Bacterial Meningitis

Community-acquired bacterial meningitis has a high fatality rate, and survivors may have significant long-term neurologic sequelae, despite appropriate antibiotics. Although cerebral spinal fluid cultures and/or PCR testing are necessary to establish a definitive case of bacterial meningitis, antibiotic administration should never be delayed while waiting to obtain a lumbar puncture. Patients with suspected bacterial meningitis should be started on empiric antibiotics and adjunctive dexamethasone within an hour of presentation, with subsequent regimens targeted toward the identified pathogen. Vaccines are an important tool to minimize the risk of bacterial meningitis, and use should be encouraged by adults at higher risk.

Outbreak of Enterovirus D68 in Young Children, Brescia, Italy, August to November 2024

Enterovirus D68 (EV-D68) is responsible for a plethora of clinical manifestations ranging from asymptomatic infections to severe respiratory symptoms and neurological disorders. EV-D68 was first detected in children with pneumonia in 1962 and, from then, only sporadic cases were reported until 2014, when outbreaks were notified across the world. After the withdrawal of preventive measures against SARS-CoV-2, a significant increase in EV-D68 infections has been reported in 2021-2022. A surveillance program to evaluate the incidence of enterovirus/rhinovirus (EV/RV) infections was implemented at the Brescia Civic Hospital, Italy. Fifty-five EV/RV-positive respiratory samples, belonging to pediatric patients, were subjected to NGS. We observed that 61.8% of samples were positive for EV, with EV-D68 as the most prevalent genotype predominantly detected between August and November 2024. Phylogenetic analysis revealed that EV-D68 sequences formed two monophyletic clades corresponding to the A2 and B3 lineages, highlighting their recent introduction in Italy. Interestingly, 40% of pediatric EV-D68 infections were detected with at least one other EV/RV. Our study highlights the crucial role played by genomic surveillance of respiratory infections to monitor the circulation of emerging and re-emerging viruses, as well as their evolution. This will be fundamental to enable prompt intervention strategies.

Presence of Coliforms and Reduced Water Quality in the Second Biggest Reservoir in São Paulo, Brazil

(1) Background: The Guarapiranga reservoir, located in the metropolitan region of São Paulo (RMSP), plays an important role in supplying water to the population. However, the growing urbanization in the region, which has occurred in a disorderly manner and lacks basic sanitation infrastructure, has had a detrimental impact on the reservoir's conditions. The aim of this study was to evaluate the physicochemical parameters and detect coliforms to determine the water quality of the Guarapiranga reservoir, as well as to characterize the microbial diversity and antimicrobial-resistance genes (ARGs) present in the reservoir water. (2) Methods: Four sampling campaigns of the Guarapiranga reservoir were carried out between October 2020 and July 2022. Physicochemical analyses, and selective microbiological culture for coliforms, as well as the extraction of bacterial DNA for subsequent sequencing and search for ARGs were carried out. (3) Results: Analysis of the physicochemical results showed a progressive reduction in the quality of the reservoir's water, and the microbiological tests consistently showed the presence of Escherichia coli, Salmonella spp., Shigella spp. and Klebisiella spp. in the water samples collected from the reservoir. Analyses of the sequencing data showed the predominant presence of the phyla Proteobacteria, Cyanobacteria, Bacteroidetes, Verrucomicrobia, Planctomycetes, and 12 ARGs were detected in the reservoir. (4) Conclusions: The increase in sewage discharge, mainly due to the growth of irregular housing, has affected the quality of the water, as indicated by the physicochemical analysis and detection of coliforms and ARGs.

Challenges and Innovations in Pharmacovigilance and Signal Management During the COVID-19 Pandemic: An Industry Perspective

Vaccine marketing authorization holders (MAHs) are responsible for the conduction of global vaccine pharmacovigilance on their vaccine products. A safety signal is detected when a new adverse event (AE) or aspect of an AE occurs after exposure to the vaccine and warrants further investigation to determine whether a causal association may exist. Signal detection and evaluation (signal management) begins at the start of vaccine development, before an MAH submits an application for authorization to regulatory authorities, continues through the course of all clinical trials, and carries on beyond development into the post-marketing phase. As long as the vaccine remains authorized anywhere in the world, pharmacovigilance continues. During the time that the COVID-19 vaccine became widely available after authorization and approval, clinical trials were also ongoing, and therefore all clinical development and post-authorization safety information was closely monitored for safety by the MAH. MAH pharmacovigilance activities were adapted to manage the unprecedented volume of safety information that became available within a very short timeframe following worldwide vaccination campaigns. No vaccine had previously been administered to such a large number of individuals in such a short time, nor had there previously been a public health vaccine experience that was the subject of so many medical and non-medical writings. The MAH's COVID-19 vaccine signal detection methods included the continuous review of accruing clinical trial data and the quantitative and qualitative analyses of spontaneously reported experiences. Review of published and unpublished medical literature and epidemiology-based analyses such as observed vs. expected analysis based on reported adverse events following immunization (AEFIs) played key roles in pharmacovigilance and signal management. All methods of signal detection and evaluation have caveats, but when considered in totality, can advance our understanding of a vaccine's safety profile and therefore the risk-benefit considerations for vaccinating both individuals and large populations of people. All COVID-19 vaccines authorized for use were subject to an unprecedented level of pharmacovigilance by their individual MAHs, national regulatory authorities, public health organizations, and others during the years immediately following regulatory authorization and full approval. The intense worldwide focus on pharmacovigilance and the need for MAHs and regulatory/health authorities to quickly evaluate incoming safety information, spurred frequent and timely communications between national and regional health authorities and between MAHs and regulatory/health authorities, spotlighting a unique opportunity for individuals committed to patient safety to share important accruing safety information in a collegial and less traditionally formal manner than usual. The global pandemic precipitated by the SARS-CoV-2 virus created a significant impetus for MAHs to develop innovative vaccines to change the course of the COVID-19 pandemic. Pharmacovigilance also had to meet unprecedented needs. In this article, unique aspects of COVID-19 vaccine pharmacovigilance encountered by one MAH will be summarized.

Genetic evidence from Mendelian randomization links CD40 levels to increased risk of estrogen receptor-positive breast cancer

This study uses Mendelian randomization (MR) to investigate the causal roles of CD40 and CD40L in BC.Data from genome-wide association studies (GWAS) on BC (overall, ER-positive, and ER-negative subtypes) and CD40/CD40L levels were obtained from the IEU database. Causal associations were assessed using the inverse-variance weighted (IVW) method, with additional robustness checks performed via MR-Egger, weighted median, and weighted mode methods. Sensitivity analyses, including Cochran's Q test and MR-PRESSO, were conducted to assess heterogeneity and pleiotropy. Reverse MR analyses were also performed to examine if BC influences CD40/CD40L levels.A borderline significant association was found between CD40 levels and overall BC risk (IVW OR 1.027, 95% CI 1.000-1.054, p = 0.049), with a more robust association observed for ER-positive BC (OR 1.048, 95% CI 1.016-1.082, p = 0.003). No significant associations were found between CD40 levels and ER-negative BC. CD40L did not show any significant associations with BC. Reverse MR analysis indicated no causal effect of BC on CD40/CD40L levels. CD40 is causally associated with a borderline increase in overall BC risk and a more significant increase in ER-positive BC risk. These findings suggest a potential role for CD40 in BC, particularly in ER-positive cases.

Mechanistic modeling of Legionella in building water systems: A critical review on the essential factors

Modeling Legionella exposure from building water systems is valuable to inform water management plans, but accurate risk estimates require accounting for spatiotemporal variations in concentrations. This comprehensive literature review covers existing mathematical approaches for predicting Legionella fate and transport in building water systems and proposes a framework for advanced modeling considering all mechanisms influencing its presence in water and biofilm during different life-stages (e.g., within protozoan hosts). Current models include persistence of culturable cells in a heater, growth and decay throughout simplified hot water systems, concentrations linked to water age using fitted growth rates, and a calibrated model for a highly-monitored system. The challenges of modeling influencing factors are also discussed, including water demand, hydraulics, nutrient availability, pipe materials, temperature, and chemical disinfection. By contrasting laboratory and field observations with existing models, this review highlights knowledge gaps and data needs for integrating Legionella growth and persistence into hydraulics, water quality and, ultimately, exposure models to define minimal-risk design and operational practices.

Systematic review and meta-analysis of cytomegalovirus-associated adverse outcomes and healthcare resource utilization in hospitalized patients with inflammatory bowel disease

PURPOSE

Serious complications and unplanned healthcare utilization are reported among inflammatory bowel disease (IBD) hospitalizations with associated cytomegalovirus (CMV). The present systematic review and meta-analysis aimed to examine the in-hospital outcomes of CMV-related hospitalization in IBD patients.

METHODS

Electronic databases were systematically searched in PubMed, Web of Science (ISI), Scopus, Embase, and Google Scholar until February 2024. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. Cochran's Q test and I2 statistics were applied to evaluate potential heterogeneity across eligible studies. The random-effects model obtained pooled odds ratio (OR) estimates and associated 95% confidence intervals (CI).

RESULTS

Sixteen articles were included in the meta-analysis, encompassing 5120 IBD patients diagnosed with comorbid CMV infection. Our findings indicated that compared to IBD patients without CMV, those with both CMV and IBD had a longer hospital length of stay (LOS) (8.65 days longer; 95% CI: 6.96, 10.34; P < 0.01), a greater colectomy risk (OR = 2.26; 95% CI: 1.53, 3.34; P < 0.01), and higher in-hospital mortality (OR = 2.83; 95% CI: 1.92, 4.16; P < 0.01). However, the difference in hospital charges between the two groups was not statistically significant (P = 0.78). Sensitivity analysis using the leave-one-out approach revealed significant changes in hospital costs after excluding certain studies. Additionally, subgroup analyses showed significant differences based on IBD subtypes for surgery risk and LOS.

CONCLUSION

Our findings suggest that CMV infection is associated with poorer outcomes in hospitalized IBD patients, highlighting the importance of early detection and appropriate management of CMV infection in this population to improve clinical outcomes and reduce healthcare resource utilization.

Phenotypic heterogeneity defines B cell responses to repeated SARS-CoV-2 exposures through vaccination and infection

Long-lived humoral memory is key to durable immunity against pathogens yet remains challenging to define due to heterogeneity among antigen-reactive B cells. We addressed this gap through longitudinal sampling over the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccinations with or without breakthrough infection. High-dimensional phenotypic profiling performed on ∼72 million B cells showed that receptor-binding domain (RBD) reactivity was associated with five distinct immunoglobulin G (IgG) B cell populations. Two expressed the activation marker CD71, both correlated with neutralizing antibodies, yet the one lacking the memory marker CD27 was induced by vaccination and blunted by infection. Two were resting memory populations; one lacking CD73 arose early and contributed to cross-reactivity; the other, expressing CD73, arose later and correlated with neutralizing antibodies. The fifth, a rare germinal center-like population, contributed to recall responses and was highly cross reactive. Overall, robust and distinct responses to booster vaccination overcame the superiority of hybrid immunity provided by breakthrough infection.

Direct amplification and sequencing of enterovirus genomes from clinical and wastewater samples reveals uncommon virus types in Cameroon

Knowledge about the genetic diversity of enteroviruses in sub-Saharan Africa remains biased by the fact that it has mainly been described through the characterization of specimens isolated in cell cultures. The aim of this study was to characterize enteroviruses that circulate among humans in Cameroon by focusing more specifically on respiratory enteroviruses and on enteroviruses that are non-cultivable or non-cytopathogenic in standard cell lines. For this purpose, RNA was extracted from nasopharyngeal swabs, stool suspensions, and sewage concentrates collected in Cameroon from January 2018 to December 2019, and the RNA extracts were subjected to molecular screening to detect enterovirus genomes, which were subsequently sequenced using Illumina technology. Overall, 81 strains of 32 virus types were identified. Most of the strains (61.7%) belonged to the species Enterovirus coxsackiepol, followed by members of the species Enterovirus betacoxsackie (21%), Enterovirus alphacoxsackie (14.8%), and Enterovirus deconjuncti (2.5%). Almost all of the strains were found in sewage concentrates (79%) and stool suspensions (18.5%). Only two EV-D68 strains were identified in nasopharyngeal swabs. Interestingly, several virus types that have rarely been reported were detected, including non-cultivable/non-cytopathogenic EV-C strains, among which was a new virus type assigned as EV-C119. These results highlight the fact that virus isolation and unbiased cell-culture-free approaches complement each other to provide a more complete view of the enterovirus landscape in humans.

Current methods in the diagnosis of invasive meningococcal disease

Invasive meningococcal disease (IMD) remains a significant health concern due to its global distribution, potential for epidemic spread, unpredictable nature, rapid progression, and high mortality rates or permanent sequelae. The global elimination of meningococcal illness via immunization is a primary objective of the World Health Organization's strategy to defeat meningitis by 2030. Timely recognition of meningococcal infection and immediate, precise, and specific identification of Neisseria meningitidis are essential for optimal clinical management and enhanced outcomes, monitoring evolving meningococcal epidemiology, detecting outbreak activity, and providing an effective public health response. Clinical findings, microscopic findings, Gram stains, and cultures are traditional and widely used diagnostic methods for the definition of IMD, despite some disadvantages. Real-time polymerase chain reaction (rt-PCR) and whole genome sequencing (WGS) are more accurate techniques for the identification of N. meningitidis and subsequent investigation; however, their cost and limited availability present issues. WGS has numerous uses, including strain characterization, population genomics, antibiotic resistance monitoring, and outbreak investigation. New-generation molecular technologies have been and will be used for designing meningococcal vaccines, as well as to monitor dynamic molecular meningococcal seroepidemiology. Microbiology reference laboratories are important, and the digital records and expertise they provide benefit public health for N. meningitidis, as well as other pathogens. While there has been significant progress in the development of meningococcal infection diagnostic tools, it is probable that a combination of approaches or new strategies will still be necessary. The goal of this review was to evaluate the current methods for diagnosing IMD and to discuss diagnostic challenges in practice.

Long-lasting antibody B-cell responses to SARS-CoV-2 three years after the onset of the pandemic

Immune memory is essential for the effectiveness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. In the current context of the pandemic, with a diminished vaccine efficacy against emerging variants, it remains crucial to perform long-term studies to evaluate the durability and quality of immune responses. Here, we examined the antibody and memory B-cell responses in a cohort of 113 healthcare workers with distinct exposure histories over a 3-year period. Previously infected and naive participants developed comparable humoral responses by 17 months after receiving a full three-dose mRNA vaccination. In addition, both maintained a substantial SARS-CoV-2-reactive memory B-cell pool, associated with a lower incidence of breakthrough infections in naive participants. Of note, previously infected participants developed an expanded SARS-CoV-2-reactive CD27-CD21- atypical B-cell population that remained stable throughout the follow-up period. Thus, previous SARS-CoV-2 infection differentially imprints the memory B-cell compartment without compromising the development of long-lasting humoral responses.

Development and implementation of restrictive platelet transfusion thresholds in a neonatal intensive care unit

OBJECTIVE

Thrombocytopenia is a common problem affecting preterm neonates. Recent studies show increased morbidity and mortality with liberal platelet transfusion thresholds. We sought to standardize thrombocytopenia management through a transfusion guideline to reduce excessive transfusions.

STUDY DESIGN

We developed and implemented a guideline using PDSA cycles for infants with birth weights <1000 grams. Platelet transfusions were classified as indicated or non-indicated per the guideline. Severe (grade 3 or 4) intraventricular hemorrhage and pulmonary hemorrhage rates were balancing measures.

RESULTS

We analyzed 101 infants pre-guideline and 96 infants post-guideline. The mean monthly non-indicated transfusions significantly decreased from 13.0 to 2.0, respectively (p-value < 0.01). Incidence of severe grade IVH and pulmonary hemorrhage remained stable.

CONCLUSION

Rapid implementation of an evidence-based, restrictive platelet transfusion guideline significantly reduced non-indicated platelet transfusions without a concomitant increase in major bleeding events.

Natural and induced immune responses in oral cavity and saliva

This review comprehensively explores the intricate immune responses within the oral cavity, emphasizing the pivotal role of saliva in maintaining both oral and systemic health. Saliva, a complex biofluid, functions as a dynamic barrier against pathogens, housing diverse cellular components including epithelial cells, neutrophils, monocytes, dendritic cells, and lymphocytes, which collectively contribute to robust innate and adaptive immune responses. It acts as a physical and immunological barrier, providing the first line of defense against pathogens. The multifaceted protective mechanisms of salivary proteins, cytokines, and immunoglobulins, particularly secretory IgA (SIgA), are elucidated. We explore the natural and induced immune responses in saliva, focusing on its cellular and molecular composition. In addition to saliva, we highlight the significance of a serum-like fluid, the gingival crevicular fluid (GCF), in periodontal health and disease, and its potential as a diagnostic tool. Additionally, the review delves into the impact of diseases such as periodontitis, oral cancer, type 2 diabetes, and lupus on salivary immune responses, highlighting the potential of saliva as a non-invasive diagnostic tool for both oral and systemic conditions. We describe how oral tissue and the biofluid responds to diseases, including considerations to periodontal tissue health and in disease periodontitis. By examining the interplay between oral and systemic health through the oral-systemic axis, this review underscores the significance of salivary immune mechanisms in overall well-being and disease pathogenesis, emphasizing the importance of salivary mechanisms across the body.

BA.1 breakthrough infection elicits distinct antibody and memory B cell responses in vaccinated-only versus hybrid immunity individuals

Immune memory is influenced by the frequency and type of antigenic challenges. Here, we performed a cross-sectional comparison of immune parameters following a BA.1 breakthrough infection in individuals with prior hybrid immunity (conferred by infection and vaccination) versus those solely vaccinated in a cohort of health care workers in Lyon, France. The results showed higher levels of serum anti-receptor binding domain (RBD) antibodies and neutralizing antibodies against BA.1 post-infection in the vaccine-only group. Individuals in this group also showed a decrease in memory B cells against the ancestral strain but an increase in those specific and cross-reactive to BA.1, suggesting a more limited immune imprinting. Conversely, hybrid immunity prevents the decrease in antibody dependent cellular cytotoxicity (ADCC) response, possibly by limiting IgG4 class-switching and enhanced anti-N responses post-infection. This highlights that BA.1 breakthrough infection induces different immune responses depending on prior history of vaccination and infection, which should be considered for further vaccination guidelines.

The composition of single-donor apheresis platelet concentrates is influenced by the age of the donor

The aging population often faces health issues that sometimes necessitate transfusions. Transfusion services are increasingly concerned about the rising number of transfusions and the aging donor population, as both factors are crucial in maintaining the quality of blood donations. In this context, our study aims to measure the bioactive molecule cytokine levels in single donor apheresis platelet concentrates (SDA-PC) based on the donor's age and to determine whether these cytokines, in conjunction with the donor age, could contribute to transfusion adverse reactions (AR). Our findings indicate that well-known platelet molecules such as sCD62P, as well as IL-13, ADAMTS13, MIP-1α, NGAL, MCP-3, HSAA, GDF-15, CX3CL1, and MDC, were present in SDA-PC. Levels of MIP-1α, GDF-15, and sCD62P increased with donor aging, whereas levels of MDC decreased. In conclusion, most of the cytokine levels detected were elevated in cases of AR and with increasing donor age. Notably, GDF-15 was the only cytokine that showed a positive correlation with age in the context of AR.

Intranasal spike and nucleoprotein fusion protein-based vaccine provides cross-protection and reduced transmission against SARS-CoV-2 variants

The effectiveness of intramuscular vaccines aimed at preventing severe COVID-19 remains limited due to waning immunity and the emergence of novel variants. Next-generation vaccines are needed for broader protection and blocking virus transmission. Here, we rationally designed an original nasal subunit vaccine composed of a fusion protein (SwFN) made of Wuhan spike and nucleoprotein combined with biocompatible mucosal nanocarriers (Nc). In mouse model, the nasal Nc-SwFN vaccine elicited multivalent serum and mucosal neutralizing antibodies. Robust spike and nucleoprotein cross-reactive immunity against variants was induced with a predominant phenotype of resident memory T cells in the lungs. Moreover, Nc-SwFN led to protective responses against Wuhan and Delta infection in relevant models with an absence of morbidity, mortality, and virus dissemination in the lungs and brain. Finally, Nc-SwFN drastically reduced host-to-host transmission. These promising results underscore the advantages of the nasal Nc-SwFN approach as a broad-spectrum vaccine candidate against current and emerging SARS-CoV-2 variants.

Kalman Filter-Based Epidemiological Model for Post-COVID-19 Era Surveillance and Prediction

In the post-COVID-19 era, the dynamic spread of COVID-19 poses new challenges to epidemiological modelling, particularly due to the absence of large-scale screening and the growing complexity introduced by immune failure and reinfections. This paper proposes an AEIHD (antibody-acquired, exposed, infected, hospitalised, and deceased) model to analyse and predict COVID-19 transmission dynamics in the post-COVID-19 era. This model removes the susceptible compartment and combines the recovered and vaccinated compartments into an "antibody-acquired" compartment. It also introduces a new hospitalised compartment to monitor severe cases. The model incorporates an antibody-acquired infection rate to account for immune failure. The Extended Kalman Filter based on the AEIHD model is proposed for real-time state and parameter estimation, overcoming the limitations of fixed-parameter approaches and enhancing adaptability to nonlinear dynamics. Simulation studies based on reported data from Australia validate the AEIHD model, demonstrating its capability to accurately capture COVID-19 transmission dynamics with limited statistical information. The proposed approach addresses the key limitations of traditional SIR and SEIR models by integrating hospitalisation data and time-varying parameters, offering a robust framework for monitoring and predicting epidemic behaviours in the post-COVID-19 era. It also provides a valuable tool for public health decision-making and resource allocation to handle rapidly evolving epidemiology.

A quantum mechanics-based framework for infectious disease modeling

Traditional infectious disease models often use fixed compartments to represent different states of individuals. However, these models can be limited in accurately reflecting real-world conditions of individuals. In this study, we integrate quantum mechanics into infectious disease modeling, developing a quantum mechanics-based model that effectively addresses the limitations of traditional compartmental models and introduces a novel approach to understanding disease dynamics. Firstly, we examined the individual infection process and the model's evolutionary dynamics, deriving both the disease-free equilibrium point and the model's basic reproduction number. Secondly, the proposed model is simulated on a quantum circuit. The simulation results are utilized to analyze the model's parameter sensitivity and verify its rationality. The results indicate that the model's predictions align with the general patterns of viral transmission and are capable of replicating the structural attributes of compartmental models. Finally, we apply the model to simulate the spread of COVID-19. The observed similarity between the simulated results and actual infection trends demonstrates the model's effectiveness in accurately capturing viral transmission dynamics. Comparative experiments show that the proposed model significantly improves accuracy over traditional models. By leveraging quantum mechanics, our method offers a fresh perspective in infectious disease modeling, broadening the application of quantum mechanics methodologies in understanding information propagation within the macroscopic world.

Associations between hospital structure, infection control and incidence of hospital-acquired viral respiratory infections: a 10-year surveillance study

BACKGROUND

Protecting patients from hospital-acquired viral respiratory infections is a major challenge, but the hierarchy of measures to achieve this is not yet completely clear.

AIM

To describe the epidemiology of hospital-acquired viral respiratory infections and associations with structural hospital factors and adherence to infection control protocols.

METHODS

Retrospective cohort study conducted over 10 consecutive years (2014-2023) within 27 hospital wards in a 900-bed university hospital in Paris, France. All hospitalized adult patients who were tested for at least one virus on a respiratory sample during their stay were included. Structural factors (percentage of double occupancy rooms) and adherence to infection control protocols by healthcare workers (measured by consumption of alcohol-based hand sanitizer and of facemasks) were included as predictors in the model.

MAIN OUTCOME AND MEASURE

Incidence of hospital-acquired viral respiratory infections, defined by a positive PCR test for at least one respiratory virus, performed at least 5 days after hospital admission. Data were analyzed on ward-year aggregated data, with a linear mixed-effects model.

FINDINGS

Overall, 183 994 viral PCR tests were performed over the study period. Incidence of hospital-acquired viral respiratory infections was 0.57/1000 hospital-days. After adjustment on other factors (mean length of stay, use of PCR testing), incidence of hospital-acquired viral respiratory infections in a given ward was significantly associated with: the incidence of community-acquired viral respiratory infections among patients admitted to the ward (+ 0.10/1000 hospital-days per each additional point of incidence; P < 0.001), the number of double-occupancy rooms (+ 0.04/1000 hospital-days per each 10%-increase of double-occupancy rooms; P = 0.03) and masks consumption (+ 0.33/1000 hospital-days per 10 additional masks used per day; P = 0.04). Similar results were found for double-occupancy rooms (+ 0.01/1000 hospital-days per each 10%-increase of double-occupancy rooms; P = 0.012) in the sub-group analysis of influenza cases.

CONCLUSION

In a given hospital ward, the incidence of community-acquired cases and the proportion of double-occupancy rooms are independently associated with the incidence hospital-acquired viral respiratory infections.

Predictive Factors of Cytomegalovirus Colonic Reactivation in Patients with Active Ulcerative Colitis

Cytomegalovirus (CMV)-associated colitis reflects the adverse impact of CMV reactivation on ulcerative colitis (UC). Its diagnosis requires the detection of viral markers in intestinal biopsies sampled during endoscopy, which may constitute invasive and expensive analyses. Moreover, less than 30% of acute flare-ups in steroid refractory UC are associated with CMV colitis. This retrospective study aimed to identify non-invasive factors that are predictive of CMV reactivation, and was conducted from 2014 to 2019 in a cohort of UC patients consulting at the University Hospital of Saint-Etienne, France. Patient characteristics, disease activity, immunosuppressive treatment and tissue CMV DNA load were collected at the time of UC relapse. Factors potentially associated with CMV reactivation were analyzed through a multivariate analysis. A total of 173 UC patients providing 323 pairs of intestinal biopsies were analyzed. In the CMV seropositive subgroup, a Mayo endoscopic score ≥2 (OR 2.553, 95% CI 1.353-4.818, p = 0.004) was identified as a predictive factor of CMV colitis in the multivariate analysis; in contrast, biological parameters exhibited no predictive value. In addition, the use of anti-TNFα monoclonal antibodies was associated with a reduced risk of CMV reactivation (OR 0.384, 95% CI 0.158-0.935, p = 0.035). Intestinal biopsies appear to be unavoidable for assessing disease activity and CMV reactivation in UC patients.

Sex-dependent gastrointestinal colonization resistance to MRSA is microbiota and Th17 dependent

Gastrointestinal (GI) colonization by methicillin-resistant Staphylococcus aureus (MRSA) is associated with a high risk of transmission and invasive disease in vulnerable populations. The immune and microbial factors that permit GI colonization remain unknown. Male sex is correlated with enhanced Staphylococcus aureus nasal carriage, skin and soft tissue infections, and bacterial sepsis. Here, we established a mouse model of sexual dimorphism during GI colonization by MRSA. Our results show that in contrast to male mice that were susceptible to persistent colonization, female mice rapidly cleared MRSA from the GI tract following oral inoculation in a manner dependent on the gut microbiota. This colonization resistance displayed by female mice was mediated by an increase in IL-17A+ CD4+ T cells (Th17) and dependent on neutrophils. Ovariectomy of female mice increased MRSA burden, but gonadal female mice that have the Y chromosome retained enhanced Th17 responses and colonization resistance. Our study reveals a novel intersection between sex and gut microbiota underlying colonization resistance against a major widespread pathogen.

Assessing the Utility of Broad-Acting Inhibitors as Therapeutics in Diverse Venoms

Examination of venom constituent bioactivities from diverse venomous animals shows certain highly conserved classes, including enzymes (e.g., phospholipases and metalloproteinases) and pore-forming proteins. While antivenoms targeting other unique and lethal venom components have proven to be life-saving, venom-enzyme-driven tissue damage and morbidity persists. Broad-acting enzyme inhibitors demonstrate the potential to augment antivenom approaches. In this study, we investigate the potential utility of certain broad-acting inhibitors in cubozoa for the first time. Fluorogenic assays were used to determine the phospholipase A2 (PLA2) and matrix metalloproteinase (MMP) activity of the Hawaiian box jellyfish, Alatina alata, and this was compared to representative elapid, viper, and bee venoms. In vitro, evaluation of selected small-molecule inhibitors demonstrated the ability and feasibility of the broad-acting therapeutic doxycycline, which inhibited the PLA2 and MMP activity of A. alata (approximately 50% reduction at 0.1 mM (95% CI 0.06-0.15) and 2.1 mM (95% CI 1.4-3.0), respectively), in addition to both snake venoms. Additionally, copper gluconate broadly inhibited the PLA2 activity of bee, snake, and jellyfish venoms. While all venoms are complex mixtures of bioactive molecules, these studies demonstrate that targeting common class components with broad-acting inhibitors shows promise in clinical and preclinical management.

Diagnostic and Prognostic Value of Hematological Parameters in Necrotizing Enterocolitis: A Systematic Review

Background/Objectives: Necrotizing enterocolitis (NEC) is a severe, potentially fatal gastrointestinal disease that primarily affects preterm neonates, especially those with very low birth weight (<1500 g). Despite extensive research, its pathophysiology remains unclear, with NEC considered a spectrum of disorders driven by systemic inflammation, microbiota dysregulation, and intestinal hypoxic injury. Diagnosis is challenging due to its subtle presentation and reliance on clinical and radiographic findings, underscoring the urgent need for reliable early biomarkers. Complete blood count (CBC) is one of the most frequently performed laboratory tests in neonatal care, providing valuable insights associated with hematologic alterations associated with NEC. Given its cost-effectiveness, accessibility, and rapid turnaround time, CBC parameters have been increasingly investigated for their diagnostic and prognostic potential in NEC. This systematic review consolidates existing evidence on the diagnostic and prognostic utility of CBC parameters in NEC, examining their association with disease onset, progression, and outcomes. Methods: A systematic review of the literature in PubMed and Scopus databases was conducted, between February 25 and December 2024. Results: Following a PRISMA-compliant search strategy, 77 eligible studies were included, analyzing data from 295,195 neonates, of whom 14,570 had NEC. Among the 77 studies, 17 examined NEC-associated mortality as a primary outcome, while 13 studies focused on the development of predictive models incorporating CBC parameters alongside other clinical and laboratory data to assess NEC severity and prognosis in neonates. The findings highlight the potential of CBC-derived markers to facilitate early NEC detection and risk stratification. However, variations in study design and diagnostic criteria highlight the need for prospective studies to validate their clinical use. Conclusions: Despite advancements in understanding NEC, its diagnosis remains challenging due to the absence of fully reliable biomarkers. CBC parameters show promise in offering early diagnostic and prognostic insights. However, further validation is needed for their routine integration into NICU practice. Given the persistent challenges in NEC diagnosis and management, our findings highlight the necessity for integrated scoring systems that combine hematologic, clinical, and radiologic data to enhance early detection and optimize neonatal care. Further research is essential to refine these predictive models, enabling timely interventions and improving survival rates in NEC-affected neonates.

Sialylated glycoproteins bind to Siglec-9 in a cis manner on platelets to suppress platelet activation

BACKGROUND

The endogenous negative regulation of platelets is important in preventing spontaneous thrombosis, while the mechanism of homeostasis is incompletely understood.

OBJECTIVES

In this study, we aimed to explore whether Siglec-9 plays a negative regulative role and identify the ligand of Siglec-9 on platelets.

METHODS

To determine the role of Siglec-9 on platelets, platelet factor 4-cre:Siglec-Eflox/flox knockout mouse model and human platelet in vitro culture system were used. Furthermore, recombinant glycoprotein (GP) of Siglec-9 ligand on platelets was expressed and used.

RESULTS

We found that Siglec-E conditional knockout can lead to significant increase in platelet coagulation activities both in vivo and in vitro, which strongly suggests that Siglec-9/E plays an inhibitory physiological role in platelet activation. Siglec-9 ligand is an O-link GP with an α2,3-linked sialic acid terminal structure, and the protein carrier of the ligand is mucin-like region of GPIbα. Our data further showed that the ligands on platelets could not engage Siglec-9 on other cells via trans-binding, which indicates that the ligands on platelets play a self-modulation role. Furthermore, we provided evidence that the activation of Siglec-9 pathway with exogenous specific ligands could inhibit the activity of platelets. These data demonstrate a previously unanticipated role for GPIbα in inhibiting platelet activation and provide a novel mechanism for the homeostasis of platelets.

CONCLUSIONS

We conclude that the cis-binding between mucin-like region of GPIbα and Siglec-9 acts as a "parking brake" on platelet activation. This finding provides a potential druggable target for novel antiplatelet medicine.

Sterile production of interferons in the thymus

T-cell central tolerance is controlled by thymocyte TCR recognition of self-peptides presented by thymic APCs. While thymic epithelial cells are essential for T-cell central tolerance, a variety of other traditional APCs also play critical roles in T-cell selection. Similar to how peripheral APCs require activation to become effective, thymic APCs also require activation to become tolerogenic. Recent studies have identified IFNs as an essential factor for the activation and generation of an optimally tolerogenic thymic environment. In this review, we focus on interferon (IFN) production within the thymus and its effects on thymic APCs and developing thymocytes. We also examine the importance of T-cell tolerance to IFN itself as well as to interferon-stimulated proteins generated during peripheral immune responses.

The intersection of influenza infection and autoimmunity

The relationship between viral infection and autoimmune manifestations has been emerging as a significant focus of study, underscoring the intricate interplay between viral infections and the immune system. Influenza infection can result in a spectrum of clinical outcomes, ranging from mild illness to severe disease, including mortality. Annual influenza vaccination remains the most effective strategy for preventing infection and its associated complications. The complications arising from acute influenza infection are attributable not only to the direct effects of the viral infection but also to the dysregulated immune response it elicits. Notably, associations between influenza and various autoimmune diseases, such as Guillain-Barré Syndrome (GBS), Type 1 Diabetes (T1D), and antiphospholipid syndrome, have been reported. While viral infections have long been recognized as potential triggers of autoimmunity, the underlying mechanisms remain to be elucidated. Here, we described the pathophysiology caused by influenza infection and the influenza-associated autoimmune manifestations. Current advances on the understanding of the underlying immune mechanisms that lead to the potential strategies were also summarized.

Observational Study of Microbial Colonization and Infection in Neurological Intensive Care Patients Based on Electronic Health Records

Background/Objectives: Patients with central nervous system injuries who are hospitalized in intensive care units (ICUs) are at high risk for nosocomial infections. Limited data are available on the incidence and patterns of microbial colonization and infection in this patient population. Methods: To fill this gap, we performed an electronic health record-based study of 1614 chronic patients with brain injury admitted to the ICU from 2017 to 2023. Results: Among the infectious complications, pneumonia was the most common (n = 879; 54.46%). Sepsis was diagnosed in 54 patients, of whom 46 (85%) were diagnosed with pneumonia. The only pathogen that showed an association with the development of pneumonia and sepsis in colonized patients was Pseudomonas aeruginosa (pneumonia: p = 7.2 × 10-9; sepsis: p = 1.7 × 10-5). Bacterial isolates from patients with and without pneumonia did not differ in pathogen titer or dynamics, but patients with monomicrobial culture were more likely to develop pneumonia than patients with polymicrobial culture (1 vs. 2 pathogens, p = 0.014; 1 + 2 pathogens vs. 3 + 4 pathogens, p = 2.8 × 10-6), although the pathogen titer was lower in monoculture than in polyculture. Bacterial isolates from all patients and all culture sites showed high levels of multidrug resistance (Gram-negative bacteria: 88-100%; Gram-positive bacteria: 48-97%), with no differences in multidrug-resistant organism (MDRO) colonization and infection rates. Conclusions: Our results highlight the high burden of MDROs in neurological ICUs and provide novel ecosystem-based insights into mono- and polymicrobial colonization and infection development. These findings may be useful for developing strategies to protect against infections.

In vitro efficacy of aqueous PVP-iodine solution below 5% as alternative to preoperative antisepsis in ophthalmology as the basis for an in vivo study

PURPOSE

Pre-operative antisepsis of the conjunctiva is indicated prior to intraocular surgery to prevent post-interventional endophthalmitis. In Germany, antisepsis with 5% povidone-iodine (PI) aqueous solution is explicitly required prior to intravitreal injections (IVI), and also generally recommended for intraocular surgery. However, this concentration often leads to a foreign body sensation and an unpleasant burning in combination with dry eye symptoms. Postoperative eye pain, persistent corneal epithelial defects, and a risk of keratitis are further side effects. Due to the repetitive nature of IVI, these symptoms are particularly present in IVI patients. A reduced concentration may be favorable to decrease patient discomfort. A 1.25% PI solution does not increase the iodine concentration in the aqueous humor and is also used for prophylaxis of ophthalmia neonatorum and for preoperative antisepsis; in both cases the renal iodine excretion stays in a physiological range thus thyroid diseases are no contraindication for its use. Thus, the efficacy of reduced concentrations of PI should be evaluated in vitro.

METHODS

PI with dilutions below 5% (0.625 - 2.5% serial 1:2 dilution) was tested in vitro in a quantitative suspension assay and in a quantitative carrier test without and with addition of matrices to identify their antimicrobial effect against Staphylococcus epidermidis, Pseudomonas aeruginosa, Cutibacterium acnes and Candida albicans.

RESULTS

No differences in the antimicrobial effect was seen due to reduced concentrations of PI in comparison to a 5% solution. However, a trend was seen regarding the required contact time of the antiseptic solution.

CONCLUSION

The in-vitro tests have shown adequate antisepsis of 1.25% PI prior to intraocular surgery. However, it is important to pay attention to a sufficient contact time of the antiseptic of about 1 min before ophthalmologic intervention. In order to give final recommendations, in vivo testing is needed to build a robust data foundation.

The comprehensive insights into the B-cells-mediated immune response against COVID-19 infection amid the ongoing evolution of SARS-CoV-2

The antibody-mediated immune response is crucial for the development of protective immunity against SARS-CoV-2, the virus responsible for the COVID-19 pandemic. Understanding the interaction between SARS-CoV-2 and the immune system is critical because new variants emerge as a result of the virus's ongoing evolution. Understanding the function of B cells in the SARS-CoV-2 infection process is critical for developing effective and long-lasting vaccines against this virus. Triggered by the innate immune response, B cells transform into memory B cells (MBCs). It is fascinating to observe how MBCs provide enduring immune defence, not only eradicating the infection but also safeguarding against future reinfection. If there is a lack of B cell activation or if the B cells are not functioning properly, it can lead to a serious manifestation of the disease and make immunisation less effective. Individuals with disruptions in the B cells have shown increased production of cytokines and chemokines, resulting in a poor prognosis for the disease. Therefore, we have developed an updated review article to gain insight into the involvement of B cells in SARS-CoV-2 infection. The discussion has covered the generation, functioning, and dynamics of neutralising antibodies (nAbs). Furthermore, we have emphasised immunotherapeutics that rely on nAbs.

The Relationship Between Potential Listeria monocytogenes Exposure and Diet Quality and Dietary Intake During Pregnancy: A Cross-Sectional Analysis in Australian Women

BACKGROUND

Research conducted over two decades ago indicated that more frequent consumption of foods potentially harbouring Listeria monocytogenes is associated with higher nutrient intakes but also higher risk of miscarriage. However, the influence of potential exposure to Listeria monocytogenes on pregnant women's diet quality is yet to be examined. Additionally, advancements in agricultural practices and food consumption trends in recent years may have led to changes in pregnant women's dietary intake. Therefore, the present study aimed to evaluate the associations between potential L. monocytogenes exposure and dietary quality, and dietary intake in two contemporary cohorts of pregnant women in Australia.

METHODS

A secondary analysis of two combined pregnancy cohorts of women aged ≥ 19 years with a singleton pregnancy from the Newcastle, New South Wales (n = 441) and Perth, Western Australia (n = 1197) was conducted. Potential L. monocytogenes exposure was estimated by the Listeria Food Exposure Score (LFES), dietary intake was assessed using the Australian Eating Survey and diet quality using the Australian Recommended Food Score. Pearson's correlation and linear regression analyses were performed to estimate the associations between potential L. monocytogenes exposure and dietary quality and intake, with adjustment for potential confounders.

RESULTS

Data from 1638 women (mean [SD] age 32.0 [5.0] years, 57.8% born in Australia) were included. The median (IQR) gestational age was 35 (34-36) weeks and 43.5% of women had no prior pregnancies. A higher LFES (i.e., more frequent consumption of potential food sources of L. monocytogenes) was significantly associated with higher diet quality score (r = 0.60, p < 0.001), higher intakes of nutrient-dense core foods (r = 0.11-0.43, p < 0.001), and higher micronutrient intakes (r = 0.24-0.52, all p < 0.001).

CONCLUSION

More frequent consumption of foods that potentially harbour Listeria monocytogenes is associated with higher diet quality and nutrient intakes. Further research is needed to identify how to support women to achieve optimal diet quality and nutrient intakes while simultaneously minimising risk of listeriosis.

Broad Mucosal and Systemic Immunity in Mice Induced by Intranasal Booster With a Novel Recombinant Adenoviral Based Vaccine Protects Against Divergent Influenza A Virus

The development of broad-spectrum universal influenza vaccines and optimization of vaccination strategies to address the threats posed by pandemics and emerging influenza viruses are critical for public health. In this study, an adenovirus type 5 vector-based influenza vaccine carrying the hemagglutinin (HA) stem of H1, HA stem of H3, and neuraminidase (NA) of N1 from the influenza virus was constructed. Immune responses were evaluated in mice using various vaccination strategies: prime-only (intramuscular [IM] or intranasal [IN]) and prime-boost (IM + IN). Compared with the prime-only strategy, the prime-boost strategy significantly enhanced the systemic immune response, inducing higher levels of antigen-specific IgG, mucosal IgA, and T cell immunity in the spleen and lungs. Furthermore, the IN boosting strategy provided complete protection in mice challenged with the H1N1-PR8, rgH3N2-X31, and rgH5N1-Vietnam viruses, significantly reducing viral loads in the lungs and alleviating lung tissue pathologies. In conclusion, this study elucidates potential avenues for the development and application of universal influenza vaccines using customized mucosal boosting strategies.

Synergistic effects of zP-1 phage and ampicillin against methicillin-resistant Staphylococcus aureus isolated from hospital staff

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) strains are a major cause of hospital-acquired infections, exacerbated by increasing antibiotic resistance.

AIM

This study aimed to isolate bacteriophages targeting MRSA and evaluate their antimicrobial activity in combination with antibiotics.

METHODS

Nasal samples from hospital staff (n = 50) were used to isolate MRSA strains, and sewage samples were processed for phage isolation using the double agar overlay technique. The microtitration plate method evaluated the synergistic effects of isolated phages and antibiotics.

RESULTS

Out of 50 samples, 11 MRSA strains were positive, showing high resistance to multiple antibiotics, including oxacillin (95%), and vancomycin (85%). Phage zP-1, belonging to the Myoviridae family, exhibited > 90% lytic activity, stable across temperatures (20-50 °C) and pH (6-8). A statistically significant synergistic effect was observed at a MIC of 0.137 μg/ml for gentamicin (p-value 0.02).

CONCLUSION

These findings suggest that phage-antibiotic synergy may offer a promising strategy to combat MRSA infections, warranting further in vivo studies to assess its clinical potential.

Clinical impact and safety of brain biopsy in unexplained central nervous system disorders: a real-world cohort study

OBJECTIVE

A substantial part of central nervous system (CNS) disorders remains unexplained, despite various new and minimally invasive diagnostic techniques. Within this rapidly developing diagnostic field, the precise role of brain biopsy is unknown. We aimed to study the clinical impact and safety of brain biopsies in unexplained CNS disorders.

METHODS

In this retrospective cohort study, we included all adult patients who were referred for a diagnostic work-up to our academic center with neuro-inflammatory, neuro-oncological, and neuro-infectious expertise and underwent a brain biopsy between January 2010 and December 2023. Typical cases of CNS neoplasms and infections were not analyzed. Brain biopsies were evaluated with respect to diagnostic and therapeutic impact and complication risk.

RESULTS

Brain biopsy was performed in 587 patients. Ninety-four patients with a CNS disorder of unknown cause, with 107 biopsies, were analyzed (44% female, median age 58 years). Postoperative diagnoses included brain tumors/lymphomas (37/94, 39%), inflammatory disorders (11/94, 12%), infections (8/94, 9%), autoimmune encephalitis (8/94, 9%), and primary angiitis of the CNS (4/94, 4%). Diagnostic yield of brain biopsy was 62%, increasing up to 72% after repeat biopsies, as 10 additional patients were diagnosed with a brain tumor. In 77% of patients, brain biopsy changed the treatment strategy. Symptomatic intracranial hemorrhage occurred in 4 of 107 brain biopsies (4%).

INTERPRETATION

In a selected population of patients with unexplained CNS disorders, clinical impact of brain biopsies is high, while being relatively safe. A multidisciplinary team approach is fundamental in establishing optimal indication for brain biopsy and subsequent treatment decisions.

Persistence and decay of neutralizing antibody responses elicited by SARS-CoV-2 infection and hybrid immunity in a Canadian cohort

A major challenge with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has been assessing the intensity, dynamics, and determinants of the antibody responses after infection and/or vaccination. Therefore, we aimed to characterize the longitudinal dynamics of the antibody responses among naturally infected individuals and individuals who achieved hybrid immunity in a large Canadian cohort. We demonstrate that anti-Spike IgGs and neutralizing antibody dynamics vary greatly among individuals with COVID-19, in peak antibody levels, rate of waning, and longevity of the antibody response. Additionally, we found an association between robust antibody responses and individuals with severe COVID-19 clinical symptoms during the first-month post-symptom onset. For individuals who achieved hybrid immunity, a robust increase in anti-S1 IgGs and neutralizing antibodies followed the first vaccination dose; however, there was a minimal increase in the anti-S1 IgGs and neutralizing antibody titers after administration of the second dose of the vaccine. Furthermore, neutralizing antibodies elicited by the wild-type virus alone were largely ineffective against emerging variants of concern in our natural infection-only cohort, in contrast to a much broader and more robust neutralization profile observed in individuals who achieved hybrid immunity. Our findings emphasize the need for global SARS-CoV-2 vaccination efforts to further sustain protective immune responses required to minimize viral spread and disease severity in the population. As SARS-CoV-2 variants continue to emerge, understanding the interplay between previous infections, vaccine durability, and virus evolution will be critical for guiding ongoing vaccination strategies.

IMPORTANCE

A major challenge with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has been assessing the intensity, dynamics, and determinants of the antibody response after infection and/or vaccination. Our paper addresses this in a large Canadian cohort with antibody responses that were generated by natural infection as well as vaccine in some persons studied.

From coughs to complications: the story of Chlamydia pneumoniae

Chlamydia pneumoniae is an obligate intracellular bacterium and a significant cause of respiratory infections. It is associated with upper and lower respiratory tract diseases, including bronchitis and pneumonia. The pathogen employs specific virulence factors, such as the Type III Secretion System (T3SS) and Inc proteins, to invade and subvert host cell machinery during its peculiar developmental life cycle. Chronic infections have been linked to asthma and, more controversially, to atherosclerosis and neurodegenerative diseases. Diagnosis primarily relies on PCR-based molecular assays, while treatment includes macrolides, tetracyclines or fluoroquinolones. Despite its clinical relevance, research on C. pneumoniae has declined in recent years, highlighting the need for renewed scientific focus.

Diagnostic performance of noninvasive tests for cytomegalovirus ileocolitis: a systematic review and meta-analysis

BACKGROUND/AIMS

Diagnosis of cytomegalovirus (CMV) ileocolitis traditionally requires colonoscopy with tissue biopsy. Due to potential complications in high-risk patients, there is growing interest in serum and stool tests for diagnosing this condition. We aimed to evaluate the diagnostic accuracy of these noninvasive tests compared to traditional gold standards.

METHODS

Two independent reviewers performed a comprehensive search on MEDLINE and Embase from inception up to October 1, 2023. Prospective and retrospective studies evaluating the performance of serum CMV polymerase chain reaction (PCR), serum CMV antigen (Ag), and stool CMV PCR in diagnosing CMV ileocolitis were included. Tissue histopathology or tissue CMV PCR served as reference standards. Diagnostic performances of each serum and stool test were calculated based on a meta-analysis using random-effects model.

RESULTS

A total of 30 studies, comprising 23 studies of serum CMV PCR, 9 of serum CMV Ag, and 7 of stool CMV PCR, were included. The pooled sensitivity, specificity, and area under summary receiver operating characteristic curves were 62% (95% confidence interval [CI], 51%-72%), 90% (95% CI, 79%-96%), and 0.81 for serum CMV PCR, 38% (95% CI, 26%-51%), 94% (95% CI, 70%-99%), and 0.56 for serum CMV Ag, and 53% (95% CI, 35%-70%), 91% (95% CI, 84%-95%), and 0.84 for stool CMV PCR.

CONCLUSIONS

Serum and stool tests cannot replace colonoscopy for diagnosing CMV ileocolitis due to their low sensitivities but may be useful when colonoscopy is not feasible. Positive results can aid diagnosis, given their high specificities. Serum and/or stool CMV PCR are preferred over CMV Ag.

Systemic Inflammatory Response Syndrome, Thromboinflammation, and Septic Shock in Fetuses and Neonates

This article explores systemic inflammatory response syndrome (SIRS), thromboinflammation, and septic shock in fetuses and neonates, offering a comprehensive examination of their pathophysiology, diagnostic criteria, and clinical implications. It identifies SIRS as an exaggerated response to external stress, disrupting the balance between inflammation and adaptive mechanisms, driven by cytokines such as TNF-α and IL-1. The fetal inflammatory response syndrome (FIRS), a subset of SIRS, is noted for its role in adverse neonatal outcomes, including organ damage, inflammation, and long-term developmental disorders. The article discusses the extensive effects of FIRS on critical systems, including the blood, lungs, central nervous system, and kidneys. It highlights the challenges in diagnosing and managing septic shock in neonates, focusing on the relationship between inflammation and the hemostatic system. Additionally, the paper points out recent advancements, such as the convergent model of coagulation and emerging biomarkers like microRNAs for early detection. Despite this progress, gaps remain in understanding the molecular mechanisms underlying these conditions and in developing effective therapeutic strategies. This highlights the necessity for targeted research to mitigate the morbidity and mortality associated with septic shock in neonates.

Identifying hotspots and risk factors for tick-borne encephalitis virus emergence at its range margins to guide interventions, Great Britain

BackgroundTick-borne encephalitis virus (TBEV) is expanding its range in Europe, with increasing human cases reported. Since the first detection of TBEV in ticks in the United Kingdom in 2019, one possible, two probable and two confirmed autochthonous cases in humans have been reported.AimWe aimed to understand the environmental and ecological factors limiting TBEV foci at their range edge and predict suitable areas for TBEV establishment across Great Britain (GB) by modelling patterns of exposure to TBEV in deer.MethodsWe developed spatial risk models for TBEV by integrating data between 2018 and 2021 on antibodies against tick-borne flavivirus in fallow, muntjac, red and roe deer with data on potential risk factors, including climate, land use, forest connectivity and distributions of bank voles and yellow-necked mice. We overlayed modelled suitability for TBEV exposure across GB with estimations on number of visitors to predict areas of high human exposure risk.ResultsModels for fallow, muntjac and roe deer performed well in independent validation (Boyce index > 0.92). Probable exposure to TBEV was more likely to occur in sites with a greater percentage cover of coniferous woodland, with multiple deer species, higher winter temperatures and rates of spring warming.ConclusionThe resulting TBEV suitability maps can be used by public health bodies in GB to tailor surveillance and identify probable high-risk areas for human exposure to guide awareness raising and vaccination policy. Combining animal surveillance and iterative spatial risk modelling can enhance preparedness in areas of tick-borne disease emergence.

Comparative evaluation of sanitation strategies against Listeria monocytogenes on food-contact surfaces in enoki mushroom (Flammulina velutipes) processing facilities

We investigated strategies to reduce Listeria monocytogenes contamination on food contact surfaces during enoki mushroom processing. Chemical disinfectants and thermal treatments were evaluated on conveyor belts, stainless steel, plastic surfaces, and Velcro strips. Without organic matter, chemical disinfectants effectively reduced L. monocytogenes, with stainless steel showing the highest susceptibility. Organic matter decreased disinfectant efficacy, but sodium hypochlorite remained most effective on stainless steel. Peracetic acid was more effective on conveyor belts and plastic surfaces than on stainless steel. Combining peracetic acid with dry heating synergistically reduced L. monocytogenes on Velcro strips. Moist heat at 70 °C alone was insufficient, but when combined with hot air drying, it effectively reduced L. monocytogenes on Velcro strips. Our findings emphasize the importance of surface-specific strategies combining chemical disinfection and thermal treatment for eliminating L. monocytogenes in mushroom processing environments.

Investigating the impact of mitochondrial DNA: Insights into blood transfusion reactions and mitigation strategies

BACKGROUND AND OBJECTIVES

Although transfusion reactions occur in less than 2% of recipients, they are currently one of the most serious concerns in blood transfusion. Damage-associated molecular patterns (DAMPs) are released from injured, stressed or dead cells, leading to inflammation and immune system activation. One of the recognized DAMPs is mitochondrial DNA (mtDNA). It is found in various blood products, including fresh frozen plasma (FFP), red blood cell units (RBCUs) and platelet concentrates (PCs), and can induce adverse reactions in recipients by stimulating the innate immune system and inflammatory cellular pathways. The aim of this study was to investigate the factors influencing the release of mtDNA in various blood products and its subsequent impact on transfusion reactions.

MATERIALS AND METHODS

In this study, mtDNA, mitochondrial DNA, mtDNA DAMPs, extracellular mtDNA, blood products, blood components and transfusion reactions between 2009 and 2023 were searched in Google Scholar, PubMed and Scopus databases.

RESULTS

This study has demonstrated the presence of mtDNA in the extracellular milieu of various blood products, including PCs, FFP and RBCUs. Understanding the determinants of mtDNA release and its implications for transfusion safety is critical. Strategies aimed at reducing mtDNA release, such as optimizing preparation techniques and donor selection criteria, hold promise for reducing transfusion-related complications.

CONCLUSION

By addressing these factors, healthcare providers can enhance the safety and efficacy of blood transfusion practices, ultimately improving patient outcomes.

In-Vitro Determination of Minimum Inhibitory Concentration (MIC) and Contact Time of Povidone-Iodine against Staphylococcus aureus and Klebsiella aerogenes Using Micro Suspension Test, Colorimetric Resazurin Microplate Assay, and Dey Engley Neutralizer Assay

Background and Objective

The human nasal passages host major human pathogens. Recent research suggests that the microbial communities inhabiting the epithelial surfaces of the nasal passages play a key factor in maintaining a healthy microenvironment by affecting both resistance to pathogens and immunological responses. Colonization of the nasal cavity by different pathogens such as Staphylococcus aureus and Klebsiella aerogenes, is associated with a higher postoperative infection morbidity. Povidone-iodine (PVP-I) as an antiseptic has been proven to display high antibacterial, antiviral, and antifungal properties even at low concentrations, and was shown to be effective in the control of infections to limit their impact and spread. It can be used as a topical antiseptic for skin decontamination and wound management, as a nasal spray, or as a gargle. There are different methods in testing the efficacy of potential antimicrobial suspensions. This study aimed to determine the concentration of PVP-I that is most effective in nasal decolonization using microsuspension test and colorimetric minimum inhibitory concentration (MIC) determination assays, resazurin microtiter assay (REMA), and Dey-Engley (D/E) neutralizer assay. The findings of this study will contribute to knowledge regarding the intended use of PVP-I in microbial control, particularly in bacterial infections.

Methods

Several dilutions (2.0%, 1.0%, 0.5%, 0.25%, 0.1% and 0.09%) of commercially bought 10% (10 mg per 100 ml) povidone-iodine were prepared and tested against a standardized inoculum (1x105) of Staphylococcus aureus and Klebsiella aerogenes at different contact times (5 seconds, 10 seconds, 30 seconds, 1 minute, and 5 minutes). Microdilution suspension test was performed to determine the log reduction per variable, while REMA and D/E neutralizer assay were used to determine the MIC. A value of greater than or equal to 5 log reduction was considered effective for microdilution suspension test. Estimates of agreement statistics were used to interpret the results of the assay in which the overall percent agreement (OPA), positive percent agreement (PPA), negative percent agreement (NPA), and Cohen's kappa statistics were calculated.

Results

Povidone-iodine concentration of 0.25% exhibited ≥5 log reduction against K. aerogenes at the minimum contact time of 5 seconds. On the other hand, a slightly higher PVP-I concentration was required to achieve ≥5 log reduction for S. aureus at 0.5% concentration and a minimum contact time of 1 minute. There was an observed concordance of the results of REMA and D/E neutralizer as MIC colorimetric indicators, which yielded an overall test percent agreement of 90.30% (95% CI: 84.73-94.36), and a strong level of agreement (Κ = 0.8, p<0.0001). A lower overall percent agreement for both REMA and D/E neutralizer versus the microsuspension test was observed at 79.17% (Κ = 0.57, p<0.0001) and 78.18% (Κ = 0.55, p<0.0001), respectively.

Conclusion

Low povidone-iodine concentrations (i.e., 0.5% against S. aureus and 0.25% against K. aerogenes) were observed to have bactericidal activity of at least 5 log reduction as rapid as the minimum contact time of 5 seconds. Furthermore, D/E and REMA, as colorimetric indicators, had comparable performance (OPA = 90.30%; Κ = 0.8, p<0.0001) suggesting that both REMA and D/E neutralizer assay may detect the same range of minimum inhibitory concentration for the organisms and disinfectant tested in this study.

Storage Temperature Affects Platelet Activation and Degranulation in Response to Stimuli

The refrigeration (cold storage) of platelet components provides several benefits over room-temperature (RT) storage, extending the shelf-life up to 21 days. However, the effect of storage conditions on platelet activation in response to stimulation remains unclear. A paired study was conducted where buffy-coat platelet concentrates were pooled, split, and allocated to RT or cold storage (n = 6 in each group). Platelet samples were taken on days 1, 7, 14, and 21, which were tested without stimulation or following activation with TRAP-6, A23187, lipopolysaccharides, or Histone-H4. Imaging flow cytometry was used to assess the surface characteristics of platelets and extracellular vesicles (EVs). The supernatant concentration of EGF, RANTES, PF4, CD62P, IL-27, CD40L, TNF-α, and OX40L was examined using ELISA. Cold-stored platelets generated a greater proportion of procoagulant platelets and EVs than RT-stored platelets in response to stimulation. The supernatant of cold-stored components contained lower concentrations of soluble factors under basal conditions, suggesting that platelet granules were better retained. Cold-stored platelets released higher concentrations of soluble factors following stimulation with TRAP-6, A23187, or Histone-H4. Only cold-stored platelets responded to lipopolysaccharides. These data demonstrate that cold-stored platelets retain the capacity to respond to stimuli after 21 days of storage, which may facilitate improved functional post-transfusion.

Novel Techniques to Unravel Causative Bacterial Ecological Shifts in Chronic Urinary Tract Infection

Chronic urinary tract infection (UTI) presents with protracted lower urinary tract symptoms and elevated urinary leukocyte counts, but its bacterial etiological agents remain obscure. In this cross-sectional investigation, we aimed to unravel the role of the bladder microbiota in chronic UTI pathogenesis by studying the host immune response. Urine samples were collected from healthy controls (HT), chronic UTI patients who had not initiated treatment (PT) and those undergoing treatment (OT), then sorted into white blood cell (WBC) and epithelial cell (EPC) fractions. Bacteria associated with both fractions were identified by chromogenic agar culture coupled with mass spectrometry and 16S rRNA sequencing. Distinct WBC-exclusive bacteria were observed in the healthy population, but this pattern was less obvious in patients, plausibly due to epithelial shedding and breaching of the urothelial barrier. We also described a bacterial fingerprint guided by Escherichia that was able to stratify patients based on symptom severity. Clustering analyses of mean rank changes revealed highly statistically significant upward and downward ecological shifts in communities of bacteria between the healthy and diseased populations. Interestingly, many of the most abundant genera identified in sequencing remained stable when compared between the study cohorts. We concluded that reshuffling of the urinary microbiome, rather than the activity of a single known urinary pathogen, could drive chronic UTI.

T and B cell responses in different immunization scenarios for COVID-19: a narrative review

Vaccines against COVID-19 have high efficacy and low rates of adverse events. However, none of the available vaccines provide sterilizing immunity, and reinfections remain possible. This review aims to summarize the immunological responses elicited by different immunization strategies, examining the roles of homologous and heterologous vaccination and hybrid immunity. Homologous vaccination regimens exhibit considerable variation in immune responses depending on the vaccine platform, particularly concerning antibody titers, B cell activation, and T cell responses. mRNA vaccines, such as mRNA-1273 and BNT162b2, consistently generate higher and more durable levels of neutralizing antibodies and memory B cells compared to adenovirus-based vaccines like Ad26.COV2.S and ChAdOx1. The combination of two distinct vaccine platforms, each targeting different immune pathways, seems to be more effective in promoting long-lasting B cell responses and potent T cell responses. The high heterogeneity of the available studies, the different dosing schemes, the succession of new variants, and the subjects' immunological background do not allow for a definitive conclusion. Overall, heterologous vaccination strategies, combining sequentially viral vector and mRNA may deliver a more balanced and robust humoral and cellular immune response compared to homologous regimens. Hybrid immunity, which arises from SARS-CoV-2 infection preceded or followed by vaccination produces markedly stronger immune responses than either vaccination or infection alone. The immune response to SARS-CoV-2 variants of concern varies depending on both the vaccine platform and prior infection status. Hybrid immunity leads to a broader antibody repertoire, providing enhanced neutralization of variants of concern. Heterologous vaccination and hybrid immunity may provide further opportunities to enhance immune responses, offering broader protection and greater durability of immunity. However, from all-cause mortality, symptomatic or severe COVID, and serious adverse events at present it is not possible to infer different effects between homologous and heterologous schemes. Next-generation vaccines could involve tweaks to these designs or changes to delivery mechanisms that might improve performance.

Periodontal Status and Herpesiviridae, Bacteria, and Fungi in Gingivitis and Periodontitis of Systemically Compromised Pediatric Subjects: A Systematic Review

BACKGROUND

Gingivitis and periodontitis are microbially associated diseases, with some features characteristic of pediatric age and others linked to systemic diseases. While the role of periodontal pathogenic bacteria is well recognized, the contribution of fungi and viruses, particularly Herpesviridae, remains controversial. Studies in adults have highlighted the presence of Herpesviridae, but evidence in pediatric subjects, especially systemically compromised, is limited. This systematic review aimed to assess periodontal status (e.g., health, gingivitis, periodontitis, necrotizing gingivitis, and/or periodontitis) and the subgingival and/or salivary microbial (bacterial, viral, and fungal) profile in systemically compromised pediatric (≤18 years) subjects with gingivitis and/or periodontitis compared to clinical periodontal health.

METHODS

The review protocol was registered on PROSPERO (CRD42024597695) and followed the PRISMA statement. Data from eight studies were descriptively analyzed and qualitatively assessed through ROBINS-I and JBI tools.

RESULTS

CMV was frequently detected, particularly in necrotizing gingivitis (19.40%). EBV was found in necrotizing gingivitis (20.69%) and periodontitis (10.34%); HSV was mainly associated with gingivitis and necrotizing gingivitis. Bacteria species in periodontitis included Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium, and Campylobacter species. Candida albicans was detected in periodontitis, suggesting a fungal involvement in the disease's pathogenesis. Although the bacterial and fungal profile was not investigated, limited viral presence was noted in subjects with healthy periodontium, indicating a stable microbiome.

CONCLUSIONS

These findings underscore the dynamics of microbial interactions in the progression of periodontal disease in systemically compromised pediatric subjects.

Assessing the distribution and human health risks of cationic surface-active agents in honey from China

Cationic surface-active agents (CSAAs) can persist in ambient water, be ingested by bees, and contaminate honey. Residues of CSAAs in honey remains unknown. This study measured the residual levels of five CSAAs in 271 honey samples from China using ultrahigh-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry. Residual benzalkonium chloride-C12 (BAC-C12), BAC-C14, BAC-C16, chlorhexidine (CHG), and 4-chloraniline levels were 0.0098-2.1468, 0.0061-1.7492, 0.0012-1.6305, 0.1576-0.8401, and 0.0019-0.0234 μg kg-1, respectively. CHG and all BAC were detected in 100 % of Z. jujuba, V. negundo var. heterophylla, wildflower, L. chinensis, and D. longan Lour honey; T. tuan honey had the lowest detection rate of any CSAAs. BAC-C16 had the highest residual level among all BAC tested in Central, North China. CHG levels were detected in 91.38 % of samples in North China and 100 % in East China. BAC-C12 was significantly higher in A. cerana versus A. mellifera honey (P < 0.001). Hazard quotient and Hazard index values indicate that CSAAs residuals in honey do not pose a health risk. Correlation analysis revealed a positive correlation between BACs resides in honey and surrounding environment. The findings suggest that continuous monitoring of CSAAs in honey is imperative to ensure its safety for human consumption, while also serving as an effective matrix to assess the environmental pollution of a given region.

Tackling cutaneous herpes simplex virus disease with topical immunomodulators-a call to action

SUMMARYAntivirals play important roles in restricting viral diseases. Nevertheless, they act on a relatively limited number of viruses and occasionally display partial effectiveness in some tissues or against escape variants. Although vaccination remains the most cost-effective approach for preventing microbial diseases, developing prophylactic or therapeutic solutions for pathogens, such as herpes simplex viruses (HSVs), that effectively reduce their clinical manifestations in the skin has proven exceptionally challenging despite extensive research. Alternatively, a less explored approach for tackling HSV skin infection involves using topical immunomodulatory molecules to potentiate the host's innate antiviral immune responses. When applied directly to herpetic skin lesions where viral antigen is present, this strategy has the potential to elicit virus-specific adaptive immunity. Based on currently available data, we foresee substantial potential for this approach in addressing HSV skin infections, along with additional prospects to advance understanding of skin biology and apply relevant new findings to other dermatological conditions. However, due to the limited number of case studies evaluating this method and its safety profile, particularly in immunocompromised individuals and pregnant women, further research is crucial, especially to assess the effects of immunomodulators in these vulnerable populations. Here, we revisit and discuss the use of immunomodulatory molecules for potentiating the host immune response against HSV skin infection and call for action for increased research and clinical trials regarding the possible benefits of this latter strategy for treating HSV cutaneous disease and recurrences. We also revisit and discuss antivirals and vaccine candidates against HSVs.

Germline variants and mosaic chromosomal alterations affect COVID-19 vaccine immunogenicity

Vaccine immunogenicity is influenced by the vaccinee's genetic background. Here, we perform a genome-wide association study of vaccine-induced SARS-CoV-2-specific immunoglobulin G (IgG) antibody titers and T cell immune responses in 1,559 mRNA-1273 and 537 BNT162b2 vaccinees of Japanese ancestry. SARS-CoV-2-specific antibody titers are associated with the immunoglobulin heavy chain (IGH) and major histocompatibility complex (MHC) locus, and T cell responses are associated with MHC. The lead variants at IGH contain a population-specific missense variant (rs1043109-C; p.Leu192Val) in the immunoglobulin heavy constant gamma 1 gene (IGHG1), with a strong decreasing effect (β = -0.54). Antibody-titer-associated variants modulate circulating immune regulatory proteins (e.g., LILRB4 and FCRL6). Age-related hematopoietic expanded mosaic chromosomal alterations (mCAs) affecting MHC and IGH also impair antibody production. MHC-/IGH-affecting mCAs confer infectious and immune disease risk, including sepsis and Graves' disease. Impacts of expanded mosaic loss of chromosomes X/Y on these phenotypes were examined. Altogether, both germline and somatic mutations contribute to adaptive immunity functions.

Comprehensive integration of diagnostic biomarker analysis and immune cell infiltration features in sepsis via machine learning and bioinformatics techniques

Introduction

Sepsis, a critical medical condition resulting from an irregular immune response to infection, leads to life-threatening organ dysfunction. Despite medical advancements, the critical need for research into dependable diagnostic markers and precise therapeutic targets.

Methods

We screened out five gene expression datasets (GSE69063, GSE236713, GSE28750, GSE65682 and GSE137340) from the Gene Expression Omnibus. First, we merged the first two datasets. We then identified differentially expressed genes (DEGs), which were subjected to KEGG and GO enrichment analyses. Following this, we integrated the DEGs with the genes from key modules as determined by Weighted Gene Co-expression Network Analysis (WGCNA), identifying 262 overlapping genes. 12 core genes were subsequently selected using three machine-learning algorithms: random forest (RF), Least Absolute Shrinkage and Selection Operator (LASSO), and Support Vector Machine-Recursive Feature Elimination (SVW-RFE). The utilization of the receiver operating characteristic curve in conjunction with the nomogram model served to authenticate the discriminatory strength and efficacy of the key genes. CIBERSORT was utilized to evaluate the inflammatory and immunological condition of sepsis. Astragalus, Salvia, and Safflower are the primary elements of Xuebijing, commonly used in the clinical treatment of sepsis. Using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), we identified the chemical constituents of these three herbs and their target genes.

Results

We found that CD40LG is not only one of the 12 core genes we identified, but also a common target of the active components quercetin, luteolin, and apigenin in these herbs. We extracted the common chemical structure of these active ingredients -flavonoids. Through docking analysis, we further validated the interaction between flavonoids and CD40LG. Lastly, blood samples were collected from healthy individuals and sepsis patients, with and without the administration of Xuebijing, for the extraction of peripheral blood mononuclear cells (PBMCs). By qPCR and WB analysis. We observed significant differences in the expression of CD40LG across the three groups. In this study, we pinpointed candidate hub genes for sepsis and constructed a nomogram for its diagnosis.

Discussion

This research not only provides potential diagnostic evidence for peripheral blood diagnosis of sepsis but also offers insights into the pathogenesis and disease progression of sepsis.

Maternal-Fetal Listeriosis in China: Clinical and Genomic Characteristics From an ST8 Listeria monocytogenes Case

Background

Listeriosis, a severe foodborne infection caused by Listeria monocytogenes, poses significant risks during pregnancy, including maternal-neonatal transmission. This study describes the clinical and genomic characteristics of an sequence type 8 (ST8) L. monocytogenes strain involved in maternal-neonatal transmission during pregnancy.

Methods

Clinical presentation, diagnostic process, and treatment outcomes of the case were documented in detail. Whole-genome sequencing (WGS) and subsequent genomic analyses were performed on L. monocytogenes isolates obtained from the maternal and neonatal blood cultures.

Results

A 33-week pregnant woman presented with decreased fetal movements and underwent an emergency cesarean delivery. Postpartum, she developed a high fever, and blood cultures from both the mother and the neonate the day after caesarean delivery confirmed L. monocytogenes infection. WGS revealed that the isolates belonged to serotype 1/2a, ST8, clonal complex (CC) 8, and lineage II. Both isolates exhibited susceptibility to first-line antibiotics, including penicillin and ampicillin, and contained virulence and stress adaptation genes such as LIPI-1 and SSI-1. Phylogenetic analysis based on cg-SNP linked the clinical isolates to foodborne ST8 strains from Huzhou and Shanghai, suggesting potential contamination routes.

Conclusion

This case highlights the importance of timely diagnosis and effective antibiotic management in preventing adverse pregnancy outcomes. It also underscores the need for enhanced food safety surveillance and genomic monitoring of L. monocytogenes to better understand the transmission dynamics and to avoid the extension of a foodborne infection.