Burden of infectious diseases and bacterial antimicrobial resistance in China: a systematic analysis for the global burden of disease study 2019

The impact of an innovative payment model on the direct economic burden of infectious disease inpatients: evidence from a pilot City in central China

BACKGROUND

Timely treatment of infectious diseases is essential to prevent transmission and protect public health. However, the substantial direct economic burden often impedes infectious disease patients from accessing timely treatment. Currently, China has implemented an innovative payment model called Diagnosis-Intervention Packet (DIP) in 71 pilot cities. This study aims to evaluate the impact of DIP on the direct economic burden of infectious disease inpatients.

MATERIALS AND METHODS

The dataset comprises 724,489 inpatient reimbursement records from City A spanning from January 2019 to June 2023. We conducted an interrupted time series analysis (ITSA) on six outcomes for a total of 2384 inpatients, with the top six being high-incidence Category B infectious diseases in City A. Further robustness analyses focusing on inpatients covered by Rural Residents Basic Medical Insurance (URRBMI), as well as those hospitalized for HBV and TB, were conducted to support our findings.

RESULTS

Following the implementation of DIP, we observed downward trends in average inpatient expenditure (β3 = -237.96, P < 0.01), average drug expenditure (β3 = -164.21, P < 0.01), average inpatient out-of-pocket expenditures (OOPs) (β3 = -124.58, P < 0.05), and the proportion of OOPs (β3 = -0.31, P < 0.01). These correspond to monthly decreasing slopes of ¥237.96, ¥164.21, ¥124.58, and 0.31%, respectively. When analyzing the proportion of OOPs by catalog status, a significant decline was observed only for non-catalog items, with a decreasing slope of 0.19% (β3 = -0.19, P < 0.01). The reintroduction of ITSA focusing on URRBMI inpatients, as well as HBV and TB inpatients, demonstrated the robustness of the results.

CONCLUSION

The DIP appears to contribute to reducing the direct economic burden for patients with infectious diseases. On the one hand, DIP seems to facilitate a reduction in inpatient medical expenditures, particularly by containing drug expenditures, which constitute a major component of spending for infectious disease patients. On the other hand, the decline in the proportion of OOPs is primarily concentrated in out-of-catalog items, suggesting that the DIP model may help limit doctors' tendencies to shift costs onto patients.

Enhancing 1O2 Production with Biomimetic Pt Catalysts through Electronic Structure Modification

Singlet oxygen (1O2) is an excellent reactive oxygen species in the biomedical disinfection field; however, efficient and selective generation of 1O2 remains challenging. Herein, we design bioinspired Pt@UiO-66-X catalysts (X = -NH2, -H, -Br), with Pt nanoparticles as active centers and metal-organic framework (MOF) nanocavities as biomimetic binding pockets, to form a tailored electronic microenvironment for enhancing 1O2 generation. The results demonstrate that the electron-withdrawing functionalized Pt@UiO-66-Br can significantly improve the production efficiency of 1O2, which is 1.5 and 2.5 times higher than those of Pt@UiO-66 and Pt@UiO-66-NH2, respectively. Ab initio calculations reveal that electron-withdrawing functional groups can reduce the local electron density of Pt, thereby leading to a decrease in antibonding-orbital occupancy in Pt-Oads and subsequently facilitating the formation of *OO. Importantly, the Pt@UiO-66-Br catalyst shows good antibacterial properties both in vitro and in vivo. This work provides a promising prospect for the rational design of high-performance biomimetic catalysts for antibacterial application.

Discovery of 3-hydroxypyridin-4(1H)-ones ester of ciprofloxacin as prodrug to combat biofilm-associated Pseudomonas aeruginosa

Chronic infections by Pseudomonas aeruginosa (P. aeruginosa) are frequently complicated due to its ability to form biofilm, which also effectively enhance its resistance to antibiotics. Bacteria-specific antibiotic delivery could locally increase drug concentration to break antimicrobial resistance and reduce the drug's peripheral side effects. The standard-of-care drug ciprofloxacin suffers from severe systemic side effects and was therefore chosen for this approach. It has been identified that 3-hydroxypyridin-4(1H)-one as siderophore mimics could be utilized by P. aeruginosa, and reduced bacterial biofilm formation. In this work, ciprofloxacin was conjugated to 3-hydroxypyridin-4(1H)-one by cleavable linkers to yield prodrugs, which were strategically designed and synthesized to function as dual antibacterial and antibiofilm agents against P. aeruginosa. Conjugate 5c was identified and has the best minimum inhibitory concentrations of 1.07 μM against P. aeruginosa PAO1, and reduced 61.7 % of biofilm formation. In addition, 5c destroyed 75.7 % of mature biofilms. Further studies on the uptake mechanisms showed that the bacterial siderophore-dependent iron transport system was involved in the uptake of the conjugates. Conjugate 5c interfered with iron uptake by bacteria, inhibited their motilities and reduced the production of virulence. Furthermore, prodrug 5c reduced toxicity in vivo and in vitro and showed a positive therapeutic effect in the treatment of Caenorhabditis elegans (C. elegans) infected by P. aeruginosa. These results demonstrate that 3-hydroxypyridin-4(1H)-ones-ciprofloxacin prodrugs are potent in the treatment of biofilm-associated drug-resistant P. aeruginosa infections.

A Review on Rare and Symbiotic Actinobacteria: Emerging Biotechnological Tools Against Antimicrobial Resistance

Antimicrobial resistance (AMR) poses a global threat to public health, with projections estimating 10 million deaths annually by 2050 if current trends persist. Actinobacteria, renowned for their biosynthetic capacity, are a key source of bioactive compounds, producing over 75% of known antibiotics. The adaptability of these microorganisms allows them to thrive in diverse habitats, including extreme ones, through the production of secondary metabolites that are of paramount importance for industry. Furthermore, actinobacteria are capable of living in symbiosis with several organisms, producing metabolites to protect and promote the growth of the host in exchange for nutrients and shelter. Some of these metabolites, such as antibiotics, play a key role in combating host pathogens and can be biotechnologically exploited to combat human resistant pathogens. This review presents the origins of AMR, the unique biology of actinobacteria, as well as their diverse biosynthetic pathways and their role in mitigating the AMR crisis. It also highlights the need for innovative biotechnological strategies for the isolation of rare and understudied actinobacteria, as symbiotic actinobacteria, to avoid rediscovery of molecules while finding new potential natural products and scaffolds for synthetic drugs. By providing a better understanding of their ecological, genomic, and metabolic diversity, this review provides valuable insights into the exploration of rare and symbiotic actinobacteria for developing antimicrobial solutions.

Infectious disease-specific health literacy and its influencing factors: Research results based on a cross-sectional design study carried out in Shandong Province's rural areas

Rural residents face a higher risk of infectious diseases, and infectious disease-specific health literacy (IDSHL) is a crucial means of managing these risks. This study intended to survey the levels of IDSHL among rural residents in Shandong Province, China, and explore the influencing factors of IDSHL. In 2022, a cross-sectional design investigation was carried out in Shandong Province of China, involving 2283 participants recruited through a multistage sampling approach in rural regions. A cognitive questionnaire was used to assess participants' levels of IDSHL. Pearson χ2 test was performed to compare the differences in the distribution of categorical variables between the adequate and inadequate IDSHL groups. Multicollinearity diagnosis analysis was utilized to evaluate multicollinearity. Multiple logistic regression was used to detect the possible influencing factors of IDSHL. Among the participants, 31.80% had adequate IDSHL. Multiple logistic regression demonstrated that education (odds ratio (OR)junior high school = .71, 95% confidence interval (CI) of OR: 0.51-0.99, P = .04; ORuniversity or above = 2.62, 95% CI of OR: 1.67-4.11, P < .01), occupation (ORbusiness = 2.19, 95% CI of OR: 1.34-3.57, P < .01; ORothers = 1.46, 95% CI of OR: 1.02-2.10, P = .04), family income (OR1-3 10,000 RMB = 2.83, 95% CI of OR: 1.98-4.05, P < .01; OR3-6 10,000 RMB = 1.75, 95% CI of OR: 1.21-2.53, P < .01), "whether the participant used a smartphone in daily life" (OR = 2.02, 95% CI of OR: 1.32-3.09, P < .01) and "whether knowledge of infectious disease prevention and control could be acquired" (OR = 11.77, 95% CI of OR: 6.44-21.54, P < .01) were associated with adequate IDSHL. The rural residents' level of adequate IDSHL in China's Shandong Province, was unsatisfactory. Special health education is needed to be implemented to enhance rural residents' IDSHL and should target key populations with low levels of IDSHL.

Iron oleate containing lipid nanoparticles prepared by gradient solvent diffusion method for oxidative stress dependent antibacterial therapy

This study was designed to assess the efficacy of iron oleate lipid nanoparticles (IO-LNPs) in inducing Fenton reaction as a therapeutic approach for bacterial infections caused by Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), both of which are common pathogens in skin wound infections. IO-LNPs were synthesized using the gradient solvent diffusion method, followed by characterization of their particle size, polydispersity index (PDI), zeta potential, and morphology. In vitro antibacterial assays were conducted to evaluate the inhibitory effects of IO-LNPs on bacterial growth; the impact on bacterial viability was confirmed via live/dead staining assays. Furthermore, the mechanism underlying the antibacterial activity of IO-LNPs was investigated. Lastly, in vivo antibacterial studies were performed in a mouse model infected with S. aureus to evaluate the efficacy of IO-LNPs. The results indicated that the IO-LNPs synthesized via the gradient solvent diffusion method possessed a particle size of 114 ± 2 nm, a PDI of 0.198, and a zeta potential of -12.3 ± 1.73 mV. The IO-LNPs demonstrated a significant reduction in the viability of S. aureus and E. coli, effectively inhibiting the formation of biofilms by these bacteria and disrupting pre-existing biofilms. Crucially, in the skin infection model, IO-LNPs significantly inhibited the growth of S. aureus and accelerated wound healing. By day 13, the wound area in the 90 % minimum inhibitory concentration (MIC90) group had decreased to 6.53 %. Collectively, these findings suggest that IO-LNPs, as a novel antibacterial agent, can effectively inhibit bacterial growth and disrupt biofilms by inducing Fenton reaction, thereby demonstrating considerable potential against antibiotic-resistant bacterial infections. This study establishes a theoretical foundation for the development of new treatment modalities for skin wound infections.

Phage engineering to overcome bacterial Tmn immunity in Dhillonvirus

Bacteria possess numerous defense systems against phage infections, which limit phage infectivity and pose challenges for phage therapy. This study aimed to engineer phages capable of evading these defense systems, using the Tmn defense system as a model. We identified an anti-Tmn protein in the ΦSMS22 phage from the Dhillonvirus genus that inhibits Tmn function in Escherichia coli. Introducing this gene into the Tmn-sensitive ΦKSS9 phage enabled it to evade Tmn immunity. Additionally, we found that a single mutation in the nmad5 gene, a DNA modification enzyme in Dhillonvirus, prevented Tmn from sensing phage infection. By mutating the nmad5 gene in the Tmn-sensitive Dhillonvirus, we demonstrated that engineering phages to evade bacterial sensing mechanisms is another viable strategy. These two phage engineering approaches-introducing anti-defense genes and mutating sensing-related genes-present a promising strategy for establishing effective phage therapy by neutralizing bacterial defense systems.

Clinical evaluation of a multiplex droplet digital PCR for diagnosing suspected bloodstream infections: a prospective study

Background

Though droplet digital PCR (ddPCR) has emerged as a promising tool for early pathogen detection in bloodstream infections (BSIs), more studies are needed to support its clinical application widely due to different ddPCR platforms with discrepant diagnostic performance. Additionally, there is still a lack of clinical data to reveal the association between pathogen loads detected by ddPCR and corresponding BSIs.

Methods

In this prospective study, 173 patients with suspected BSIs were enrolled. A multiplex ddPCR assay was used to detect 18 pathogens. The results of ddPCR testing were evaluated in comparison with blood cultures (BCs) and clinical diagnosis. Taking BC as the gold standard, receiver operating characteristic curve and Cohen's kappa agreement were used to investigate whether the pathogen load could predict a corresponding culture-proven BSI for the top five microorganisms detected by ddPCR.

Results

Of the 173 blood samples collected, BC and ddPCR were positive in 48 (27.7%) and 92 (53.2%) cases, respectively. Compared to BC, the aggregate sensitivity and specificity for ddPCR were 81.3% and 63.2%, respectively. After clinical adjudication, the sensitivity and specificity of ddPCR increased to 88.8% and 86.0%, respectively. There were 143 microorganisms detected by ddPCR. The DNA loads of these microorganisms ranged from 30.0 to 3.2×105 copies/mL (median level: 158.0 copies/mL), 72.7% (104/143) of which were below 1,000 copies/mL. Further, statistical analysis showed the DNA loads of Escherichia coli (AUC: 0.954, 95% CI: 0.898-1.000, κ=0.731, cut-off values: 93.0 copies/mL) and Klebsiella pneumoniae (AUC: 0.994, 95% CI: 0.986-1.000, κ=0.834, cut-off values: 196.5 copies/mL) were excellent predictors for the corresponding BSIs. The DNA loads of Pseudomonas aeruginosa (AUC: 0.816, 95% CI: 0.560-1.000, κ=0.167), Acinetobacter baumannii (AUC: 0.728, 95% CI: 0.195-1.000), and Enterococcus spp. (AUC: 0.282, 95% CI: 0.000-0.778) had little predictive value for the corresponding culture-proven BSIs.

Conclusion

Our results indicate that the multiplex ddPCR is a promising platform as a complementary add-on to conventional BC. The DNA loads of E. coli and K. pneumoniae present excellent predictive value for the corresponding BSIs. Further research is needed to explore the predictive potential of ddPCR for other microorganisms.

[Disease burden of communicable diseases among children and adolescents aged under 20 years in China from 1990 to 2021]

OBJECTIVES

To investigate the epidemiological characteristics and changing trends of communicable diseases among children and adolescents in China from 1990 to 2021.

METHODS

Based on the Global Burden of Disease Database, epidemiological indicators for communicable diseases among the population aged under 20 years in China from 1990 to 2021 were selected to analyze the burden of communicable diseases in this population, and a comparative analysis was performed with global data as well as data from Western Europe and North America.

RESULTS

In 1990-2021, the overall burden of communicable diseases tended to decrease among children and adolescents in China. In 2021, the prevalence rate of communicable diseases in China was lower than the global prevalence rate and was higher than that in Western Europe and North America. There was a significant reduction in the mortality rate of communicable diseases, and the gap with Western Europe and North America gradually narrowed year by year. The overall incidence rate, mortality rate, and disability-adjusted life year rate of communicable diseases in males were higher than those in females, and respiratory infections and intestinal infections were more common in children aged <5 years, while the incidence rate of sexually transmitted diseases was higher in adolescents.

CONCLUSIONS

From 1990 to 2021, the disease burden of communicable diseases among the population under 20 years old in China has significantly decreased. However, there is still a certain gap compared to developed regions. Strengthening the prevention and control of diseases such as respiratory infections and acquired immunodeficiency syndrome, as well as enhancing health interventions for children under 5 years old, will help improve the overall health level of children and adolescents in China.

Design, Synthesis, Antibacterial, and Antifungal Evaluation of a New Series of Quinazoline - Thiazole and/or Quinazoline - Triazole Hybrids as Bioactive Heterocycles

Herein, a one-pot reaction between cyclohexanone, thiourea, and 2,5-dimethoxybenzaldehyde allowed to prepare hexahydroquinazoline-2(1H)-thione4 firstly, which followed by reacting with hydrazine hydrate to produce the corresponding 2-hydrazinylhexahydroquinazoline 6. Interesting analogs of thiazolo[3,2-a]quinazoline 713 where obtained when hexahydroquinazoline-2(1H)-thione 4 reacted with 1,2-dibromoethane, chloroacetyl chloride, bromoacetic acid, bromoacetic acid/4-chlorobenzaldehyde, 2-bromopropionic acid, ethyl bromo cyanoacetate, and/or bromomalononitrile; respectively. While triazolo[4,3-a] quinazoline 14-16 were created when 2-hydrazinylhexahydroquinazoline 6 reacted with triethyl orthoformate, acetic anhydride, and carbon disulfide respectively. Numerous spectroscopy tests, including FT-IR, NMR (1H &13 C), and MS spectrum, proved all the newly produced analogs. Additionally, the new analogs were examined for their antibacterial and antifungal properties against Escherichia coli, Staphylococcus aureus, and Candida albicans. It was discovered that triazolo[4,3-a] quinazoline analogs 14-16 have superior bacterial and fungal activity when compared to the corresponding conventional doses of Streptomycin andGriseofulvin. Towards Candida albicans; compounds 14, 15, and 16 increase activity with 1.14 %, 1.15 %, and 1.21 %, respectively more than griseofulvin.While, for Staphylococcus aureus; compounds 14, 15, and 16 increase activity with 1.5 %, 1.5 %, and 1.7 %, respectively more than streptomycin. Morever, for Escherichia coli; compounds 14, 15, and 16 increase activity with 1.19 %, 1.21 %, and 1.22 %, respectively more than streptomycin. Finally, structure activity relationships show that quinazoline derivatives exhibit higher activity when fused to pyrazole ring 14-16 as compared when fused thiophene ring 7-13.

Transmission and control strategies of antimicrobial resistance from the environment to the clinic: A holistic review

The environment serves as a significant reservoir of antimicrobial resistance (AMR) microbes and genes and is increasingly recognized as key source of clinical AMR. Modern human activities impose an additional burden on environmental AMR, promoting its transmission to clinical setting and posing a serious threat to human health and welfare. Therefore, a comprehensive review of AMR transmission from the environment to the clinic, along with proposed effective control strategies, is crucial. This review systematically summarized current research on the transmission of environmental AMR to clinical settings. Furthermore, the transmission pathways, horizontal gene transfer (HGT) mechanisms, as well as the influential drivers including triple planetary crisis that may facilitate AMR transfer from environmental species to clinical pathogens are highlighted. In response to the growing trend of AMR transmission, we propose insightful mitigation strategies under the One Health framework, integrating advanced surveillance and tracking technologies, interdisciplinary knowledge, multisectoral interventions, alongside multiple antimicrobial use and stewardship approaches to tacking development and spread of AMR.

Mixed-charge hyperbranched polymer nanoparticles with selective antibacterial action for fighting antimicrobial resistance

The escalating menace of antimicrobial resistance (AMR) presents a profound global threat to life and assets. However, the incapacity of metal ions/reactive oxygen species (ROS) or the indiscriminate intrinsic interaction of cationic groups to distinguish between bacteria and mammalian cells undermines the essential selectivity required in these nanomaterials for an ideal antimicrobial agent. Hence, we devised and synthesized a range of biocompatible mixed-charge hyperbranched polymer nanoparticles (MCHPNs) incorporating cationic, anionic, and neutral alkyl groups to effectively combat multidrug-resistant bacteria and mitigate AMR. This outcome stemmed from the structural, antibacterial activity, and biocompatibility analysis of seven MCHPNs, among which MCHPN7, with a ratio of cationic groups, anionic groups, and long alkyl chains at 27:59:14, emerged as the lead candidate. Importantly, owing to inherent differences in membrane potential among diverse species, alongside its nano-size (6-15 nm) and high hydrophilicity (Kow = 0.04), MCHPN7 exhibited exceptional selective bactericidal effects over mammalian cells (selectivity index > 564) in vitro and in vivo. By inducing physical membrane disruption, MCHPN7 effectively eradicated antibiotic-resistant bacteria and significantly delayed the emergence of bacterial resistance. Utilized as a coating, MCHPN7 endowed initially inert surfaces with the ability to impede biofilm formation and mitigate infection-related immune responses in mouse models. This research heralds the advent of biocompatible polymer nanoparticles and harbors significant implications in our ongoing combat against AMR. STATEMENT OF SIGNIFICANCE: The escalating prevalence of antimicrobial resistance (AMR) has been acknowledged as one of the most significant threats to global health. Therefore, a series of mixed-charge hyperbranched polymer nanoparticles (MCHPNs) with selective antibacterial action were designed and synthesized. Owing to inherent differences in membrane potential among diverse species and high hydrophilicity (Kow = 0.04), the optimal nanoparticles exhibited exceptional selective bactericidal effects over mammalian cells (selectivity index >564) and significantly delayed the emergence of bacterial resistance. Importantly, they endowed surfaces with the ability to impede biofilm formation and mitigate infection-related immune responses. Furthermore, the above findings focus on addressing the problem of AMR in Post-Pandemic, which will for sure attract attention from both academic and industry research.

Effect of Propionate on Citrobacter rodentium Infection in Mice by Regulating NleH Expression

Propionate is one of the main short chain fatty acids in the gut. Previously, we found that propionate significantly down-regulated the expression of NleH. NleH is a virulence effector secreted by Citrobacter rodentium (C. rodentium, C.r.) and is essential for its intestinal colonisation and infection. Therefore, this study intends to explore the effect and mechanism of propionate on C.r. infection by regulating the expression of NleH. Wild-type C.r. and its NleH mutant (C.r.△NleH), E.coli and its NleH1 mutant (E.coli△NleH1) were co-cultured with propionate separately, changes in strain growth and invasion adhesion were detected. Meanwhile, C57BL/6J mice were infected with C.r. and C.r.△NleH to establish animal model, and propionate intervention was given. Through detecting the invasive and infectious ability of strains in mice and the changes related to colon inflammation, to analyse the effect of propionate on C.r. infection by regulating NleH expression. The results showed that propionate can reduce the adhesion of C.r. and intestinal damage by down-regulating NleH expression, meanwhile changes of microbial functional metabolism enhance the resistance to C.r. infection in mice.

Targeting PilA in Acinetobacter baumannii: A Computational Approach for Anti-Virulent Compound Discovery

Acinetobacter baumannii (A. baumannii) has emerged as a critical global pathogen due to its ability to acquire resistance traits. This bacterium exhibits two distinct forms of motility: twitching, mediated by type IV pili (T4P), and surface-associated motility, independent of appendages. T4P is crucial in various bacterial species, facilitating twitching motility, biofilm formation, and host-cell adhesion. The synthesis of T4P is a common feature among Gram-negative pathogens, particularly A. baumannii, suggesting that PilA could be a viable target for biofilm-related treatments. This study aims to develop drug molecules to mitigate A. baumannii virulence by targeting PilA. Using Schrodinger software, we screened 60,766 compounds from the CMNPD, ChemDiv, and Enamine antibacterial databases through high-throughput virtual screening. The top two compounds from each database, identified through extra precision (XP) mode, were subjected to further studies. Among the six compounds identified (CMNPD18469, CMNPD20698, Z2377302405, Z2378175729, N039-0021, and N098-0051), docking scores ranged from - 5.0 to - 7.5 kcal/mol. Subsequently, we conducted 300 ns molecular dynamics simulations and Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) analysis of the PilA-ligand complexes. Analysis of the simulation trajectories indicated structural stability and consistent behavior of the PilA-ligand complexes in a dynamic environment. Notably, the PilA-N098-0051 complex exhibited enhanced stability and robust binding interactions, underscoring its potential as a therapeutic agent. These findings suggest that the identified compounds, particularly N098-0051, hold promise as potent molecules targeting PilA, necessitating further validation through in vitro and in vivo studies.

Clinical diagnostic value of metagenomic next-generation sequencing in patients with acute infection in emergency department

Objective

To explore the value of metagenomic next-generation sequencing (mNGS) and culture in microbial diagnosis of patients with acute infection.

Methods

We retrospectively analyzed 206 specimens from 163 patients who were admitted to the emergency department of The First Affiliated Hospital of Sun Yat-sen University between July 2020, and July 2021. We evaluated the diagnostic efficacy of mNGS and in-hospital traditional culture.

Results

The total positive rate of mNGS was significantly higher than that culture methods (71.4 % vs 40.8 %, p < 0.001), while the sensitivity and accuracy of mNGS were found to be 92.9 % and 88.2 % respectively. However, culture exhibited superior specificity with a value of 92.6 % compared to 75.9 % for mNGS. The detection efficiency of mNGS and culture for fungi was comparable, but mNGS showed superior performance for bacterial detection. In the analysis of sepsis samples, mNGS outperformed traditional culture methods in diagnosing various types of samples, especially for sputum and bronchoalveolar lavage fluid. Among the identified infections, bacterial infections were the most common single infection (37.5 %). Additionally, bacterial-fungal infections represented the most prevalent form of mixed infection (77.3 %). Candida albicans and Staphylococcus aureus were identified as the predominant pathogens in the survival and death groups, respectively. No significant differences in microbial diversity were observed.

Conclusion

Compared to culture methods, mNGS demonstrates superior positive rates, sensitivity, and accuracy in the rapid detection of acute infections, particularly in critically ill patients such as those with sepsis. This capability establishes a foundation for the swift and precise identification of pathogens, allowing for the analysis of clinical indicators and patient prognosis based on the extensive data generated from mNGS.

Pseudorabies virus infection increases the permeability of the mammalian respiratory barrier to facilitate Pasteurella multocida infection

Interaction between viruses and bacteria during the development of infectious diseases is a complex question that requires continuous study. In this study, we explored the interactions between pseudorabies virus (PRV) and Pasteurella multocida (PM), which are recognized as the primary and secondary agents of porcine respiratory disease complex (PRDC), respectively. In vivo tests using mouse models demonstrated that intranasal inoculation with PRV at a sublethal dose induced disruption of murine respiratory barrier and promoted the invasion and damages caused by PM through respiratory infection. Inoculation with PRV also disrupted the barrier function of murine and porcine respiratory epithelial cells, and accelerated the adherence and invasion of PM to the cells. In mechanism, PRV infection resulted in decreased expression of tight junction proteins (ZO-1, occludin) and adherens junction proteins (β-catenin, E-cadherin) between neighboring respiratory epithelial cells. Additionally, PRV inoculation at an early stage downregulated multiple biological processes contributing to epithelial adhesion and barrier functions while upregulating signals beneficial for respiratory barrier disruption (e.g., the HIF-1α signaling). Furthermore, PRV infection also stimulated the upregulation of cellular receptors (CAM5, ICAM2, ACAN, and DSCAM) that promote bacterial adherence. The data presented in this study provide insights into the understanding of virus-bacteria interactions in PRDC and may also contribute to understanding the mechanisms of secondary infections caused by different respiratory viruses (e.g., influenza virus and SARS-CoV-2) in both medical and veterinary medicine.

IMPORTANCE

Co-infections caused by viral and bacterial agents are common in both medical and veterinary medicine, but the related mechanisms are not fully understood. This study investigated the interactions between the zoonotic pathogens PRV and PM during the development of respiratory infections in both cell and mouse models, and reported the possible mechanisms which included: (i) the primary infection of PRV may induce the disruption and/or damage of mammal respiratory barrier, thereby contributing to the invasion of PM; (ii) PRV infection at early stage accelerates the transcription and/or expression of several cellular receptors that are beneficial for bacterial adherence. This study may shed a light on understanding the mechanisms on the secondary infection of PM promoted by different respiratory viruses (e.g., influenza virus and SARS-CoV-2) in both medical and veterinary medicine.

Penicillin Allergy in China: Consequences of Inappropriate Skin Testing Practices and Policies

Penicillins are the most frequently prescribed class of medications worldwide and first-line antibiotic of choice for most bacterial infections. They are also commonly labelled as the culprit of drug 'allergy'; leading to obligatory use of second-line antibiotics, suboptimal antibiotic therapy and increased antimicrobial resistance. However, the majority of reported penicillin 'allergy' labels are found to be incorrect after allergy testing, emphasising the importance of proper drug allergy testing and evaluation. Penicillin skin testing (PST) remains an important component of drug allergy diagnosis; however, its practice and policies significantly differ across the world. Inappropriate and non-evidence-based PST practices can lead to consequences associated with allergy mislabelling. Even within different regions of China, with a population exceeding 1.4 billion, there are marked differences in the implementation, execution and interpretation of PST. This review aims to examine the differences in PST between Mainland China, Hong Kong and the rest of the world. We critically analyse the current practice of 'pre-emptive' PST in Mainland China, which has a significant false-positive rate leading to high levels of penicillin allergy mislabelling. Non-evidence-based practices further compound the high false-positive rates of indiscriminatory PST. We postulate that inappropriate PST policies and practices may exacerbate the mislabelling of penicillin allergy, leading to unnecessary overuse of inappropriate second-line antibiotics, increasing antimicrobial resistance and healthcare costs. We advocate for the importance of more collaborative research to improve the contemporary workflow of penicillin allergy diagnosis, reduce mislabelling and promote the dissemination of evidence-based methods for allergy diagnosis.

Inhalable Polymeric Microparticles for Phage and Photothermal Synergistic Therapy of Methicillin-Resistant Staphylococcus aureus Pneumonia

Acute methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is a common and serious lung infection with high morbidity and mortality rates. Due to the increasing antibiotic resistance, toxicity, and pathogenicity of MRSA, there is an urgent need to explore effective antibacterial strategies. In this study, we developed a dry powder inhalable formulation which is composed of porous microspheres prepared from poly(lactic-co-glycolic acid) (PLGA), internally loaded with indocyanine green (ICG)-modified, heat-resistant phages that we screened for their high efficacy against MRSA. This formulation can deliver therapeutic doses of ICG-modified active phages to the deep lung tissue infection sites, avoiding rapid clearance by alveolar macrophages. Combined with the synergistic treatment of phage therapy and photothermal therapy, the formulation demonstrates potent bactericidal effects in acute MRSA pneumonia. With its long-term stability at room temperature and inhalable characteristics, this formulation has the potential to be a promising drug for the clinical treatment of MRSA pneumonia.

Rapid identification of bloodstream infection pathogens and drug resistance using Raman spectroscopy enhanced by convolutional neural networks

Bloodstream infections (BSIs) are a critical medical concern, characterized by elevated morbidity, mortality, extended hospital stays, substantial healthcare costs, and diagnostic challenges. The clinical outcomes for patients with BSI can be markedly improved through the prompt identification of the causative pathogens and their susceptibility to antibiotics and antimicrobial agents. Traditional BSI diagnosis via blood culture is often hindered by its lengthy incubation period and its limitations in detecting pathogenic bacteria and their resistance profiles. Surface-enhanced Raman scattering (SERS) has recently gained prominence as a rapid and effective technique for identifying pathogenic bacteria and assessing drug resistance. This method offers molecular fingerprinting with benefits such as rapidity, sensitivity, and non-destructiveness. The objective of this study was to integrate deep learning (DL) with SERS for the rapid identification of common pathogens and their resistance to drugs in BSIs. To assess the feasibility of combining DL with SERS for direct detection, erythrocyte lysis and differential centrifugation were employed to isolate bacteria from blood samples with positive blood cultures. A total of 12,046 and 11,968 SERS spectra were collected from the two methods using Raman spectroscopy and subsequently analyzed using DL algorithms. The findings reveal that convolutional neural networks (CNNs) exhibit considerable potential in identifying prevalent pathogens and their drug-resistant strains. The differential centrifugation technique outperformed erythrocyte lysis in bacterial isolation from blood, achieving a detection accuracy of 98.68% for pathogenic bacteria and an impressive 99.85% accuracy in identifying carbapenem-resistant Klebsiella pneumoniae. In summary, this research successfully developed an innovative approach by combining DL with SERS for the swift identification of pathogenic bacteria and their drug resistance in BSIs. This novel method holds the promise of significantly improving patient prognoses and optimizing healthcare efficiency. Its potential impact could be profound, potentially transforming the diagnostic and therapeutic landscape of BSIs.

The nasal microbiota is a potential diagnostic biomarker for sepsis in critical care units

This study aimed to characterize the composition of intestinal and nasal microbiota in septic patients and identify potential microbial biomarkers for diagnosis. A total of 157 subjects, including 89 with sepsis, were enrolled from the affiliated hospital. Nasal swabs and fecal specimens were collected from septic and non-septic patients in the intensive care unit (ICU) and Department of Respiratory and Critical Care Medicine. DNA was extracted, and the V4 region of the 16S rRNA gene was amplified and sequenced using Illumina technology. Bioinformatics analysis, statistical processing, and machine learning techniques were employed to differentiate between septic and non-septic patients. The nasal microbiota of septic patients exhibited significantly lower community richness (P = 0.002) and distinct compositions (P = 0.001) compared to non-septic patients. Corynebacterium, Staphylococcus, Acinetobacter, and Pseudomonas were identified as enriched genera in the nasal microbiota of septic patients. The constructed machine learning model achieved an area under the curve (AUC) of 89.08, indicating its efficacy in differentiating septic and non-septic patients. Importantly, model validation demonstrated the effectiveness of the nasal microecological diagnosis prediction model with an AUC of 84.79, while the gut microecological diagnosis prediction model had poor predictive performance (AUC = 49.24). The nasal microbiota of ICU patients effectively distinguishes sepsis from non-septic cases and outperforms the gut microbiota. These findings have implications for the development of diagnostic strategies and advancements in critical care medicine.IMPORTANCEThe important clinical significance of this study is that it compared the intestinal and nasal microbiota of sepsis with non-sepsis patients and determined that the nasal microbiota is more effective than the intestinal microbiota in distinguishing patients with sepsis from those without sepsis, based on the difference in the lines of nasal specimens collected.

Tackling antimicrobial resistance in sub-Saharan Africa: challenges and opportunities for implementing the new people-centered WHO guidelines

INTRODUCTION

Antimicrobial drugs form an essential component of medical treatment in human and animal health. Resistance associated with their use has posed a global public health threat. Multiple efforts have been made at the global level directed by the World Health Organization and associated partners to develop policies aimed at combatting antimicrobial resistance.

AREAS COVERED

Whilst the Global Action Plan on antimicrobial resistance and people-centered framework aim to guide countries in implementing successful antimicrobial resistance policies, their adoption and success depend on different implementation contexts. Therefore, this paper highlights the challenges and opportunities for implementing the World Health Organization's people-centered approach in sub-Saharan Africa, whilst recognizing antimicrobial resistance as a multifaceted problem rooted in 'complex systems.'

EXPERT OPINION

The people-centered approach provides a solid framework for combating antimicrobial resistance. Countries should build sustainable national action plans, adopt the One Health approach, limit over-the-counter antibiotic consumption, and educate communities on rational antibiotic use. They should also promote inter-country collaborations and innovative solutions, strengthen drug regulatory capacities, invest in infection control, water sanitation, hygiene, diagnostics, and surveillance tools, and promote vaccine uptake to prevent drug-resistant infections.

Antifungal potential of multi-drug-resistant Pseudomonas aeruginosa: harnessing pyocyanin for candida growth inhibition

Introduction

Pseudomonas aeruginosa is notorious for its multidrug resistance and its involvement in hospital-acquired infections. In this study, 20 bacterial strains isolated from soil samples near the Hindan River in Ghaziabad, India, were investigated for their biochemical and morphological characteristics, with a focus on identifying strains with exceptional drug resistance and pyocyanin production.

Methods

The isolated bacterial strains were subjected to biochemical and morphological analyses to characterize their properties, with a particular emphasis on exopolysaccharide production. Strain GZB16/CEES1, exhibiting remarkable drug resistance and pyocyanin production. Biochemical and molecular analyses, including sequencing of its 16S rRNA gene (accession number LN735036.1), plasmid-curing assays, and estimation of plasmid size, were conducted to elucidate its drug resistance mechanisms and further pyocynin based target the Candida albicans Strain GZB16/CEES1 demonstrated 100% resistance to various antibiotics used in the investigation, with plasmid-curing assays, suggesting plasmid-based resistance gene transmission. The plasmid in GZB16/CEES1 was estimated to be approximately 24 kb in size. The study focused on P. aeruginosa's pyocyanin production, revealing its association with anticandidal activity. The minimum inhibitory concentration (MIC) of the bacterial extract against Candida albicans was 50 μg/ml, with a slightly lower pyocyanin-based MIC of 38.5 μg/ml. Scanning electron microscopy illustrated direct interactions between P. aeruginosa strains and Candida albicans cells, leading to the destruction of the latter.

Discussion

These findings underscore the potential of P. aeruginosa in understanding microbial interactions and developing strategies to combat fungal infections. The study highlights the importance of investigating bacterial-fungal interactions and the role of pyocyanin in antimicrobial activity. Further research in this area could lead to the development of novel therapeutic approaches for combating multidrug-resistant infections.

Respiratory pathogenic microbial infections: a narrative review

Respiratory infectious diseases have long been recognised as a substantial global healthcare burden and are one of the leading causes of death worldwide, particularly in vulnerable individuals. In the post COVID-19 era, there has been a surge in the prevalence of influenza virus A and other multiple known viruses causing cold compared with during the same period in the previous three years, which coincided with countries easing COVID-19 restrictions worldwide. This article aims to review community-acquired respiratory illnesses covering a broad spectrum of viruses, bacteria, and atypical microorganisms and focuses on the cluster prevalence of multiple known respiratory pathogens in China, thereby providing effective prevention and control measures.