Standard Microbiological Tests Research Articles

The battle against dental caries: defeating biofilm formed by bacterial isolates using vanillin and plant essential oils: in vitro and ex vivo approaches

BackgroundInfections caused by biofilm-forming bacteria have significantly linked to dental plaque and caries. The aim of this study is to assess efficacy of some natural compounds in inhibition and eradication of biofilm formed by bacterial isolates from dental infections.ResultsBacterial isolates were recovered from dental plaque/caries and identified using standard microbiological tests and 16S rDNA sequencing. The isolated bacterial strains include Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Klebsiella pneumoniae, and Escherichia coli. The antibiotic susceptibility was determined by disk diffusion method and revealed that the majority of isolates showed high antibiotic resistance, and 61% of isolates were found to be multidrug resistant. The biofilm formation capacity of isolates was investigated using microtiter plate assay. Among the 77 bacterial isolates, seventeen showed moderate biofilm formation capacity, twenty-two showed near-moderate, thirty-four had weak biofilm-forming capacity, and four were non-biofilm producers. The antibiofilm activity of tested compounds (rose and jasmine oils, propolis, vanillin, and vinegar) was evaluated against isolates with highest biofilm-forming capacity. The in vitro antibiofilm ability of tested substances were investigated alone or in combination with each other to evaluate their ability to prevent biofilm formation or destroy preformed single-/multispecies biofilms. Finally, antibiofilm ability of tested combination was evaluated ex vivo on natural teeth. Our results showed that vanillin in combination with rose or jasmine oils showed promising biofilm inhibition and biofilm eradication activities in both the in vitro and ex vivo models.ConclusionsDental plaque and caries can be successfully prevented using combination of vanillin with rose or jasmine oils, and these compounds can be incorporated in new anticaries dental formulations.

Microbiological Profile and Antimicrobial Susceptibility Pattern of Uropathogens Isolated From Pregnant Women Attending a Tertiary Care Hospital in Central India.

Urinary tract infections (UTIs) are more common in females than males, and during pregnancy, frequency is increased due to hormonal changes affecting the anatomy and physiology. If not treated on time, complications may develop in both the mother and fetus. This study aimed to analyze the microbiological (bacterial and yeast) profile of the isolated uropathogens and their antimicrobial susceptibility. Aseptically collected urine specimens were processed by the standard loop method. Identification of uropathogens was done by standard microbiological tests, and antimicrobial susceptibility was performed as per the Clinical and Laboratory Standards Institute (CLSI) guidelines. Out of 400 study participants, UTI was detected in 26.75% (107/400) of cases. Overall, Escherichia coli (42.99%, 46/107) was the most frequently isolated uropathogen followed by Candida species (20.56%, 22/107), whereas, among gram-positive bacteria, Enterococcus faecalis (7.47%, 8/107) was the commonest. Among Enterobacterales, extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase (AmpC) production was observed in 19.35% (12/62, eight E. coli and four Klebsiella) and 6.45% (4/62, all E. coli) isolates, respectively. However, all the gram-negative organisms showed 100% (n=70) sensitivity to carbapenems. Among staphylococci, 50% (2/4) of isolates were methicillin-resistant, and high-level aminoglycoside resistance (HLAR) was observed in 75% (6/8) of Enterococcus faecalis isolates, but all were sensitive to vancomycin, linezolid, and nitrofurantoin. Among Candida species, non-albicans Candida (NAC) species (59%, 13/22) outweigh the number of Candida albicans (41%, 9/22), with Candida tropicalis (22.72%, 5/22) being the commonest NAC. All the Candida species were susceptible to voriconazole, whereas fluconazole resistance was observed in 31.81% (7/22) of Candida isolates, with a higher percentage in NAC species (22.72%, 5/22) than in Candida albicans (9.09%, 2/22). UTIs in pregnancy are caused by a spectrum of both gram-negative bacilli and gram-positive cocci. Moreover, there is a rise of both Candida albicans and NAC species as uropathogens, with the emergence of fluconazole resistance. There is an increased prevalence of asymptomatic bacteriuria in pregnancy, which necessitates the screening of pregnant females for UTI using culture and antimicrobial susceptibility testing.

Clinical Application of Metagenomic Next-Generation Sequencing in Sepsis Patients with Early Antibiotic Treatment.

This study aimed to evaluate the clinical utility of metagenomic next-generation sequencing (mNGS) in sepsis patients who received early empirical antibiotic treatment. A retrospective analysis was conducted on clinical data from sepsis patients diagnosed in the Emergency Intensive Care Unit (EICU) between April 2019 and May 2023. All patients underwent standard conventional microbiological testing. Patients were categorized into either the mNGS group or the control group based on whether they underwent mNGS tests. Baseline variables were matched using propensity scores. Out of 461 sepsis patients screened, 130 were included after propensity matching, with 65 patients in each group. Despite prior antibiotic treatment, 57 cases (87.69%) in the mNGS group had positive mNGS results, exceeding the culture detection rate (52.31%). Besides, a higher proportion of patients in the mNGS group experienced antibiotic adjustments compared to the control group (72.31% vs 53.85%). Mortality rates were also compared based on the duration of antibiotic exposure before mNGS sampling. Patients exposed to antibiotics for less than 24hours had a lower mortality rate compared to those exposed for over 8 days (22.22% vs 42.86%). COX multivariate analysis identified mNGS testing, underlying diseases, lymphocyte percentage, infection site (respiratory and bloodstream) as independent risk factors for mortality in sepsis patients. With increased antibiotic exposure time, the positive rate of culture testing significantly decreased (44.44% vs 59.52% vs 35.71%, P = 0.031), whereas the positive rate of mNGS remained stable (77.78% vs 88.10% vs 92.86%, P = 0.557). mNGS demonstrated less susceptibility to antibiotic exposure. Early mNGS detection positively impacted the prognosis of sepsis patients.

Distribution of chaperone-usher fimbriae and curli fimbriae among uropathogenic Escherichia coli

BackgroundIn the present study, we aimed to determine the frequency of the csgA, fimH, mrkD, foc, papaGI, papGII and papGIII genes, to provide and to design fimbrial adhesin gene (FAG) patterns and profiles for the isolated uropathogenic Escherichia coli (UPEC) strains.MethodsThe enrollment of 108 positive urine samples was performed during seven months, between January 2022 and July 2022. The UPEC strains were confirmed through the standard microbiological and biochemical tests. The antimicrobial susceptibility test was performed through the Kirby–Bauer disc diffusion method. Molecular screening of FAGs was done through the polymerase chain reaction technology. The statistical analyses including chi square and Fisher’s exact tests were performed to interpret the obtained results in the present study.ResultsAs the main results, the antimicrobial resistance (AMR) patterns,multi- (MDR) and extensively drug-resistance (XDR) patterns and FAG patterns were designed and provided. fimH (93.3%), csgA (90.4%) and papG (37.5%) (papGII (30.8%)) genes were recognized as the top three FAGs, respectively. Moreover, the frequency of csgA-fimH gene profile was identified as the top FAG pattern (46.2%) among the others. The isolates bearing csgA-fimH gene profile were armed with a versatile of phenotypic AMR patterns. In the current study, 27.8%, 69.4% and 1.9% of the UPEC isolates were detected as extended-spectrum ß-lactamases (ESBLs) producers, MDR and XDR strains, respectively.ConclusionsIn conclusion, detection, providing and designing of patterns and profiles in association with FAGs, AMR feature in UPEC strains give us an effective option to have a successful and influential prevention for both of UTIs initiation and AMR feature.

Identification and antimicrobial susceptibility profiles of Staphylococcus species isolated from raw cow milk, and swabs in smallholder dairy farms in Meta district, Eastern Ethiopia

BackgroundThe safety of milk production in terms of foodborne infections is a worldwide issue, particularly in developing countries where production is often unhygienic. A cross-sectional study was conducted from December 2018 to August 2019 in the Meta District of Eastern Hararghe Zone, Oromia Regional State, Ethiopia. We aim to assess milk hygiene practices among smallholder dairy farmers, estimate the prevalence of Staphylococcus aureus in raw cow milk and swabs, assess associated risk factors, and the antimicrobial susceptibility test of S. aureus isolates. Face-to-face interviews with 30 respondents randomly selected from smallholder dairy farmers were used to assess the potential risk factors for S. aureus contaminations in milk. A total of 177 samples were examined using standard microbiological testing. The disc diffusion technique was also employed to assess the antibiotic susceptibility of the isolates. The data was analyzed using STATA® version 14.0 statistical software.ResultsAccording to the milk hygiene assessment, 80% of respondents did not wash cow udder before milking, did not use detergent to clean milk containers, and did not keep milk refrigerated before consumption or sale, while 63.3% of milk consumers ingested raw milk. They had never heard of staphylococci foodborne disease. Likewise, the overall prevalence of S. aureus was 12.42% (95%CI: 8.32–18.98). The prevalence of S. aureus in udder milk, equipment swabs, and milkers’ hands was 18.8%, 26.7%, and 30%, respectively. The prevalence of S. aureus in milk is significantly associated with age, and mastitis history (p < 0.05). Moreover, old and mastitis positive animals were eight (OR: 8.40; 95%CI: 1.68–41.89) and four (OR: 4.33; 95%CI: 1.37–13.66) times more likely to be infected by S. aureus than adult, and mastitis negative animal. The isolates were resistant to penicillin G (97.4%) and tetracycline (69.2%) whereas susceptible to kanamycin, streptomycin, vancomycin, and cefotaxime, at 84.6%, 71.8%, 64%, and 58.8%, respectively.ConclusionThis study revealed the presence of antimicrobial-resistant patterns of S. aureus on commonly used antibiotics, as well as inadequate milk handling practices in the study area. Thus, awareness should be created on proper milk handling and hygiene as well as appropriate uses of antibiotics should be encouraged.

MassARRAY: a high-throughput solution for rapid detection of foodborne pathogens in real-world settings.

Bacterial foodborne pathogens pose a substantial global public health concern, prompting government agencies and public health organizations to establish food safety guidelines and regulations aimed at mitigating the risk of foodborne illness. The advent of DNA-based amplification coupled with mass spectrometry, known as MassARRAY analysis, has proven to be a highly precise, sensitive, high-throughput, and cost-effective method for bacterial detection. This study aimed to develop, validate, and evaluate a MassARRAY-based assay for the detection and identification of significant enteropathogenic bacteria. The MassARRAY-based assay was developed for the detection of 10 crucial bacterial foodborne pathogens, including Campylobacter coli, Campylobacter jejuni, Clostridium perfringens, Escherichia coli, Enterococcus faecalis, Enterococcus faecium, Listeria monocytogenes, Salmonella spp., Shigella spp., and Staphylococcus aureus. The assay was optimized using the reference gDNA (n = 19), followed by validation using gDNA (n = 85) of reference and laboratory isolates. Additionally, the evaluation of the assay's reaction using a mixture of gDNA from all nine targeted species was performed. The limit of detection of the developed MassARRAY-based assay was determined using bacterial cells. Moreover, the validation method for field samples was evaluated by comparing it with standard microbiological testing methods routinely analyzed. The developed MassARRAY-based assay demonstrated 100% concordance with known bacterial pure cultures. The assay's reaction using a mixture of gDNA from all nine targeted species revealed the MassARRAY's capability to detect all targeted species in a single assay with the lowest concentration of 1 ng/μL of gDNA. The limits of detection of the assay range from 357 ± 101 to 282,000 ± 79,196 cells. Moreover, the validation of the assay in field samples revealed a 100% correlation between the data obtained from the standard microbiological method and the MassARRAY-based assay. These findings suggested that the developed MassARRAY-based assay exhibited the excellence in high-throughput detection of foodborne bacterial pathogens with high accuracy, reliability, and potential applicability within real-world field samples.

Molecular Assessment of Resistance and Virulence Potential of Vibrio Species Isolated From Dumpsites in Port Harcourt, Nigeria

Background: Dumpsites have the potential to serve as reservoirs for various medically important bacteria and their virulence and resistance gene markers. For Vibrio spp., numerous genes associated with virulence have been identified in environmental strains. Due to the specific growth requirements of Vibrio spp., such strains can often be overlooked. This study aimed to assess the potential of Vibrio spp. isolated from two dumpsites in Port Harcourt, Nigeria, to serve as reservoirs of virulence and resistance genes. Methods: The soil samples were evaluated for the presence of Vibrio spp. following enrichment, using standard microbiological and biochemical test methods. DNA from Vibrio spp. was extracted using the boiling method, and isolates were tested for the presence of four resistance (sxt, strB, BlaTEM, and dfrA1) and four virulence (ctxA, hlyA, tcpA, and toxR) genes. Results: The study found a 40% occurrence of resistance genes and a 10% occurrence of virulence genes, with the strB streptomycin resistance gene being the most commonly detected (42%). Two of the virulence genes (ctxA and tcpA) were not detected. Seven of the test isolates exhibited multiple gene markers, with four gene markers present in each of two isolates. Conclusion: Overall, the study revealed a generally low potential for Vibrio sp. isolated from the dumpsites in Port Harcourt, Nigeria, to act as reservoirs of virulence and resistance genes. Additionally, the study reported an absence of major virulence markers associated with V. cholerae. A concerning finding was the high occurrence (42%) of the strB gene among these environmental isolates.

Correlation of CD4+ count and viral load with urinary tract infection and antimicrobial resistance pattern of bacterial uropathogens among HIV patients in Wolaita Sodo, South Ethiopia.

The permanence of HIV patients in healthcare provision centers exposes their weak immunity to various nosocomial microorganisms that migrate into and out of the hospital environment. The incidence of bacterial infections, including urinary tract infection, was inversely correlated with CD4+ T cells. Urinary tract infection (UTI) is one of the clinical problems among HIV patients. There was scarcity of published data on the relationship between viral load, CD4+ level, and UTI. This study aimed to assess the relationship between viral load and CD4 with bacterial UTI among HIV patients. The cross-sectional study was conducted in the Wolaita Sodo Town Health Center ART clinic. The socio-demographic data were collected using a pre-designed questionnaire. Patients' charts were reviewed to collect the current CD4 and viral load. Urine specimens were inoculated on blood agar, cysteine lactose electrolyte deficient (CLED) agar, and MacConkey agar, and bacterial species were finally identified using various biochemical methods. Antimicrobial sensitivity testing was conducted using standard microbiological tests. Bivariate and multivariate analyses were employed to describe the association between pairs of variables and to examine the relationship between independent variables and dependent variables. In this study, the overall prevalence of urinary tract infection (UTI) was 13.7%. Escherichia coli, Staphylococcus aureus, Pseudomonas aeroginosa, Staphylococcus saprophyticus, Proteus mirabilis, and Klebsiella pneumoniae were bacterial uropathogens detected in this study. E.coli (45.7%) was the predominant isolate followed by S. aureus (14.3%). Positive correlation between CD4+ count and urinary tract infection was detected and found statistically significant (r = 0.288 p > 0.01), whereas the viral load and urinary tract infection negatively correlated and showed statistically significant association (p < 0.01). The resistance rate of E.coli was 94%, 75%, and 69% to ciprofloxacin, norfloxacin, and cefepime, respectively. This study revealed that E.coli exhibited 94% and 75% resistance to amoxicillin-clavulanic acid and tetracycline, respectively. K. pneumoniae demonstrated complete resistance (100%) to amoxicillin-clavulanic acid, tetracycline, and trimethoprim-sulfamethoxazole, while showing 100% susceptibility to ciprofloxacin and nitrofurantoin. In the present study, the magnitude of the multi-drug resistance (MDR) was found to be 80%. CD4+ count, combination of antiretroviral therapy (ART) drugs, and a history of hospitalization were risk factors for urinary tract infection. In the current study, urinary tract infection emerged as a significant health concern among people living with HIV following their ART. The occurrence of urinary tract infection among HIV patients could be influenced by multifactorial factors that require further study. The CD4+ count was positively correlated with the prevalence of UTI, whereas the viral load was negatively correlated. The CD4+ count, combination of ART, and history of hospitalization were independent risk factors for UTI. The prevalence of MDR bacterial pathogens were notably high. Therefore, the treatment of UTI in HIV patients should be prescribed based on antibacterial susceptibility testing results.

Molecular characterization of carbapenemase and extended spectrum beta-lactamase producing Acinetobacter baumannii isolates causing surgical site infections in Ethiopia

BackgroundAcinetobacter baumannii is an opportunistic pathogen that can cause a variety of nosocomial infections in humans. This study aimed to molecularly characterize extended-spectrum beta-lactamase (ESBL) producing and carbapenem-resistant Acinetobacter species isolated from surgical site infections (SSI).MethodsA multicentre cross-sectional study was performed among SSI patients at four hospitals located in Northern, Southern, Southwest, and Central parts of Ethiopia. The isolates were identified by microbiological methods and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antibiotic susceptibility was determined using disk diffusion. The presence of phenotypic ESBL and carbapenemase production was detected by employing standard microbiological tests, including combined disk diffusion (CDT). ESBL and carbapenem resistance determinants genes were studied by polymerase chain reaction (PCR) and sequencing.ResultsA total of 8.7% Acinetobacter species were identified from 493 culture-positive isolates out of 752 SSI wounds. The species identified by MALDI-TOF MS were 88.4% A. baumannii, 4.7% Acinetobacter pittii, 4.7% Acinetobacter soli, and 2.3% Acinetobacter lactucae. Of all isolates 93% were positive for ESBL enzymes according to the CDT. Using whole genome sequencing 62.8% of the A. baumannii harbored one or more beta-lactamase genes, and 46.5% harbored one or more carbapenemase producing genes. The distribution of beta-lactamases among Acinetobacter species by hospitals was 53.8%, 64.3%, 75%, and 75% at JUSH, TASH, DTCSH, and HUCSH respectively. Among ESBL genes, blaCTX−M alleles were detected in 21.4% of isolates; of these 83.3% were blaCTX−M−15. The predominant carbapenemase gene of blaOXA type was detected in 24 carbapenem-resistant A. baumannii followed by blaNDM alleles carried in 12 A. baumannii with blaNDM−1 as the most common.ConclusionsThe frequency of Acinetobacter species that produce metallobetalactamases (MBLs) and ESBLs that were found in this study is extremely scary and calls for strict infection prevention and control procedures in health facilities helps to set effective antibiotics stewardship.

Molecular investigation of exoU and exoY virulence genes in Pseudomonas aeruginosa collected from hospitalized patients in North of Iran: A descriptive-analytical study

Objective: To investigate the frequency of exoU and exoY genes in patients with Pseudomonas aeruginosa infection. Methods: In this study, 100 clinical isolates of Pseudomonas aeruginosa were collected from patients hospitalized in educational- therapeutic hospitals and were identified using standard microbiological tests. Then, the antibiotic resistance pattern of the isolates was determined by the disk agar diffusion method. The bacterial DNAs were extracted by the alkaline lysis method. Finally, the presence of exoU and exoY genes was evaluated by the PCR test. Results: In this study, 47%, 72%, 29%, 39%, 40%, and 44% of the isolates were non-susceptible to piperacillin, aztreonam, ceftazidime, imipenem, tobramycin, and ciprofloxacin, respectively. In addition, 95% and 93% of the clinical isolates carried the exoU and exoY genes. Blood and fecal isolates had both virulence genes, while only one wound isolate had neither genes. Meanwhile, all urinary isolates contained the exoY gene and only one isolate lacked the exoU gene. Also, 88 isolates simultaneously had both exoU and exoY genes. Conclusions: High prevalence of exoU and exoY genes in this region indicates a significant role of type III secretion system in pathogenesis of Pseudomonas aeruginosa. The type III secretion system may be a suitable target to reduce the pathogenicity of this bacterium.

Investigation of Pseudomonas aeruginosa bacteria in a number of Baghdad schools and extent of their resistance to disinfectants and sterilizers

PurposeThis study was design to investigate of P. aeruginosa, an example of Gram-negative bacteria, in seven primary and secondary schools of Baghdad city, and the effects of Ethanol and Dettol of P. aeruginosa biofilm.Design/methodology/approachSeventy swabs were collected from seven primary and secondary schools of Baghdad city, Iraq, during November -December 2022. Swabs were collected from classes desk, doors handles, students hands and water taps. Standard microbiological testing methods were used on the samples for isolation and identification. The ability of bacteria to form biofilm and the effects of Ethanol and Dettol on"preformed” biofilms was examined by microtiter plate with the use of an ELISA reader.FindingsIn 70 swabs from seven primary and secondary schools, growth was observed in 33 swabs as P. aeruginosa. Primary schools were higher contaminated than secondary and water taps and door handles represented the main source of this contamination. The ability of bacteria to produce biofilm was observed in 19 (57.6%) isolates and 14 (42.4%) nonbiofilm producers. As well as, Ethanol (70%) treatment of preformed biofilms led to enhance biofilm formation and revealed significantly greater staining after 4 and 24h than Dettol (3%) compared to an untreated control (tryptic soy broth (TSB) incubation).Originality/valueStudies on P. aeruginosa in Iraqi schools are quite rare. This work is considered distinctive because it drew attention to the presence of pathogenic bacteria within primary and secondary schools, which are not considered their natural environment.

Capsular gene distribution and RAPD typing of Streptococcus agalactiae isolated from pregnant women

Streptococcus agalactiae has different virulence factors, from which the capsule has the most significant role in the pathogenesis of this organism. We aimed to investigate the distribution of more prevalent capsular genes among different Random Amplified Polymorphic DNA (RAPD) types of S. agalactiae isolated from pregnant women. A total of 106 isolates were collected from 420 vaginal and rectal swabs obtained from pregnant women. The specimens were transferred using Todd Hewitt Broth and were cultured on a blood agar containing antibiotics. The S. agalactiae isolates were identified by the standard microbiological and biochemical tests. The genomic DNAs of S. agalactiae isolates were extracted using an extraction kit. Then, the PCR method was used to detection of the capsular genes. Moreover, The RAPD PCR was used to genotyping of the isolates. The colonization rate of the pregnant women was 25.23%, and there was a statistically significant correlation between the weeks of gestation and the probability of colonization (p-value < 0.05). Also, 31 (29.24%) and 18 (16.98%) pregnant women had a history of abortion and membrane rupture, respectively. In addition, 20 (18.86%), 32 (30.18%), 4 (3.77%), and 6 (5.66%) isolates carried genes encoding capsular types Ia, Ib, III, and V, respectively. None isolates had the type II capsular gene, and other 44 isolates were non-typeable. Nine clones (clusters) of S. agalactiae were observed in the present study with 70% similarity, and 53 different types were identified among the isolates. Except for capsular types III and V that belonged to clones 3, 5, 7, and 9, other capsular types were detected in different RAPD types. We found that the capsular types Ib and Ia were predominant among pregnant women in this area, indicating their significance for vaccine designation. Also, our isolates showed a lower genotypic diversity in RAPD typing. This may be due to the same sources of most isolates.

Prospective cohort study of surgical site infections following single dose antibiotic prophylaxis in caesarean section at a tertiary care teaching hospital in Medchal, India.

Caesarean section (CS) is considered to be a life-saving operative intervention for women and new-borns in certain antepartum and intrapartum conditions. Caesarean delivery may be accompanied by several complications including surgical site infections (SSI). However, there is a significant lack of uniformity in the administration of antibiotics for preventing surgical site infections (SSI) following caesarean deliveries. The present study was conducted to determine the incidence of post CS SSI following the adoption of single-dose antibiotic prophylaxis as recommended by WHO at a tertiary care teaching hospital in Medchal, India. Also, to identify the risk factors of SSI and reported the bacteriological profiles and the antimicrobial susceptibility pattern of the culture positive isolates. To estimate the incidence of surgical site infections (SSI's) according to CDC criteria following WHO-recommended single-dose antibiotic prophylaxis for caesarean section at a tertiary care teaching hospital in Medchal, India. A prospective hospital-based study was conducted between June 2017 and December 2019, in which women who underwent caesarean delivery were followed up for 30 days post-delivery. Clinical details were collected using a structured questionnaire, and participants were followed up weekly after discharge to document any signs and symptoms of SSI. Symptomatic patients were requested to come to the hospital for further investigation and treatment. Standard microbiological tests were conducted to detect microorganisms and their antibiotic sensitivity. The study included 2,015 participants with a mean age of 24.1 years. The majority were multigravida (n = 1,274, 63.2%) and underwent emergency caesarean delivery (n = 1,232, 61.1%). Ninety two participants (4.6%, 95% CI: 3.7% to 5.6%) developed surgical site infections, with 91 (98.9%) having superficial and 1 (1.1%) having a deep infection. Among those who developed an SSI, 84 (91.3%) did so during their hospital stay, while 8 (8.7%) developed an SSI at home. The adjusted relative risk (a RR) for developing an SSI was 2.5 (95% CI: 1.4 to 4.6; power 99.9%) among obese women and 2.3 (95% CI: 1.1 to 4.7; power 100%) among women aged 25 years or younger. Microbial growth in culture was observed from 55 (75.8%) out of total 66 samples. The most common organisms identified were Staphylococcus aureus (n = 7(12.3%)23, 46.0%), Klebsiella sp. (n = 13, 26.0%), and Escherichia coli (n = 12, 24.0%). The rate of SSI following caesarean deliveries subjected to single dose antibiotic prophylaxis was low. Young women and obese women were at high risk of developing SSI.

Physician-directed microbiological testing versus syndromic multiplex PCR in gastroenteritis.

Syndromic multiplex PCR testing is an alternative to conventional stool testing based on physician-directed request forms. The objective of this study was to compare the etiologic yield of conventional microbiological testing based on physician-directed request forms with that of rapid syndromic testing. In addition, the adequacy of the clinician ordering, which is an important piece of the diagnostic stewardship, was evaluated. Physician-directed conventional microbiological testing and extensive molecular syndromic testing with the Fast Track Diagnostics Gastroenteritis Kit were performed in parallel on 1238 samples to evaluate the contribution of a multiplex panel to the diagnostic process of gastroenteritis. A potential causative pathogen was identified in 18.4% of stool samples by standard microbiological testing and in 41.3% of stool samples tested using the syndromic panel. Only 15.1% of the request forms could be considered successful of which 88.2% were labeled inadequate. Conventional physician-directed based testing missed the etiologic diagnosis in 32.3% of the specimens (excluding sapovirus and astrovirus). Bacterial infections were theoretically not missed as bacterial stool culture was requested on all stool samples, but in 28.6% of the cases, no isolate could be recovered. In 36.9% of the samples testing positive for a viral pathogen, no viral testing was requested. In addition, 72.5% of all samples positive for a parasite were clinically suspected by the physician. This study suggests that syndromic multiplex PCR assays are a better strategy for pathogen detection in patients with gastroenteritis than physician-directed laboratory testing based on the clinical presentation.

Phenotypic and Genetic Characterization of Polyhydroxyalkanoate Producing Bacterial Isolates from Hypersaline Water Body, Atlantic Ocean, Nigeria

Introduction: The importance of polyhydroxylalkanoate (PHA) producing bacteria is hinged on the basis that PHA itself possess environmentally advantages over synthetic plastics therefore, the proper identity of these bacteria is inevitable.&#x0D; Aim: To determine the bacteria identification methods of phenotypic and genetic identification for marine sourced effective polyhydroxylalkanoate (PHA) production.&#x0D; Study Design: Randomised design was employed for PHA producing bacterial isolates.&#x0D; Place and Duration of Study: Samples containing PHA-producing bacteria from the hypersaline water body of Nigerian Southern Atlantic Ocean (6.35ᴼ N 3.28ᴼ E -St1; 6.35ᴼ N 3.40ᴼ E -St2; and 6.36ᴼ N 3.47ᴼ E -St3); water depths (0.07m (top), 50m (middle) and 100m (bottom) were collected and investigated between August, 2016-September, 2019.&#x0D; Methodology: Bacterial isolates was characterized using standard microbiological and biochemical tests for the phenotypes, and 16S rDNA for the genotypes. Isolates were also screened for PHA potentials using specific primers.&#x0D; Results: Genetically identified Bacillus cereus strains LB17 and Bacillus paramycoides SA27 were phenotypically identified as Bacillus badius. Similarly, Acinetobacter calcoaceticus JL11, five strains of Alcaligenes faecalis, seven strains of Bacillus spp., Enterobacter cloacae, Falsochrobactrum ovis, Ochrobactrum ciceri, Providencia stuartii including two species of Pseudomonas and Bordetella trematum were all phenotypically identified as Corynebacterium kutsceri. Invariably, Alcaligenes faecalis (strains PSD10 and DEP8), Pseudomonas aeruginosa (H47921) and Vagococcus fluvialis (AWW1) were identified as Staphylococcus species. All 34 bacterial isolates expressed phaC genes for PHA potential, while Alcaligenes faecalis strains and Bacillus humi (NBPP9) expressed phaC1 for short PHA chain.&#x0D; Conclusion: This study established variations in the genetical identity of Corynebacterium kutsceri, Enterobacter amnigenus, Micrococcus luteus, Micrococcus varians, Staphylococcus epidermidis and Staphylococcus saprophyticus when compared with the phenotypic identification methods. But, there was synchronization in the genotypic and phenotypic identity of bacillus species. Records of varietal differences of PHA potential were also obtained from same species in this research. It is therefore pertinent to rely on the genetic identification of bacteria for the effective determination of PHA-producing character as displayed in Bacillus spp.

Extended-Spectrum Beta-Lactamases Genes in Klebsiella pneumoniae Isolates Obtained from Patients in Intensive Care Units

Background: Drug-resistant hospital-acquired infections (HAIs) are a growing concern in modern medicine throughout the world. Klebsiella pneumoniae is one of the most prominent causative agents of multidrug-resistant nosocomial infections. It is also widely recognized for having a high resistance level to many antibiotic classes, particularly beta-lactams. Carbapenemase-producing K. pneumoniae has been identified as a major global cause of HAIs with adverse clinical outcomes. Therefore, it is of the utmost importance to have an in-depth understanding of the antimicrobial resistance (AMR) genetic determinants of this bacterium to stop the spread of highly resistant K. pneumoniae in healthcare facilities and the resulting patient morbidity and mortality. Objectives: This study aimed to investigate the AMR pattern of K. pneumoniae isolates obtained from intensive care units (ICUs), with a focus on extended-spectrum beta-lactamases (ESBLs) genes blaCTX-M, blaGES, and blaIMP. Methods: A total of 105 K. pneumoniae isolates obtained from the sputum samples of ICU patients were identified and confirmed using standard microbiological tests and 16S rRNA polymerase chain reaction (PCR). The antibiotic susceptibility test was performed for all the isolates. The presence of ESBL genes was determined phenotypically and by PCR. Results: The highest level of resistance was observed against ceftazidime (100%), cefotaxime (99%), and imipenem (93.3%). Approximately 87.6% and 39% of the isolates were sensitive to colistin and gentamicin, respectively. Phenotypic ESBL production was observed in 16 isolates, and the prevalence of blaCTX-M was 86.7%. No blaGES and blaIMP genes were detected. Conclusions: Periodic investigation of AMR-mediating genes is essential due to the high prevalence of ESBL genes in HAIs. The presence of other ESBL genes needs to be investigated for a more accurate understanding of the AMR status of K. pneumoniae in healthcare settings.

Isolation and characterization of bacteria from babies heat prickly powder purchased in Umuahia, Abia state

Aim: To isolate and Characterize Bacteria from Babies Heat Prickly powders purchased in Umuahia, Abia state Method: A total of Ten (10) Baby heat prickly powder samples were randomly purchased from different market locations in Umuahia, Abia state. Isolation and identification of Bacteria were conducted using standard microbiological techniques. Bacteria were Characterized using standard microbiological and biochemical test. Results: The isolated Bacteria include Staphylococcus aureus, Bacillus sp, Staphylococcus epidermidis and Pseudomonas aeruginosa. Staphylococcus aureus had the highest percentage occurrence (40%) while other Bacteria had (20%) each with the total bacteria count (TBC) ranging from 4.3 ×104 CFU/g to 1.32 ×105 CFU/g. Conclusion: High bacterial load was observed in the present study which showed there was contamination of most of the products in respect to the international Microbiological standards recommended limits for bacterial contamination in powder/Cosmetic products (1.0 x 103 CFU/g) for bacteria. This could be as a result of poor manufacturing practices, poor hygiene, contaminated raw materials or the susceptibility of the ingredients contained in the baby powders.

Prevalence study of methicillin resistant &lt;i&gt;Staphylococcus aureus&lt;/i&gt; and its SCC&lt;i&gt;mec&lt;/i&gt; features in horses and handlers in Zaria and Kaduna, Nigeria

Methicillin resistant Staphylococcus aureus (MRSA) is a pathogen with public health implications being resistant to most used antibiotics. It has been associated with health facilities but has now become prevalent in community settings. The presence of MRSA in 240 apparently healthy horses and 65 horse handlers in Kaduna and Zaria was studied through nasal swabs collection by a one-stage cluster sampling and analysed using standard microbiological tests and genotyping methods. Questionnaires were also administered to assess for risk factors associated with MRSA carriage. Prevalence was 10% and 6.2% from the horses and horse handlers respectively. The S. aureus isolates showed highest resistance rates of 54.6% to penicillin and oxacillin. There were high resistance rates also to erythromycin, and tetracycline of 47.7% and 34.1% respectively. Resistance of 22.7% to amikacin and gentamicin, 6.8% to sulphamethoxazole+trimethoprim, 2.3% to ciprofloxacin, and 2.3% to chloramphenicol were also observed. Multidrug resistance (MDR) was found among 74.8% of the MRSA isolates. SCCmec typing showed types I, III, and IV in both the horses and the horse handlers while one horse was found to carry SCCmec V. Possible risk factors identified for MRSA carriage by horse handlers included being a veterinarian, exposure to antimicrobial agents, healthcare facility visitation, and personal hygiene. For the horses, risk factors from this study were allergy and wound management. MRSA nasal carriage in horses and horse handlers, as well as MDR (multidrug resistant) strains of S. aureus have been established from this study, this is of public health concern.

Biorisk Management and Antibiotic Susceptibility Pattern of Biofilm producing Pseudomonas aeruginosa Isolated from Broiler Chicken: A Public Health Concern

Control of biosecurity and biosecurity within poultry consists of a set of practical measures meant to prevent and control the spread of disease between people and animals. Infections, caused mainly by zoonotic agents, occur frequently due to the lack of safety monitoring regulations, as well as the inappropriate use of antimicrobial products, leading to the emergence of antimicrobial-resistant microorganisms. Pseudomonas aeruginosa, often known as the MDR pathogen has evolved resistance to multiple antibiotics. Because of its propensity to build biofilms in meat and other food products, P. aeruginosa is even more resilient to the phenomenon of drug resistance which is a major public health issue. Standard microbiological and biochemical tests were used to isolate and identify P. aeruginosa from a total of 100 meat samples (20 from each district from broiler chicken meat) gathered from various butcher shops and supermarkets. The Kirby Bauer method was used to identify antibiotic resistance, while the microtiter plate test was used to monitor biofilm formation. It was found that P. aeruginosa was identified from 22% of the broiler chicken meat samples and showed resistance to Cloxacillin, teicoplanin, ciprofloxacin, imipenem, and meropenem, followed by linezolid, streptomycin, amikacin, compound sulphonamide, aztreonam and cefepime which showed intermediate resistance. Multiple Antibiotic Resistance Index (MARI) was calculated as 0.45 for a total of 11 antibiotics. Also, all 22 MDR isolates of P. aeruginosa tested positive for the presence of the biofilm. In conclusion, it was determined that chicken meat was contaminated with Pseudomonas aeruginosa, and these strains that produce biofilms are more resistant to antibiotics. Thus, there is a serious threat to public health from biofilm-forming isolates found in broiler chickens.

Characterization of beta-lactamase producing Enterobacterales isolated from an urban community wastewater treatment plant in Iran.

he occurrence and characteristics of Extended Spectrum- and AmpC-β-lactamase producing Enterobacterales (ESBL-PE and AmpC-PE) in an urban wastewater treatment plant (WWTP) were investigated. A total of 30 wastewater samples were collected from all sections of WWTP. Enterobacterales were isolated and identified using standard microbiological tests. The antibiotic resistance profile was determined by the Kirby-Bauer disk diffusion method. Phenotypic screening for ESBL-PE and AmpC-PE isolates was performed by double-disk synergy and boronic acid disk potentiation tests, respectively. The isolates were examined for AmpC- and ESBL-encoding genes by PCR and sequencing methods. Among 146 Enterobacterales isolates, 8.9% (n=13) [ESBL-only; 5.48% (n=8) and ESBL + AmpC; 3.42% (n=5)] were ESBL-producers and 15.75% (n=23) [AmpC-only; 12.33% (n=18) and ESBL + AmpC; 3.42% (n=5)] AmpC-producers. Hafnia spp. with 33.33% (n=1/3) and E. coli with 20.58% (n=7/34) [ESBL-only; 17.64% (n=6/34) and ESBL + AmpC; 2.94% (n=1/34)] were the most common ESBL-producing bacteria. Enterobacter spp. with 37.50% (n=6/16) of isolates were the most common AmpC-producing organisms. ESBL- and/or AmpC-producing isolates were identified in all parts of the WWTP including 80% (n=8/10) of samples taken from effluent. Among ESBL-producing isolates, bla CTX-M , bla TEM, and bla SHV ESBL-encoding genes were found in 61.5% (n=8), 15.3% (n=2), and 7.7% (n=1) of isolates, respectively. All CTX-M-type enzymes belonged to the CTX-M-1 group and CTX-M-15 subgroup. bla TEM and bla SHV type genes belonged to bla TEM-20 and bla HSV-12 subtypes, respectively. bla DHA with 73.9% (n=17/23), and bla CIT and bla FOX with 30.4% (n=7/23) each, were the most common AmpC-encoding genes among AmpC-producing isolates. Overall, 75% of ESBL-producing and 55.5% of AmpC-producing isolates exhibited multi-drug resistance phenotypes. The organisms were most resistant against ampicillin (82.2%) nalidixic acid (43.8%) and cephalexin (41.1%). ESBL- and AmpC-producing Enterobacterales spp. with diverse genetic resistance backgrounds in WWTP effluent poses a significant risk to public health.