Introduction: Rickettsia felis, a Gram-negative obligate intracellular prokaryotic organism, causes human infections with atypical clinical presentations, commonly including fever, fatigue, headache, and maculopapular rash. Case presentation: This study presents a rare case of pleural effusion (PE) associated with R. felis infection, confirmed through targeted next-generation sequencing (tNGS). The patient showed significant clinical improvement and resolution of PE following empirical moxifloxacin followed by pathogen-directed therapy with rifampicin and azithromycin, along with supportive measures for circulation and immune function. Conclusions: This case report aims to enhance early diagnosis and therapeutic strategies for R. felis infections by sharing the diagnostic and management experience.
Introduction: Pseudomonas aeruginosa is a common cause of nosocomial infection in both immunocompetent and immunocompromised individuals. It exhibits innate resistance to a wide range of antibiotics and threatens global public health as a silent pandemic. Methodology: From September 2024 to March 2025, 120 clinical specimens were collected from patients with infected burns of both genders and various ages at the Burn hospital in Duhok city, Iraq. The obtained Pseudomonas aeruginosa isolates were used for the molecular characterization of the virulence genes, the ExoS and Las B, by Polymerase Chain Reaction (PCR). Results: The overall prevalence of Pseudomonas aeruginosa was 37.5% (45/120), with a significantly higher rate among females than males (45.7% vs 26%). Furthermore, the highest rate of infection (55%) was among ages of > 20-30 years, while the lowest rate, 12.5% was among ages of < 1-10, with a highly significant difference (p = 0.001). All of the examined isolates were 100% (22/22) positive for Exo S and 95.5% (21/22) for Las B genes. Conclusions: This study underscores the high prevalence of these virulence genes among the Pseudomonas aeruginosa isolates from infected burns, indicating their clinical and epidemiological significance. Additionally, their phylogenetic relatedness highlights their pathogenic potential and role in the international dissemination of virulent lineages.
Introduction: Mpox has shown increasing incidence and geographic spread since its first identification in the Democratic Republic of the\001 Congo (DRC) in 1970. Methodology: We analyzed weekly mpox surveillance data reported from 2002-2022 in the DRC. Temporal trends were assessed using time-series decomposition to separate secular trends, seasonal patterns, and residual variation. Change-point analysis identified distinct transmission phases. Spatial trends were analyzed through thematic mapping of incidence rates across Health Zones.\001 Results: Between 2002 and 2022, a total of 55,072 suspected mpox cases and 1,297 deaths were reported, corresponding to an overall case fatality rate (CFR) of 2.4% and a mean CFR of 2.15% (95% CI: 1.8–2.5). Incidence increased progressively, with marked rises after 2010 and further intensification after 2015. Recurrent seasonal peaks were observed at the beginning of the year (February) and during mid-year (May–July). Change-point analysis identified four distinct transmission phases, during which annualized incidence increased from 0.78 to 2.67 cases per 100,000 population, alongside a steady geographic expansion from 56 to 159 health zones. By the most recent phase (2018–2022), approximately 30% of health zones nationwide had reported mpox cases. While CFRs declined during the intermediate phases, they increased again in recent years, reaching 2.63% in Phase IV. Conclusions: Mpox remains persistently endemic in the DRC, with progressive geographic expansion. These findings underscore the need for sustained surveillance, strengthened community engagement, and targeted prevention strategies embedded within a broader One Health framework to address zoonotic and ecological drivers of transmission.
Introduction: The most commonly used sample collection method for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is nasopharyngeal swab; however, sample collection, especially from pediatric patients, is difficult. Therefore, the aim of this study was to design a saliva collection strip and to compare the effectiveness of this strip with the nasopharyngeal swab. Additionally, the performance of different isolation procedures before real time quantitative polymerase chain reaction (RT-qPCR) were investigated and an in-house RT-qPCR assay was developed. Methodology: A total of 200 samples was collected from patients and 92 samples were confirmed as SARS-CoV-2 positive. In the first technique, nucleic acid from the samples were isolated using different isolation methods, and then analyzed by RT-qPCR. In the second technique, the samples were analyzed directly by RT-qPCR without any isolation process. Additionally, in-house RT-qPCR assay was performed and the results were compared with conventional RT-qPCR. Results: The cycle threshold (Ct) values were compared between the techniques, and very similar results were obtained with all of the methods. This reveals that both sample collection methods, both isolation methods, and both RT-qPCR assays had comparable accuracy. Conclusions: In this study, in-house optimization, validation, and integration of the SARS-CoV-2 assay with both isolation-based and extraction (direct lysis) workflows were compared. In addition, its compatibility with the newly designed saliva strip collection system was analyzed. Very similar results were obtained from all of the methods. Therefore, the sample collection strip and in-house assay can be useful tools for detecting SARS-CoV-2.
Introduction: Carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates are increasingly spreading in the community and pose a serious public health threat. Rapid and accurate detection of these isolates is therefore critical. This study aimed to evaluate the performance of combined disc method, the carbapenem inactivation method (mCIM) and its modifications. Methodology: A total of 100 K. pneumoniae isolates collected from various clinical samples between 2018 and 2021 were included. Carbapenemase production was investigated using the combined disc method, mCIM (19 mm and 22mm), and aCIM (19 mm and 22 mm). Carbapenemase types were determined using the combined disc method, eCIM, and mCIMplus. Resistance genes were detected by real-time PCR, which was used as the reference method to evaluate the performance of phenotypic tests. Results: For carbapenemase detection, the sensitivities of combined disc method, mCIM-19 mm, mCIM-22 mm, aCIM-19 mm, and aCIM-22 mm were 100%, 84.8%, 95.7%, 83.7% and 95.7%, respectively, while the specificities are 62.5%, 100%, 25%, 100%, and 62.5%. For carbapenemase species detection, the sensitivities of the combined disc method, eCIM-19 mm, eCIM-22 mm, and mCIMplus were 98,9%, 75.4%, 84% and 26.1%, respectively; the specificities were 62.5%, 48.8%, 42% and 100%. No significant differences were observed between the mCIM and aCIM tests. (p value:1 for 19 mm, p value:0.37 for 22 mm). Conclusions: The combined disc method provided the most effective balance of performance and practicality. However, phenotypic methods may be insufficient for isolates harboring multiple resistance genes.
Introduction: Bacterial vaginosis (BV) remains highly prevalent worldwide. Although vaginal pH has been suggested to be a good predictor of BV, findings are conflicting. This study investigated the prevalence and risk factors associated with BV and the association between BV and vaginal pH in women from Durban, South Africa. Methods: This was a cross-sectional study that included 150 pregnant and non-pregnant women. BV was diagnosed using Nugent scoring and vaginal pH was measured using Lovibond® pH strips. Vaginal pH results were compared with Nugent scores. Statistical analyses were performed in STATA 17.1 using 95% confidence intervals and a significance level of 0.05. Results: According to Nugent’s criteria, BV prevalence was 29.33%, while an additional 29.33% of the women had intermediate BV. Women aged 31–39 years were more likely to have BV than younger women (odds ratio [OR]: 7.27; 95% CI 1.40- 37.85; p = 0.018). Women with intermediate BV had a 2.4-fold higher likelihood of vaginal dysbiosis (OR: 2.42; 95% CI: 1.07-5.45; p = 0.033). Significant associations were observed between BV status and the presence of BVAB-1 (p = 0.016), BVAB-2 (p = 0.009), BVAB-3 (p = 0.048), Atopobium vaginae (p = 0.029), and Sneathia sanguinegens (p < 0.001). However, vaginal pH was not significantly associated with the prevalence of BV-associated microorganisms (p > 0.05). Conclusions: BV was common among women in Durban, South Africa; however, vaginal pH was not associated with BV or BV-associated bacteria, indicating that it was a poor predictor of BV in this population.
Introduction: Carbapenemase-producing Enterobacterales (CPE) have widely emerged as a global health threat due to the spread of resistance genes such as New Delhi metallo-β-lactamase (blaNDM) and oxacillinase-48-like β-lactamases (blaOXA-48-like). Data on the molecular epidemiology of CPE in northern Morocco remain limited. Hence, this study aimed to report the epidemiological profile of carbapenem-resistant Enterobacterales and their molecular analysis. Methodology: A prospective study was conducted from July 2024 to July 2025 at Mohammed VI University Hospital, Tangier. Ninety-two non-duplicate Enterobacterales isolates were collected across different departments. Species were identified via the matrix-assisted laser desorption/ionization - time-of-flight (MALDI-TOF MS) technique and antimicrobial susceptibility testing was performed according to the guidelines of the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Carbapenemase production was screened using GeneXpert® Carba-R (Cepheid, Sunnyvale, USA). Associations between clinical, microbiological, and molecular data were assessed using Chi square or Fisher’s exact tests. Results: Klebsiella pneumoniae dominated across all isolates (75/92; 81.5%), followed by Escherichia. coli (8/92; 8.7%). BlaNDM was found in 65/92 (70.6%), blaOXA-48-like in 17/92 (18.5%), and both in 10/92 (10.9%). Most cases occurred in neonatal (38%) and intensive care units (31.5%). Resistance exceeded 70% for several major antibiotics; 29.3% were colistin-resistant. Mortality was 46.7%. Diabetes (p < 0.01) and severe burns (p < 0.01) were significantly associated with carbapenemase carriage. Conclusions: CPE, especially NDM-producing Klebsiella pneumoniae, represent a major threat in northern Morocco, notably in neonatal and critical care units. Their high resistance and mortality highlight the urgent need for reinforced infection control, molecular surveillance, and rapid diagnostics.
Introduction: Sepsis epidemiology varies regionally. We aimed to characterise community-acquired sepsis in Chinese older adults and develop an evidence-based, cost-effective empirical therapeutic pathway tailored to local antimicrobial-resistance patterns. Methods: This single-centre, retrospective observational cohort study conducted at a tertiary hospital in Shanghai, China, enrolled 122 consecutive older adults (age ≥ 65 years) meeting Sepsis-3 criteria between June 2021 and May 2023. Microbiological data, antimicrobial-susceptibility profiles, clinical characteristics, and 28-day all-cause mortality were analysed. Multivariate logistic regression was used to identify independent risk factors for mortality. Results: Gram-negative bacteria predominated (54.9%) and showed high susceptibility to cefoperazone-sulbactam (85.0%). The 28-day mortality rate was 37.7%. Multivariate analysis identified increasing age (adjusted odds ratio [aOR] = 1.10 per year), need for intensive care unit admission (aOR = 6.65), mechanical ventilation (aOR = 5.78), and dialysis (aOR = 3.62) as independent predictors of mortality. Notably, adequate empirical antimicrobial therapy was not an independent protective factor in the adjusted model. A cost-effective clinical pathway with cefoperazone-sulbactam as the first-line empirical therapy and escalation based on clinical response was developed for use in resource-limited settings. Conclusions: The findings underscore the dominance of Gram-negative pathogens and the critical influence of host factors on survival among older adults with sepsis in China. They also provide a carbapenem-sparing, pragmatic, and sustainable management pathway for initial sepsis treatment in resource-limited settings, which can be replicated for antimicrobial stewardship in other regions with similar epidemiological profiles. The clinical effectiveness of this hypothesis-generating pathway requires validation in prospective, multicentre studies..
Introduction: Brucellosis is a zoonotic infection that is endemic in many regions, including Türkiye. Spondylodiscitis is one of its most significant complications. This study evaluated the association of hematologic parameters, particularly C-reactive protein (CRP) and the CRP-to-lymphocyte count (CRP/LC) ratio, with serological titers and magnetic resonance imaging (MRI)-confirmed spondylodiscitis, and explored their potential role as supportive markers for risk stratification and identifying patients who may benefit from further imaging. Methodology: This retrospective cross-sectional study analyzed 1,568 patients with positive Rose Bengal test results between 2014 and 2022. Hematologic and serologic data were evaluated, and imaging findings [MRI/computed tomography (CT)] were reviewed for spondylodiscitis. Serum tube agglutination (STA) titers ≥ 1/160 were considered as indicative of acute infection. Statistical methods included correlation, multiple linear regression, receiver operating characteristic (ROC) analysis, and non-parametric tests. Results: STA titers ≥ 1/160 were more frequent in males (68.87%) than females (29.69%) (p < 0.001). CRP, LC, and CRP/LC ratio were significantly higher in patients with elevated STA titers and MRI-confirmed spondylodiscitis. Correlations between hematologic markers and STA titers were generally weak to modest. Multiple linear regression identified CRP and LC as independent predictors of STA titer. ROC analysis showed that CRP (AUC: 0.67; area under the curve) and CRP/LC ratio (AUC: 0.66) had the highest discriminative performance. MRI-confirmed spondylodiscitis was detected in 2.3% patients. Conclusions: CRP and CRP/LC ratio appear to be useful supportive markers for identifying patients with high STA titers and MRI-confirmed spondylodiscitis and may help clinicians prioritize imaging studies in specific cases.
Objective: To evaluate the diagnostic performance and clinical utility of targeted third-generation sequencing (tTGS) for pathogen detection in community-acquired pneumonia (CAP), compared with targeted next-generation sequencing (tNGS) and conventional culture. Methodology: We conducted a real-world, retrospective study including 356 CAP patients who were tested in parallel with culture, tNGS, and tTGS. Diagnostic sensitivity, pathogen spectrum, mixed-infection detection, and antimicrobial resistance (AMR) gene profiling were compared across methods. Clinical relevance was assessed by analyzing treatment adjustments informed by sequencing results. Results: tTGS demonstrated the highest overall sensitivity (99.16%), surpassing tNGS (96.35%, p < 0.05) and culture (50.27%, p < 0.01). Across all samples, tTGS identified 135 microbial species — substantially more than tNGS (84 species) and culture (27 species) — including fastidious, rare, and slow-growing pathogens. tTGS also showed an improved ability to detect mixed infections (86.24% vs. 87.64% with tNGS; culture detected none). AMR gene detection was significantly higher with tTGS than with tNGS (58.99% vs. 48.88%, p = 0.008), and long-read sequencing enabled the identification of composite resistance patterns that tNGS missed. Among patients without underlying diseases, sequencing-guided therapeutic adjustment occurred in 67.87% of cases, with nearly 80% of AMR-positive patients demonstrating clinical improvement following regimen optimization. Conclusions: tTGS provides markedly enhanced pathogen detection, greater sensitivity, and more comprehensive AMR profiling than both tNGS and culture. Its strong performance in identifying mixed infections and actionable determinants of resistance supports its incorporation into clinical diagnostic workflows for CAP. Further large-scale, prospective studies are warranted to validate its clinical impact and optimize its integration into routine practice.
Objective: To determine the prevalence of toxoplasmosis in cardiac patients and investigate the relationship between toxoplasmosis and cardiac diseases. Methodology: The study included 170 patients followed up in the cardiology department (patient group) and 167 individuals without any disease who were not receiving any immunosuppressive treatment (control group). Blood samples obtained from the study participants were analyzed for anti-Toxoplasma gondii immunoglobulin G (IgG) levels via enzyme-linked immunosorbent assay. Results: Anti- T. gondii IgG was detected in 41.2% of the patient group and 29.3% of the control group. Statistical analysis showed a significant correlation between anti- T. gondii IgG seropositivity in the patient and control groups. In the patient group, anti- T. gondii IgG was detected in 65.7% of those with a history of myocardial infarction (MI), 49.4% of those undergoing coronary angiography, and 48.6% of those undergoing stenting. In the statistical evaluation of patients with a history of coronary angiography, stenting, and MI, and toxoplasmosis seropositivity, significant relationships were found separately (p = 0.016, p = 0.014, and p = 0.001, respectively). Conclusions: Patients with cardiac diseases were found to be at a higher risk for toxoplasmosis compared to healthy individuals. In individuals with cardiac diseases, it is recommended that patients should be monitored for toxoplasmosis at regular intervals and necessary precautions should be taken, considering that latent infection may be reactivated in case of immune system failure.
Ebola virus disease and Marburg virus disease are severe, highly lethal infections caused by filoviruses, characterized by rapid transmission, complex clinical management, and major socio-economic impact. A narrative review of recent outbreaks between 2021 and 2025 underscores persistent systemic gaps that compromise early detection and effective containment. The recurrence of Ebola and Marburg outbreaks demonstrates that, although progress has been made since the 2014-2016 West African epidemic, substantial vulnerabilities persist.
Introduction: Community-acquired pneumonia (CAP) remains a major cause of morbidity and mortality in elderly patients. Early identification of high-risk individuals is crucial for improving outcomes. Biomarkers derived from routine laboratory tests, such as the lactate / albumin (L/A) ratio, may provide valuable prognostic information. Methodology: This retrospective, two-center observational study included patients aged ≥ 65 years who were hospitalized with CAP between January 2021 and December 2024. Demographic characteristics, comorbidities, clinical severity scores, and laboratory parameters obtained at hospital admission were analyzed. Laboratory-derived ratios, including L/A, C-reactive protein/albumin (CRP/A), procalcitonin/albumin (PCT/A), and lactate dehydrogenase/albumin (LDH/A), were calculated. Receiver operating characteristic (ROC) analysis and logistic regression were performed to assess predictors of in-hospital mortality. Results: A total of 150 patients were included, of whom 24% died during hospitalization. Non-survivors had significantly higher comorbidity burden, quick sepsis-related organ failure assessment (qSOFA) scores, lactate levels, and biomarker-based ratios. The L/A ratio was significantly associated with mortality (p < 0.001) and demonstrated moderate diagnostic performance (area under ROC, AUC = 0.263), with relatively favorable sensitivity and negative predictive value. Among the evaluated clinical scores, qSOFA showed the most balanced discriminatory performance. Multivariate analysis identified baseline oxygen saturation, Glasgow coma scale, albumin, and lactate levels as independent predictors of mortality. Conclusions: The L/A ratio is a readily available biomarker associated with mortality in elderly patients with CAP. Although not a standalone predictor, it may serve as a complementary prognostic tool alongside established clinical severity scores, particularly during early patient assessment.
Background: This study aimed to determine the prevalence of hospital-acquired infections (HAIs), identify associated risk factors, and describe the microbiological profile of HAIs in a university hospital (UH) in central Tunisia during 2025. Methods: A prevalence study was conducted at a UH in Sousse, central Tunisia. Following the Centers for Disease Control and Prevention definitions, all infections occurring more than 48 hours after hospital admission were classified as HAIs and included in the study. Data collection included a one-day survey per department and a six-day prevalence assessment. Baseline characteristics, clinical features, isolated pathogens, and antimicrobial resistance profiles were recorded. Results: Among 255 eligible patients, 29 had at least one HAI, yielding a prevalence of 11.4%. Bloodstream infections and pneumonia were the most frequent HAIs (32.4% each). Gram-negative bacteria represented 67.4% of all isolates, with Klebsiella pneumonia and Acinetobacter baumannii being the most common (15.2% each). More than half of the isolates (59.4%) were multidrug resistant, including 53.8% of non-fermentative Gram-negative bacilli resistant to carbapenems and 73.3% of Enterobacterales resistant to third-generation cephalosporins. Multivariate analysis showed that prolonged hospital stay (> 10 days) was identified as an independent risk factor for HAIs (AOR = 8.08, 95% CI: 2.54-25.67, p< 0.001). Conclusions: Our findings indicate a high prevalence of HAIs and MDR pathogens. Strict adherence to infection control measures, combined with the implementation of an antibiotic stewardship program at the regional and national levels, is crucial to reducing infections and limiting the emergence of resistant strains.
Introduction: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a significant global health concern due to its high morbidity and mortality rates and limited treatment options. We investigated the molecular characteristics and co-occurrence of resistance genes in CRKP isolates from a tertiary hospital in Bangkok, Thailand. Methodology: Seventy-three non-repetitive CRKP isolates were collected from clinical specimens of hospitalized patients from August 2022 to January 2023. Identification was confirmed using standard microbiological tests and MALDI-TOF-MS. Antimicrobial susceptibility was assessed using the MicroScan system. PCR was employed to detect carbapenemase genes and extended-spectrum beta-lactamases (ESBLs). Results: The study revealed a high resistance rate among the CRKP isolates to cephalosporins, aminoglycosides, fluoroquinolone, and trimethoprim/sulfamethoxazole. Of the 73 CRKP isolates, 98.6% were susceptible to tigecycline, and 46.6% remained susceptible to ceftazidime-avibactam. Molecular analysis revealed that blaOXA-48-like (93.2%) and blaNDM-1 (43.8%) were the predominant carbapenemase genes. All isolates harbored the ESBL gene blaCTX-M-15. The co-occurrence of blaOXA-48-like and blaNDM-1 was observed in 39.7% of the isolates. Ward-specific analysis revealed the highest diversity and frequency of co-resistance gene profiles in isolates from the medical ward, while isolates from ICUs also exhibited complex gene combinations involving multiple ESBL and carbapenemase genes. Conclusions: This study reveals a high prevalence of blaOXA-48-like and blaNDM-1 genes among CRKP isolates in a tertiary hospital in Bangkok. The diversity of resistance profiles and the clustering of complex gene combinations, particularly in medical and ICU wards, underscore the need for continuous molecular surveillance and stringent infection control measures to manage the spread of CRKP in healthcare setting.
Introduction: Nosocomial infections (NIs) in the neonatal intensive care unit (NICU) are a significant cause of disability or death in preterm infants. This study focused on the bacteriological characteristics of NIs in preterm infants based on blood culture, and the factors related to Gram-negative bacterial infection. Methodology: This retrospective study was conducted at the NICU in Renmin Hospital of Wuhan University from January 2020 to June 2024. The patients were divided into Gram-negative and Gram-positive bacteria groups based on Gram staining results. Logistic regression analysis was performed to identify the factors influencing Gram-negative bacterial infection, and the diagnostic value was evaluated based on the area under the receiver operating characteristic curve (AUC). Results: A total of 54 strains (54/95, 56.84%) of Gram-positive bacteria and 41 strains (41/95, 43.16%) of Gram-negative bacteria were detected in the blood cultures of the 95 patients diagnosed with late-onset sepsis. The proportion of Gram-negative bacteria in the past 5 years exhibited a trend of initially decreasing and then increasing. Use of mechanical ventilation, decreased monocyte count, and elevated lactate levels were identified as factors predicting Gram-negative bacterial infection (p < 0.05). The AUC values of these factors for predicting Gram-negative bacterial infection were 0.56 (p < 0.05), 0.71 (p < 0.05), and 0.71 (p < 0.05), respectively. Conclusions: The proportion of Gram-negative bacterial infections showed a trend of initially decreasing and then increasing from 2020 to 2024. The use of mechanical ventilation, decreased monocyte counts, and elevated lactate levels were factors influencing Gram-negative bacterial infection.
Introduction: Healthcare-associated infections (HAIs) remain a major cause of morbidity and mortality in pediatric intensive care units (PICUs), particularly in the context of increasing antimicrobial resistance. This study aimed to evaluate the incidence of HAIs, causative microorganisms, antimicrobial resistance patterns, and temporal trends over a nine-year period in the PICU of a tertiary care hospital. Methodology: HAI data obtained through active surveillance between January 1, 2016, and December 31, 2024, were retrospectively analyzed. Patients who developed HAIs during their PICU stay were included. Diagnoses were established according to the National Healthcare-Associated Infections Surveillance Network (UHESA) criteria adapted from CDC definitions. Microorganisms were identified using the automated VITEK® 2 system (bioMérieux), and antimicrobial susceptibility testing was interpreted according to EUCAST criteria. Data were evaluated by calendar year and in three-year intervals. Results: No statistically significant change in HAI incidence was observed over the nine-year period (p = 0.56). Gram-negative bacteria were the most frequently isolated pathogens, particularly Klebsiella pneumoniae and Pseudomonas aeruginosa. Among Gram-positive organisms, Staphylococcus aureus and coagulase-negative staphylococci predominated, while Candida species were the most common fungal isolates. The mortality rate among patients with HAIs was 44.7%, markedly higher than the overall PICU mortality rate (1.72%). Resistance rates increased notably, especially for carbapenems and colistin, whereas resistance to linezolid and vancomycin remained limited. Conclusions: HAIs continue to represent a major clinical challenge in PICUs. Increasing resistance among Gram-negative pathogens highlights the urgent need for strengthened infection control strategies, continuous surveillance, and effective antimicrobial stewardship programs.
Introduction: Typhoid fever is caused by Salmonella enterica, which is a chronic health problem in endemic areas due to multidrug resistance and biofilm development. The stress adaptation and virulence regulatory gene phoP and the biofilm-associated gene bapA may represent molecular targets for anti-virulence interventions. In this study, S. Typhi isolates from blood samples were characterized for their antimicrobial sensitivity and biofilm formation, and the molecular impact of biosynthesized selenium nanoparticles (SeNPs) on phoP and bapA expression was assessed. Methodology: Biochemical analyses and 16S rRNA polymerase chain reaction (PCR) were performed on 92 blood samples identified 35 S. Typhi isolates. Antimicrobial susceptibility was evaluated by standard protocols. Biofilm-formation capacity was determined. SeNPs were obtained from E. coli by biological synthesis according to ultraviolet–visible (UV-vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses; at concentrations of 12.5–100 µg/mL. Differences in gene expression were quantified by quantitative reverse transcription real-time PCR. Results: All the isolates were resistant to ampicillin and ceftriaxone; susceptible to meropenem, ertapenem, trimethoprim–sulfamethoxazole, chloramphenicol, and tetracycline; and had variable sensitivity to ciprofloxacin. The isolates induced strong (57.1%) and moderate (40%) biofilm formation. The production of phoP and bapA were significantly inhibited by SeNPs treatment in a concentration-dependent manner, with maximal inhibition at 100 µg/mL (p = 0.0001); and exhibited a significant positive correlation for both genes (R = 0.899). Conclusions: Biosynthesized SeNPs effectively downregulate key virulence determinants in antibiotic-resistant S. Typhi, supporting their potential as adjunctive or alternative therapies capable of decelerating pathogenicity and biofilm-associated persistence.
Introduction: The aim of this study was to develop a rapid isothermal amplification assay for Vibrio cholerae. Methodology: Specific primers were designed following the guidelines of the National Center for Biotechnology Information (NCBI) database and based on the highly conserved sequence of the Vibrio cholerae virulence factor gene ctxA. A detection method was then developed using recombinase polymerase amplification (RPA). Sensitivity, specificity, clinical sample collection, and processing were calculated. Results: A rapid isothermal amplification system was developed, showing a detection capability of one copy per microliter. Specificity analysis against a panel of control strains yielded no false-positive results under the tested conditions. The presence of V. cholerae was detected in 9 fecal samples collected from 20 patients who were hospitalized with suspected cholera infection. Conclusions: This method can be an effective aid in the detection of bacteria in clinical samples.
