and corresponding genes. Two coagulase-positive and 17 coagulase-negative species were identified. The majority of isolates, with the exception of S. haemolyticus and hospital S. epidermidis isolates, were sensitive to most of the tested antibiotics, and isolates from pets displayed the lowest level of resistance. Nevertheless, methicillin-resistant (MRS) and/or multidrug-resistant (MDR) isolates were found in all prevailed species, including coagulase-negative. A set of genes corresponding to the detected resistance was identified: mecA (beta-lactam resistance), aac(6′)-Ie-aph(2″)-Ia, aph(3′)-IIIa, ant(4′)-Ia (aminoglycoside-modifying enzymes), ermA/ermC, and msrA (macrolide resistance). Complete genome analysis for ten MDR S. epidermidis and five MDR S. haemolyticus isolates revealed additional antibiotic resistance genes mphC, qacA/qacB, norA, dfrC/dfrG, lnuA, BseSR, and fosB. NorA, dfrC, and fosB were present in all S. epidermidis genomes, whereas mphC and msrA were identified in all S. haemolyticus ones. All investigated MDR S. epidermidis and four of five S. haemolyticus strains were moderate or strong biofilm producers, whereas multiple genes responsible for this function and for virulence and pathogenicity were identified mostly in S. epidermidis, but were less frequently represented in S. haemolyticus.

The prospects of finding new treatments for acne

An important role in the development of acne is played by the activity of the skin microflora (namely the bacteria Propionibacterum acnes) and members of the genus Staphylococcus. In the schemes of complex treatment of patients with this disease, antibiotics from among macrolides or lincosamides are mainly used. It is of interest to study the current state of susceptibility of staphylococci and propionic bacteria to these drugs, as well as to other antimicrobial agents in order to determine the prospects for expanding the arsenal of methods for treating acne. The aim of the study was to study the susceptibility of microorganisms involved in the development of acne to antimicrobials and antagonistic effects of probiotic strains of lactobacilli. We conducted a bacteriological study of the content of rash elements in 60 patients with acne. The biological characteristics of 40 strains of Staphylococcus spp. and 15 strains of Propionibacterum acnes isolated and researched. The sensitivity of microorganisms to antibiotics and antiseptics was determined by the disco-diffusion method and the method of serial double dilutions of drugs in a liquid nutrient medium. Determination of the sensitivity of acne pathogens to the antagonistic effect of lactobacilli was performed by the method of two-layer agar by reducing the number of microorganisms. The results of the study made it possible to establish that the isolated strains of bacteria show a low level of sensitivity to antimicrobials, which in medical practice are most often used for topical therapy of acne. Only 17.5 % of isolated staphylococcal strains were sensitive to erythromycin, only 45.0 % of strains of this species were sensitive to clindamycin. Strains of Propionibacterum acnes showed a higher level of sensitivity to antibiotics than staphylococci. However, the established indicators do not allow to consider highly effective means for treatment of acne on their basis. At the same time, a high level of sensitivity of acne pathogens to antiseptic drugs decamethoxine and Aeroplysinin 1 and antagonistic effect of Lactobacillus acidophilus was established. Thus, the strains of Propionibacterum acnes and Staphylococcus spp., involved in the development of acne, are characterized by high levels of resistance to erythromycin, clindamycin, chloramphenicol, benzoyl peroxide, which are now the basis of the arsenal of topical therapy for patients with this disease. There is a need to find new effective drugs for the etiotropic therapy of acne.

Prevalence of Staphylococcus aureus Isolated from some Street Hot Beverages in Abidjan, Côte d’Ivoire

Introduction: Staphylococcus aureus is one of the main pathogens found in street food, including hot beverages. However, information about S. aureus isolated from street hot beverages from coffee carts is very limited in Abidjan, Côte d’Ivoire.&#x0D; Aims: We aimed to characterize phenotypically S. aureus isolated from street hot beverages sold in Abidjan.&#x0D; Methodology: A total of 400 samples of hot beverage were collected and analyzed. The identification was made through conventional microbial and biochemical analysis. Macroscopic identification on the Baird Parker agar supplement with egg yolk tellurite. Microscopic observation through Gram staining as well as biochemical tests such as catalase, DNase and coagulase were performed. To confirm staphylococcal strains, the MALDI-TOF mass spectrometry was used. After identification, the susceptibility of the staphylococcal isolates was evaluated using disc diffusion method.&#x0D; Results: Result showed that most of Staphylococcus aureus (18.4%) were isolated from tea. All the strains of Staphylococcus aureus isolated from street beverages were sensitive to cefoxitin and vancomycin. All the S. aureus isolated from milk were resistant to Erythromycin. Although beverages are consumed hot, the presence of S. aureus in ready-to-drink beverage transmitted infections to consumers.&#x0D; Conclusion: This drink need attention for the seller and the user to avoid some infections.

Mechanisms of Resistance to Macrolide Antibiotics among Staphylococcus aureus.

Methicillin resistant Staphylococcus aureus strains pose a serious treatment problem because of their multi-drug resistance (MDR). In staphylococcal strains, resistance to macrolides, lincosamides, and streptogramin B (MLSB) correlates with resistance to methicillin. The rapid transmission of erm genes responsible for MLSB resistance has strongly limited the clinical application of traditional macrolides such as erythromycin. On the other hand, in the age of increasing insensitivity to antibiotics the idea of implementing a therapy based on older generation drugs brings hope that the spread of antibiotic resistance will be limited. A thorough understanding of the resistance mechanisms contributes to design of antibiotics that avoid bacterial insensitivity. This review highlights the mechanisms of action of macrolides and mechanism of resistance to these antibiotics among Staphylococcus aureus.

Clostridioides difficile and multi-drug-resistant staphylococci in free-living rodents and marsupials in parks of Belo Horizonte, Brazil.

The global emergence of antimicrobial resistance (AMR) has become a serious threat to human and animal health. Recent studies have shown that synanthropic animals can act as reservoirs and disseminators of pathogens and resistant bacteria. The aim of this study was to evaluate the frequency, distribution, and antimicrobial susceptibility of staphylococcal species and Clostridioides difficile isolated from the feces of free-living rodents and marsupials from two urban parks in Belo Horizonte, Brazil. During a 12-month period, fecal samples from 159 free-living animals, including 136 rodents and 23 marsupials, were collected from two urban parks in Belo Horizonte, Minas Gerais, Brazil. Staphylococcus spp. were more likely to be isolated from rodents than marsupials (p = 0.0164). Eight different staphylococcal species were isolated from 36 (26.5%) rodents and one marsupial (4.3%). S. saprophyticus (48.6%) was the most frequently isolated species, and almost a quarter of the isolates (24.3%) were resistant to at least one antimicrobial agent, four (10.8%) of which were multi-drug resistant (MDR). Two (5.4%) strains were resistant to cefoxitin and were then classified as methicillin-resistant staphylococci, and one also tested positive for the mecA gene. C. difficile was isolated from two rodents (1.5%), and one strain was toxigenic and classified as ribotype 064. One isolate was resistant to rifampicin, but both strains were susceptible to all other antimicrobials tested, including metronidazole and vancomycin. All C. difficile isolates and all staphylococcal strains resistant to antimicrobials were recovered from the same park. The present study suggests that free-living rodents in Belo Horizonte (Brazil) are mainly colonized by S. saprophyticus and may act as reservoirs of antimicrobial-resistant Staphylococcus spp. and C. difficile strains. This is the first study to evaluate the presence of staphylococci and C. difficile from free-living opossums and suggest a low fecal shedding of these organisms by these mammals.

English

Staphylococcus aureus is an important pathogen causing a wide variety of diseases such as skin infections, food poisoning, pneumonia and septicemia in humans and animals. Among the bacterial agents of food poisoning, S. aureus is the most common agent worldwide. The aim of this study was to assess prevalence of SEA, SEB enterotoxin producing S. aureus isolated from foodborne outbreaks in Iran. In this study, 313 diarrheal samples from 120 outbreaks were collected from December 2017 to August 2018. Isolates were identified using classical methods. The antimicrobial resistance patterns of the S. aureus isolates were assessed using standard disk-diffusion and E-test methods. Presence of sea and seb genes was investigated using polymerase chain reaction (PCR). Data were analyzed using SPSS and Excel Software as well as statistical tests. In this study, 55 samples (17.6%) from an overall number of 313 samples from food outbreaks were identified as S. aureus, which were assessed for their antimicrobial susceptibility. The highest contamination belonged to Yazd (50.9%) and Semnan (29.1%) Provinces. However, no contaminations of S. aureus were seen in Zanjan Province. The S. aureus was more common in females (50.9%) than males. Furthermore, S. aureus isolates were mostly resistant to penicillin (81.8%) and completely susceptibile to vancomycin. Of 55 isolates of S. aureus, four isolates (7.3%) were positive for sea and one (1.8%) for seb genes. The current study has shown that S. aureus food infection is one of the most common foodborne diseases, caused by the ingestion of staphylococcal enterotoxins produced by enterotoxigenic strains of staphylococci. Therefore, further screening and monitoring programs are suggested for the prevention of staphylococcal infections. &nbsp; Key words: Staphylococcus aureus, foodborne outbreaks, antibiotic resistance, sea, seb.