Canadian Journal of Infectious Diseases & Medical Microbiology最新文献

Health professionals in ophthalmic clinics prescribe broad-spectrum topical antibiotics empirically, a major contributing factor to antimicrobial resistance. This practice is also observed in our study area. Thus, this study was done to identify the bacterial spectrum, determine antimicrobial resistance, and identify factors of external eye infections. A cross-sectional study was done from May to December 2023 with a systematic random sampling technique. The study participants' data were collected using a semistructured questionnaire. The specimen was taken aseptically and processed using standard microbiological methods. A total of 413 subjects were enrolled in this study. The overall prevalence of bacterial isolates was 52.8% (218/413) [95% CI: 48.0-57.6]. Gram-positive bacteria [70.6% (154/218)] predominate over gram-negative bacteria [29.4% (64/218)]. Considerable bacteria have shown a high percentage of resistance to penicillin and ampicillin. History of eye surface disease (AOR: 11.79, 95% CI: 2.79-49.69; p = 0.001) and previous usage of antibiotics (AOR: 3.47, 95% CI: 1.12-10.73; p = 0.031) have shown a significant association with bacteria isolated from the external part of the eye. The prevalence of bacteria isolated from the external eye was relatively high. Most bacteria have shown resistance to penicillin and ampicillin. Hence, antimicrobial susceptibility tests better monitor the empirical treatment of external eye infections.

Background: Methicillin-resistant Staphylococcus aureus (MRSA), has the ability to cause biofilm associated chronic infections with a high mortality rate. This creates a demand for the improved antibiofilm therapies. The aim of this study was to evaluate the anti-MRSA and antibiofilm activity of a natural product, chlorogenic acid, in synergy with an antibiotic, cefazolin. Material and Methods: The synergistic effect was measured by the checkerboard method. The antibiofilm activity was analysed by crystal violet staining, MTT assay, and atomic force microscopy (AFM). The cytotoxic effect on Human Embryonic Kidney (HEK 293) cells was determined using the MTT assay. Assays were performed in triplicate, and compared using the one-way ANOVA test. Results: When chlorogenic acid and cefazolin were combined at low concentrations, a strong biofilm inhibition in terms of biofilm biomass (88%), and metabolic activity (82%) was observed, as compared to the results obtained for each compound alone. AFM images of biofilms, treated with chlorogenic acid combined with cefazolin, revealed a high destruction of biofilms and extracellular polymeric substances, as compared to each drug alone. A nontoxic effect on HEK 293 cells was observed for the combination of chlorogenic acid and cefazolin. Conclusion: Chlorogenic acid can be used as an adjuvant with currently used antibiotic in the development of combinatory therapies to treat biofilm-associated bacterial infections.

Background: The COVID-19 pandemic has disproportionately affected pregnant individuals, increasing risks of severe illness and adverse outcomes. While vaccination is a key mitigation strategy, initial exclusion from clinical trials led to limited safety data. Despite evidence of vaccine effectiveness, hesitancy persists in this population. Objective and Sources: This meta-analysis aims to evaluate the efficacy and impact of COVID-19 vaccination in pregnant individuals, synthesizing evidence from 82 studies (3,676,654 participants) retrieved from PubMed, Embase, Cochrane Library, and Scopus (2019-2024). Study quality was assessed using the Newcastle-Ottawa scale (80/82 scored ≥ 7). Key Findings: Vaccination reduced maternal SARS-CoV-2 infection risk by 48% (odds ratio [OR] = 0.52), with mRNA vaccines showing higher efficacy (52% vs. 43% for inactivated). Maternal hospitalization risk decreased by 42% (OR = 0.58), and severe outcomes by 50% (OR = 0.50). Furthermore, neonatal outcomes improved, including reduced infection (OR = 0.69), preterm birth (OR = 0.87), stillbirth (OR = 0.64), and neonatal death (OR = 0.47). Protection against neonatal death was stronger in individuals without prior infection (OR = 0.43). Third-trimester vaccination may offer better protection against preterm birth. Conclusion: Overall, COVID-19 vaccination during pregnancy effectively mitigates infection and adverse maternal/neonatal outcomes, supporting its clinical recommendation.

Aim: The purpose of this study was to investigate the impact of filler content and polishing of resin-based composites on in vitro biofilm formation of Candida and Streptococci species. Materials and Methods: Specimens of four commercially available resin-based composites including Z100, P60, Z250, and Z350, with different filler amounts and volumes, were prepared according to the manufacturer's instructions. Each group was divided into polished and unpolished specimens, which were then placed in a 24-well tissue culture plate with microbial suspension and incubated. The XTT technique was used to evaluate biofilm formation. Results: Z250 resin-based composites, which had the highest percentage of filler (68%), had the highest biofilm metabolic activity. A significantly less microbial biofilm metabolic activity was noted on P60 polished resin-based composites than on unpolished groups (p < 0.001). Polishing procedures reduce biofilm metabolic activity. Streptococcus salivarius produced the least biofilm metabolic activity among the Streptococcal species (p < 0.001). However, there were no statistically significant differences between Candida species in the biofilm metabolic activity. Conclusion: The results revealed that the amount of filler in resin-based composites had a major impact on the biofilm metabolic activity. Therefore, resin-based composites with a minimized excess resin matrix, minimized filler amount, and smoother surfaces might be more useful in reducing biofilm metabolic activity and secondary caries. These findings may be useful for modifying novel resin-based composite formulations to improve oral health and patient wellbeing.

Bloodstream infections (BSI) in ICU settings are associated with high morbidity, mortality, and healthcare costs. The ICU environment, with its high use of invasive devices and immunocompromised patients, fosters an increased risk for multidrug resistance (MDR) pathogens, complicating treatment strategies. Understanding the epidemiology and resistance patterns in these settings is essential for improving patient outcomes and guiding appropriate antimicrobial stewardship practices. This study retrospectively analyzed data from 640 blood culture samples collected in the ICU of the Affiliated Hospital of Jiaxing University between January 2021 and December 2023. The blood samples were appropriately collected and cultured. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was employed to identify the isolated strains. Antimicrobial sensitivity was assessed using the VITEK2 system, the Epsilometer test (E-test), and the Kirby-Bauer disk diffusion method. All statistical analyses were conducted using IBM SPSS Statistics 22.0. A total of 391 bacterial pathogens (61.1%) were isolated. The predominant pathogens causing BSI were Gram-negative bacteria. The most prevalent pathogens during the period were coagulase-negative Staphylococci (CoNS, 17.1%), followed by Klebsiella pneumoniae (K. pneumoniae, 13.6%), Enterococcus spp (13.6%), Escherichia coli (E. coli, 12.3%), Acinetobacter baumannii (A. baumannii, 8.4%), and Staphylococcus aureus (S. aureus, 5.1%). Among the antibiotics tested, tigecycline, linezolid, vancomycin, and quinupristin/dalfopristin were effective against Staphylococci and Enterococci, although some CoNS strains exhibited resistance to vancomycin. Tigecycline showed effectiveness against the main gram-negative bacteria. Furthermore, multiple hospitalizations, comorbidity with diabetes, and the use of a central venous catheter were identified as significant risk factors for multidrug-resistant organisms (MDROs) in BSI cases. Pathogens isolated from the bloodstream of ICU patients exhibited significant drug resistance. We recommend strategies to mitigate the incidence of MDROs in BSI, including limiting the duration of hospital stays, closely monitoring underlying patient conditions, improving discharge plans, and strengthening transitional care, and prevent infections associated with central venous catheters.

Neurolisteriosis is a listerial invasive disease, which is characterized by brain parenchymal and meningeal involvement, with a high fatality rate and frequent neurological sequelae. The main clinical presentations of neurolisteriosis are meningitis, meningoencephalitis, rhombencephalitis, and brain abscess. Neuroradiological imaging is useful to distinguish these clinical presentations. The diagnosis of neurolisteriosis may be confirmed by cerebrospinal fluid or blood cultures, but these tests may have different yields depending on the clinical presentation of neurolisteriosis. The elderly and immunocompromised patients are the most susceptible population to developing neurolisteriosis, and few cases occur in healthy young people. This disease is caused by Listeria monocytogenes, a foodborne pathogen with an intracellular life cycle, which can be found in processed foods, and it remains the third cause of bacterial meningitis in adults. Most cases of neurolisteriosis are community-acquired, but several hospital-acquired cases and outbreaks have been reported in the literature and linked to the consumption of food served to inpatients. Aminopenicillins are the antibiotics with the highest impact on the prognosis of neurolisteriosis, and alternative antimicrobial therapies must be considered in those cases where a first-choice antibiotic cannot be administered or with antibiotic treatment failure. In this article, the epidemiology, sources of infection, pathogenesis, and clinical aspects of neurolisteriosis are reviewed, highlighting the main clinical presentations of the disease. Relevant information regarding hospital-acquired neurolisteriosis is also included to provide a framework for discussing nosocomial cases definition.

[This corrects the article DOI: 10.1155/2022/4503964.].

Effective management of hospital-acquired infections caused by Staphylococcus aureus necessitates a comprehensive understanding of bacterial characteristics. The genotyping of clinical samples of methicillin-resistant S. aureus (MRSA) isolates plays a crucial role in understanding the pathogen's epidemiology, etiology, and antibiotic resistance patterns. This study investigated the genotyping and antibiotic resistance profiles of clinically isolated S. aureus strains from different hospitals in Isfahan, Iran. Sixty-three MRSA isolates were analyzed using the disc diffusion method. After DNA extraction, multilocus sequence typing (MLST) was performed using seven housekeeping genes, revealing genetic diversity. Six isolates were selected based on their resistance patterns for MLST. The most frequent isolates were detected from wounds (41.3%), and the lowest frequency was from synovial samples (1.6%). Based on the antibiotic resistance pattern, the highest antibiotic resistance of S. aureus isolates was related to tetracycline, ciprofloxacin, and clindamycin at 68.3%, 44.4%, and 44.4%, respectively. In contrast, 96.8% and 95.2% of the isolates were sensitive to nitrofurantoin and linezolid. Among resistant isolates, six sequence types (STs) were identified, including ST74, ST239, ST805, ST531, ST859, and ST5. This study highlights the prevalence, antibiotic resistance, and genetic diversity of MRSA isolates in Isfahan, Iran. The identification of clonal complexes (e.g., CC5, CC8, CC30) suggests clonal spread, emphasizing the importance of surveillance and prevention strategies.

Background: While testing healthcare workers (HCWs) for SARS-CoV-2 is important to reduce transmission within healthcare settings, understanding the self-reported patterns of testing is important for interpreting vaccine effectiveness and other COVID-19-related information. Objective: Using longitudinal data from the COVID-19 cohort study, this study described trends in SARS-CoV-2 testing among Canadian HCWs between June 2020 and November 2023. Methods: HCWs completed an illness report for each instance of SARS-CoV-2 testing and episodes of symptoms compatible with COVID-19 even if untested. Overall rates of testing among the participating cohort were calculated. Rates were stratified by province, reason for testing and COVID-19 vaccination status using 4-week intervals to smooth estimates. For episodes of symptomatic illness (only), the median time between symptom onset and first test was calculated, along with the percent of episodes initially receiving a negative result for SARS-CoV-2 that were reported as being retested. Results: Rates of testing for SARS-CoV-2 generally mirrored rates of hospitalisation for COVID-19 among Canadians. Rates of testing were highest during the Omicron BA.1 wave (11.9 participants tested at least once per 1000 person-days) and varied by province; vaccination status did not impact rates. The most common reason for testing was for symptoms. Testing for known exposure or routine reasons greatly decreased after the Omicron BA.1 wave. In participants who were tested for episodes of symptomatic illness, the median time between symptom onset and first test was 1 day (interquartile range 0-2). Reported retesting after an initial negative result remained low throughout the study period. Conclusions: Understanding testing behaviours is important for public health decision-making including the analysis and interpretation of case data and vaccine effectiveness studies. It can also highlight possible missed case-finding opportunities in healthcare settings.

Introduction: Readmission to the hospital after an acute COVID-19 infection varies in the literature in terms of rate, causes, and outcomes. The 30-day readmission rate ranges from 4% to as high as 11.3%. The causes of readmission after a COVID-19 admission are diverse and include persistent respiratory symptoms, hypoxia, secondary bacterial infection, and thromboembolic disease. This study aims to describe the causes of hospital readmission within 30 days of discharge following an acute COVID-19 infection. Methods: This retrospective cohort study was conducted at a tertiary care center in Riyadh, Saudi Arabia, between March 2020 and February 2022 and included all adult patients who were readmitted to the hospital within 30 days after a primary hospital admission due to COVID-19 infection. Results: A total of 3517 patients were hospitalized with acute COVID-19 infection during the study period, and 200 patients were rehospitalized within 30 days postdischarge, resulting in a readmission rate of 5.7%. The mean age of the readmitted patients was 66.35 ± 19.5 years, and 105 (52.5%) were male. Hypertension and diabetes mellitus were the most common comorbidities. Chronic respiratory disease was present in 44 patients (22%) prior to their acute COVID-19 infection. The mean time to readmission was 7.86 ± 5.8 days. Persistent COVID-19 pneumonia was the most common cause of readmission, diagnosed in 105 patients (52.5%), followed by renal impairment in 29 patients (14.5%). Urinary tract infections were the leading infectious cause of readmission, occurring in 23 patients (11.5%), while secondary bacterial pneumonia was rare. Shortness of breath and cough were the most common symptoms at the second presentation. Respiratory therapeutic interventions were required for 120 patients (60%), and 45 patients required intensive care unit (ICU) admission. Compared to the index admission, a higher proportion of patients required ICU admission and mechanical ventilation. After the index admission, most patients were still symptomatic at discharge (moderate to critical National Early Warning Scores (NEWS)). Conclusion: The readmission rate after acute COVID-19 infection was 5.7%, aligning with rates reported internationally. The most frequent causes of readmission were persistent COVID-19 pneumonia, renal impairment, and urinary tract infections, while secondary bacterial pneumonia at readmission was rare. Readmission was associated with increased rates of ICU admission and the need for mechanical ventilation. The use of NEWS at discharge may serve as a useful criterion for determining readiness for discharge. Future follow-up of this cohort of patients will determine chronic long-term respiratory complications.