Biofilms are accumulations of microorganisms in an extracellular polymeric substance matrix which are composed of polysaccharides, proteins, lipids, and nucleic acids. Many bacteria can switch between a planktonic form and a biofilm form. The planktonic bacteria have relatively high cell growth and reproduction rates and have a reduced likelihood of survival but can adapt to occupy new habitats. The biofilm state appears to be a natural and predominant state of bacteria. The need for the formation of bacterial biofilm is that it enhances the tolerance of bacteria to harsh environmental conditions, thereby allowing bacteria to avoid being washed away by water flow or the bloodstream by simply attaching to a surface or tissue, and the EPS matrix protects bacteria cells, in deeper layers, against antimicrobial agents, probably by limiting the diffusion of these agents. Biofilm formation steps are initial contact/attachment to the surface, followed by micro-colony formation, maturation and formation of the architecture of the biofilm, and finally detachment/dispersion of the biofilm. Once formed, biofilm restricts bacterial mobility and increases cell density. Secretions of autoinducers into the environment are critical for cross-signaling between bacteria. This cross-talk is called quorum sensing (QS). Quorum sensing is a cell–cell communication mechanism between bacteria that allows specific processes to be controlled, such as biofilm formation and virulence factor expression. Bacterial quorum sensing signaling mainly consists of acyl-homoserine lactones (produced by Gram-negatives), autoinducing peptides (produced by Gram-positives), and autoinducer-2 (produced by both Gram-negatives and Gram-positives). Therefore, this review is aimed at how bacterial biofilms work and are formed.

Background: Antimicrobial-resistant (AMR) bacterial infection is a significant global threat to the healthcare systems. Pseudomonas aeruginosa, the leading infectious agent in the healthcare setting is now one of the major threats due to AMR. A comprehensive understanding of the magnitude of AMR, particularly highly public health important pathogens such as P. aeruginosa, is necessary for the management of infections based on local information. Objective: This systematic review and meta-analysis aimed to determine the country-wide AMR of P. aeruginosa. Methods: Systematic searches were performed to retrieve articles from PubMed, Scopus, Web of Science, ScienceDirect electronic databases, Google Scholar search engine, and repository registrars from 2015 to 31^st December 2023. Twenty-three studies that provided important data on AMR in P. aeruginosa were systematically reviewed and analyzed to determine the country-wide magnitude of P. aeruginosa AMR profile from healthcare-associated infections. AMR of P. aeruginosa to 10 different antibiotics were extracted separately into Microsoft Excel and analyzed using STATA 17.0. Cohen’s kappa was computed to determine the agreement between reviewers, the Inverse of variance (I²) was used to evaluate heterogeneity across studies, and Egger’s test to identify publication bias. A random effect model was used to determine the pooled resistance to each antibiotic. Subgroup analysis was performed by infection type and year of publication. Results: This systematic review and meta-analysis revealed that the pooled prevalence of P. aeruginosa in clinical specimens associated with HAI was 4.38%(95%CI: 3.00–5.76). The pooled prevalence of AMR in P. aeruginosa for different antibiotics varies, ranging from 20.9% (95%CI: 6.2–35.8) for amikacin to 98.72% (95%CI: 96.39–101.4) for ceftriaxone. The pooled resistance was higher for ceftriaxone (98.72%), Trimethoprim-sulfamethoxazole (75.41), and amoxicillin-clavulanic acid (91.2). In contrast relatively lower AMR were observed for amikacin (20.9%) and meropenem (28.64%). The pooled multi-drug resistance (MDR) in P. aeruginosa was 80.5% (95%CI: 66.25–93.84). Upon subgroup analysis by infection types and year of publication, P. aeruginosa isolated from healthcare-associated infections exhibited higher resistance to ceftazidime (94.72%) compared to isolates from mixed types of healthcare-associated infections (70.84%) and surgical site infections (57.84%). Antimicrobial resistance in gentamicin was higher during the periods of 2018–2020 (73.96%), while comparatively lower during 2021–2023 (42.69%) and 2015–2017 (29.82%) Conclusions: Significantly high AMR and MDR were observed from this systematic review and meta-analysis. AMR obtained from this systematic review and meta-analysis urges the need for improved infection control, antimicrobial stewardship practices, and strengthened surveillance systems to control the spread of AMR and ensure effective treatment of P. aeruginosa infections. Protocol registration: This systematic review and meta-analysis was registered on PROSPERO (Registration ID: CRD42024518145).

Enterococcus faecalis (E. faecalis) is a major cause of healthcare-associated infections (HAIs). It exhibits a strong biofilm-forming ability, which contributes to treatment resistance and persistence. Despite its clinical relevance, the global prevalence of biofilm-forming E. faecalis remains poorly defined. This study aimed to estimate the pooled prevalence of biofilm-forming E. faecalis in clinical isolates worldwide. Following PRISMA 2020 guidelines, we systematically searched PubMed, Scopus, ScienceDirect, Google Scholar, and institutional repositories for studies published between 2015 and 2024. A total of 56 studies involving 3,739 clinical isolates met the inclusion criteria. We used a random-effects model to estimate pooled prevalence and conducted subgroup analyses based on WHO region, continent, publication year, specimen type, and biofilm detection method. Meta-regression and sensitivity analyses assessed heterogeneity and robustness. Publication bias was evaluated using Egger’s test and corrected with trim-and-fill analysis. The global pooled prevalence of biofilm-forming E. faecalis was 68.68% (95% CI: 61.33–76.02%), with significant heterogeneity (I² = 99.30%). By WHO region, prevalence ranged from 57.93% (95% CI: 41.01–71.85%) in South-East Asia to 73.66% (95% CI: 63.40–83.92%) in the Eastern Mediterranean. By continent, South America (all from Brazil) showed the highest prevalence at 89.79% (95% CI: 73.02–106.56%). Studies from 2021 to 2024 reported higher prevalence (76.18%, 95% CI: 66.25–86.11%) than those from 2015 to 2020. Among specimens, urine showed the highest prevalence (80.47%, 95% CI: 61.17–99.77%). Among biofilm-positive isolates, 47.92% (95% CI: 39.34–56.51%) were strong producers. Meta-regression identified WHO region (p = 0.005) and specimen type (p = 0.043) as significant sources of heterogeneity. Egger’s test indicated publication bias (p = 0.0066), but trim-and-fill analysis yielded a consistent adjusted prevalence of 68.08%. Biofilm formation is highly prevalent in E. faecalis clinical isolates globally, with substantial regional and specimen-based variation. These findings highlight the urgent need for standardized biofilm detection protocols, improved infection prevention and control, tailored antibiotic stewardship, and the development of anti-biofilm therapies to mitigate biofilm-associated resistance and enhance patient outcomes.

Infectious diseases are considered a major cause of death globally, accounting for one-third of all deaths. Traditionally, microbiological approaches to diagnose infectious diseases have been labor-intensive and time-consuming; molecular methods significantly improve on these constraints. DNA microarray is a novel and advanced diagnostic test for infectious disease that is designed for specific identification of a wide variety of organisms simultaneously. Microarray has various advanced applications in infectious disease diagnostics, including the 2019 pandemic COVID 19, detection of food-borne infectious agents, and detection of Neisseria meningitidis. The aim of this review is to provide updated application of DNA microarray techniques for the diagnosis of infectious diseases and to explore the development of new DNA microarray methods. In conclusion, DNA microarray techniques are the future rapid and accurate diagnostic tool for infectious disease diagnosis and detection of antimicrobial resistance.

Antimicrobial resistance (AMR) is a growing global health threat. Acinetobacter baumannii (A. baumannii) emerged as one of the most concerning critical priority pathogens due to its ability to develop resistance to multiple antimicrobial agents. In Ethiopia, the public health impact of AMR is increasingly significant, with A. baumannii responsible for a variety of infections. Although A. baumannii causes a range of infections in Ethiopian patients, the drug resistance status of the clinical isolates has not been thoroughly assessed. Therefore, this systematic review and meta-analysis aimed to determine the country-wide AMR of A. baumannii. This systematic review and meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We conducted a search of articles on PubMed, Web of Science, Science Direct, Scopes electronic databases, Google Scholar search engine, and institutional repositories/libraries for studies published between 2015 and 2024. Eligible studies on A. baumannii-related infections and AMR in Ethiopia were assessed for quality using the Joanna Briggs Institute (JBI) criteria. Data on study characteristics were extracted, and statistical analyses, including heterogeneity (Invers of variance), publication bias (Eggers test), and subgroup analyses, were performed using STATA 17.0. A random effect model was used to compute the pooled prevalence of AMR. This systematic review and meta-analysis of 26 Ethiopian studies (26,539 participants) found an A. baumannii prevalence of 3.99% (95% CI: 3.01–4.98%) and 9.13% of all bacterial infections (95% CI: 6.73–11.54%). The most common infections were surgical site infections, urinary tract infections, pneumonia, and sepsis. Pooled resistance to antibiotics varied, with amikacin showing the lowest resistance (20.27%) (95% CI: 11.51–29.03) and cefotaxime the highest (83.18) (95% CI: 71.87–94.48). A pooled multi-drug resistant (MDR) A. baumannii was found in 88.22% (95% CI: 82.28–94.15) of isolates, with regional and infection-type variations, particularly in higher prevalence in Oromia and Amhara regions and sepsis cases. This systematic review underscores the alarming rise of antimicrobial resistance in A. baumannii, particularly against carbapenems. The findings highlight a high prevalence of MDR A. baumannii and widespread extended-spectrum beta-lactamase production, with notable regional variations in resistance patterns. These high resistance rates reinforce A. baumannii as a critical global health threat, necessitating urgent interventions such as enhanced antimicrobial stewardship programs, improved infection control measures, and the development of alternative treatment strategies. Healthcare professionals, policymakers, and researchers must collaborate to mitigate the clinical and public health impact of this pathogen. This systematic review and meta-analysis was registered on PROSPERO (Registration ID: CRD42024623927).