Systemic sepsis is a life-threatening syndrome driven by a dysregulated host response, leading to immune functional disorders, gut microbiota dysbiosis, and multi-organ failure. Previous studies have demonstrated that Musca domestica cecropin (MDC) and eugenol (EO) possess antibacterial, anti-inflammatory, and immunomodulatory activities, offering an approach to infection control. However, it is the vulnerability of therapeutic agents to the harsh gastrointestinal environment that severely limits the efficacy of oral delivery. To address these challenges, we developed a pH-responsive hydrogel microsphere system (MDC/EO/PDA-SA) for oral administration to treat systemic sepsis. This system comprises polydopamine (PDA) nanoparticles co-loaded with MDC and EO, encapsulated within a sodium alginate (SA) hydrogel matrix, leveraging the reliable pH-responsive behavior of SA for site-specific delivery. In vitro studies confirmed its controlled release profile: in Simulated Gastric Fluid (SGF), 24-hour release rates were minimal (19.96% for MDC and 14.42% for EO), whereas in Simulated Intestinal Fluid (SIF), they reached 72.95% for MDC and 64.03% for EO, demonstrating robust protection against gastric degradation and pH-responsive behavior. In a cecal ligation and puncture (CLP)-induced systemic sepsis model, MDC/EO/PDA-SA treatment significantly increased the survival rate to 66.6%. The system markedly reduced intestinal TNF-α and IL-6 levels (by 65.9% and 52.1%, respectively) and normalized myeloperoxidase (MPO) activity. Collectively, the treatment effectively alleviated systemic inflammation, mitigated oxidative stress, modulated immune responses, and restored intestinal homeostasis. These findings demonstrate that MDC/EO/PDA-SA provides effective intestinal-targeted delivery and multi-level therapeutic regulation, representing a promising oral strategy for the management of systemic sepsis.

Background: Other infectious diarrhea (OID) is a heterogeneous public health syndrome in China that includes viral and bacterial enteric infections, with norovirus as a major contributor in many outbreak settings. Although pandemic-era nonpharmaceutical interventions altered gastrointestinal infection dynamics in many countries, long-term city-level evidence from subtropical China on seasonal redistribution, structural breakpoints, and environmental response remains limited. Methods: We conducted a retrospective ecological time-series study using routine surveillance data from Shenzhen, China, during January 2013-July 2025. Daily OID counts from the China Information System for Disease Control and Prevention were aggregated to monthly counts for seasonal comparison, breakpoint detection, and interrupted time-series analyses. Laboratory-confirmed norovirus detections were analyzed as GI, GII, and mixed GI+GII series. We compared descriptive seasonal distributions across predefined pre-COVID, during-COVID, and post-COVID periods, identified the most strongly supported breakpoint using segmented models, Bayesian information criterion, Chow tests, and Bayesian breakpoint search, and examined breakpoint-stratified temperature-humidity response surfaces. Results: Across 151 months, 578,222 OID cases were reported. Mean monthly OID counts increased from 3,019.4 before COVID to 3,290.1 during COVID and 6,649.9 after 2022. Monthly distributions differed significantly across descriptive periods for OID and all norovirus analytic series. January 2022 was the best-supported structural breakpoint. In seasonally adjusted interrupted time-series analysis, the monthly trend increased from 16.2 cases per month before the breakpoint to 181.1 cases per month afterward. Environmental response patterns also changed after the breakpoint: aggregated OID showed reduced explanatory power of a simple temperature-humidity surface, whereas genotype-stratified norovirus series showed heterogeneous post-break changes. Conclusions: OID activity in Shenzhen did not simply return to its pre-pandemic pattern. Instead, the series showed a marked transition beginning in January 2022, with redistributed seasonality, accelerated growth, and subtype-specific changes in estimated meteorologic response. Post-COVID enteric-disease surveillance and early warning models should therefore be recalibrated using recent local data and strengthened pathogen-specific laboratory information.

BACKGROUND:In July 2025, a large chikungunya outbreak occurred in southern China, with more than 5000 cases reported within a single month. However, the genomic basis of this urban outbreak remains poorly characterized. METHODS:A total of 804 CHIKV-positive clinical specimens were collected through routine surveillance and outbreak investigations by the Shenzhen Center for Disease Control and Prevention. Following whole-genome sequencing and quality control, 614 genomes were retained and analyzed in combination with 1105 publicly available CHIKV genomes sampled globally between 1953 and 2025. Comprehensive genetic analyses were performed to characterize lineage origin, transmission dynamics, and short-term genomic diversification across local and global scales. RESULTS:All outbreak sequences belonged to the East/Central/South African (ECSA) lineage, specifically clustering within the Middle African lineage (MAL) sub-lineage, and formed a well-supported, genetically compact monophyletic group. Within this cluster, genomes diversified rapidly into multiple co-circulating subclusters over a short time window (August-October), indicating continued regional transmission and geographic structuring during outbreak expansion. Despite this rapid expansion, genetic variation remained limited, with only a small number of characteristic amino-acid substitutions identified, most of which were present at low to moderate frequencies and showed no evidence of widespread fixation across the outbreak population. The inferred substitution rate for the outbreak-associated lineage was 9.90 × 10⁻⁴ substitutions per site per year (95% HPD: 8.28-11.69 × 10⁻⁴). CONCLUSIONS:These findings suggest that large CHIKV outbreaks in highly connected metropolitan settings can arise from the rapid expansion of a single contemporary genetic background, even in the absence of extensive adaptive change. This study provides a high-resolution genomic perspective on CHIKV spread and highlights key features of short-term viral diversification during outbreaks.

Current clinical strategies for Methicillin-resistant Staphylococcus aureus (MRSA)-induced acute lung injury (ALI) predominantly focus on single-approach interventions such as anti-inflammatory therapy. However, due to the complex, multi-pathway pathological network underlying the disease, targeting a single pathway often yields suboptimal therapeutic outcomes. Consequently, there is a pressing need to develop innovative drug delivery systems capable of systematically addressing this intricate pathological process. Geraniol, a naturally derived monoterpene alcohol, exhibits multiple pharmacological activities including antimicrobial, antioxidant, and organ-protective effects, while the antimicrobial peptide (AMP) FK13-a1 demonstrates broad-spectrum antibacterial, anti-inflammatory, and immunomodulatory functions. Recognizing their complementary mechanisms of action, we innovatively propose a synergistic therapeutic strategy combining geraniol with FK13-a1. To enhance targeting precision, we engineered a biomimetic delivery system by coating nanomaterials with macrophage membranes via tyramine linkage, enabling specific homing to pulmonary inflammatory sites. Guided by this design concept, we successfully fabricated the biomimetic nanodrug Tyr-MM@PLGA/G+F and conducted systematic characterization using multiple analytical techniques. Through established in vitro and in vivo infection models, we evaluated the therapeutic efficacy of this nanosystem. Results demonstrated that Tyr-MM@PLGA/G+F actively targets ALI lesion sites, achieving precise co-delivery and synergistic action of geraniol and FK13-a1 at the pathological foci, thereby significantly enhancing treatment outcomes. This study not only validates the remarkable efficacy of this composite nanosystem against ALI but also provides novel insights and experimental evidence for targeted therapy of this condition.

Bacterial-infected wounds impose a substantial burden worldwide, with polymicrobial infections exacerbating the complexity of healing through dysregulated pH environments and gelatinase-mediated matrix degradation. Herein, we developed a microenvironment-responsive microneedle (MN) patch utilizing a "dynamic warning-graded intervention" strategy. The patch incorporates (a) a bromothymol blue-based pH visual warning system that detects acid-base changes during both acute and chronic infections, (b) a gelatin methacryloyl and exosome matrix material that enables enzyme-triggered release of human bone marrow mesenchymal stem cell-derived exosomes, responding to pathological gelatinase for spatiotemporal drug delivery, and (c) triple therapeutic payloads [hemostasis (halloysite nanotubes)/antibacterial and anti-inflammatory (antimicrobial peptides)/scar reduction (salvianolic acid B)]. In vitro validation demonstrated a bacterial clearance rate exceeding 95% against methicillin-resistant Staphylococcus aureus/imipenem-resistant Pseudomonas aeruginosa, with biofilm inhibition and disruption rates both surpassing 90%. In vivo experiments demonstrated that MNs showed observable changes in wound color within 8 h in both infectious acute and chronic wounds. In acute wounds, nearly complete healing was achieved within 10 d. By coordinating hemostasis (platelet activation within 60 s), controlling inflammation (62.07% down-regulation of tumor necrosis factor-α), and promoting angiogenesis (2.51-fold up-regulation of CD31), the healing rate of diabetic ulcers was accelerated by 9.20% compared to clinical dressings. This platform provides a foundation for integrating real-time diagnosis and treatment in complex wound management.

Candida vaginitis (CV) is the most common fungal infection among gynecological diseases, caused by Candida albicans (C. albicans). Traditional treatment for CV has led to increased antibiotic resistance, complicating treatment and indiscriminately killing both pathogens and beneficial bacteria in the vagina. Additionally, the inconvenience of traditional vaginal administration and the short residence time of treatments pose significant challenges. We developed a safe and effective combination drug delivery platform featuring magnetic bilayer gel microspheres to combine antibacterial properties and maintain the balance of the microbial community. This platform was characterized through a series of in vitro tests evaluating its dissolution, adherence, and retention properties, graded slow release, and antimicrobial effects. In vivo studies using CV mice models were conducted to assess antifungal properties, microecological regulation, magnetic residency, safety, and other related aspects. The results demonstrated that the material effectively inhibits the growth of C. albicans. It also increases the drug's residence time in the body and successfully releases probiotics, thereby improving vaginal microecology and promoting the recovery of inflammation to normal levels. These findings suggest a novel therapeutic approach for managing C. albicans vaginitis.

BACKGROUND:Infections caused by foodborne pathogens pose a major threat to human health. Traditional bacterial detection methods, such as plate culture and polymerase chain reaction, cannot meet the growing demand for fast and accurate detection. In contrast, colorimetric sensors have the characteristics of convenience, speed, and visualization, but their specific sensitivity is relatively poor. Therefore, it is necessary to develop a biosensor with selective identification of foodborne pathogens, high sensitivity, and early detection of foodborne pathogen contamination in food. RESULTS:We have developed a broad-spectrum microbial detection biosensor platform MDC@N-MMCNs that combines antimicrobial peptides as identifying ingredients with mesoporous carbon with peroxidase-like activity to detect and eliminate foodborne pathogens rapidly. In this study, nitrogen-doped magnetic mesoporous carbon nanospheres (N-MMCNs) were prepared using ferric nitrate as the magnetic source. Musca domestica cecropin (MDC) has abundant recognition sites on the surface of bacteria, which helps to recognize and amplify the signal, and combines with N-MMCNs to form MDC@N-MMCNs. MDC@N-MMCNs have high stability, specificity, and sensitivity, with a visual detection limit as low as 102 CFU/mL. The MDC@N-MMCNs paper-based sensor enables selective and rapid detection of four foodborne pathogens via a smartphone application. SIGNIFICANCE:Based on these findings, we believe that MDC@N-MMCNs hold great potential for on-site bacterial infection diagnosis in resource-limited environments or point-of-care (POCT) settings, offering a simple, cost-effective solution for food safety and public health.

The study aimed to investigate epidemiological profile and molecular characteristics of coxsackievirus A10 (CVA10) associated with hand, foot and mouth disease (HFMD) in Shenzhen, China and comparatively analyze genomes of CVA10 strains related to differential clinical phenotypes. A total of 3170 clinical specimens collected between 2021 and 2024 were examined for CVA10 using real-time RT-PCR. Complete VP1 sequences and near-complete genome sequences of CVA10 were determined by RT-PCR methods and sequencing. Sequences were analyzed using a series of bioinformatics programs. Two (33.33%) out of 6 severe cases were infected with CVA10. The detection rate of CVA10 associated with mild HFMD ranged from 1.21% to 6.11% in 2021-2024, with an overall detection rate of 3.73%. There was no significant difference in the infection rate of CVA10 between males and females or different age groups. The CVA10 infections mainly occurred in Spring (March to May) and Summer (June to August) in Shenzhen. Of the 74 VP1 sequences determined, 71 (95.95%) of them were detected in the sub-genotype C2, 3 (4.05%) were assigned to the genotype D. Genomic sequence analysis indicated that the genotype D of CVA10 of this study derived from genetic recombination between CVA10 and CVA16 in 3A-3D coding region (nucleotide position: 5075-6896). Different variable sites were observed in the two CVA10 strains associated with different severe complications when compared to CVA10 strains associated with mild diseases. In conclusion, CVA10 associated with HFMD circulated at a low level in Shenzhen in 2021-2024, with C2 as the predominant genotype. Recombinant genotype D of CVA10 was introduced first to Shenzhen in 2024. The study emphasizes the importance of continuous molecular surveillance of CVA10.

Key amino acid mutations in SARS-CoV-2 genomes drive the emergence of variants of concern, impacting virus transmission and immune escape. However, there is still a lack of large-scale monitoring and risk assessment of new amino acid variants in sewage. To address this gap, we developed eVarEPS (Environmental SARS-CoV-2 Variations Evaluation and Prewarning System), a system for the early identification and assessment of SARS-CoV-2 variants in environmental samples. We identified new amino acid mutations in 27,762 sewage sequencing datasets from public databases and published literature and carried out risk assessment of these variants. In addition, we collected 1976 sewage samples and 3817 human samples from Shenzhen from November 2022 to January 2024, employing eVarEPS to monitor and assess the risk of new variants. Using eVarEPS, we detected 5543 unique amino acid variants in global sewage samples, and multi-dimensional risk assessment of amino acid variants suggested that the variants with strong receptor affinity, weak neutralizing antibody affinity, and low difficulty of amino acid change were more likely to spread in the population (P < 0.01). We identified 1345 high-risk variants specifically identified in sewage, which should be focused on. We identified variants detected in sewage an average of 147 days earlier than in human populations, with 46.62% of these new amino acid variants subsequently spreading in the population. In addition, risk assessment showed amino acid variations with higher risk are more likely to prevail in the population (64.93 %, P < 0.001). Application of eVarEPS in the Shenzhen region, we detected the characteristic 19 amino acid variants of major lineages in Shenzhen sewage, one month to one year earlier than the discovery of the corresponding lineages. We conclude that tracking new SARS-CoV-2 amino acid variants in sewage offers more sensitive and timely insights into population prevalence. High-risk mutations identified by eVarEPS are more likely to spread and should be closely monitored. This study enhances our understanding of SARS-CoV-2 variation dynamics and provides an efficient method for future pathogen monitoring and early warning. eVarEPS has been developed into a database and online tool that can be freely accessed at https://nmdc.cn/ncovn/analyze/eVarEPS.

Introduction:The emergence of the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineage, BA.2.86, has sparked global public health concerns for its potential heightened transmissibility and immune evasion. Utilizing data from Shenzhen's city-wide wastewater surveillance system, we highlight the presence of the BA.2.86 lineage in Shenzhen.Methods:A mediator probe polymerase chain reaction (PCR) assay was developed to detect the BA.2.86 lineage in wastewater by targeting a specific mutation (Spike: A264D). Between September 19 and December 10, 2023, 781 wastewater samples from 38 wastewater treatment plants (WWTPs) and 9 pump stations in ten districts of Shenzhen were examined. Through multiple short-amplicon sequencing, three positive samples were identified.Results:The BA.2.86 lineage was identified in the wastewater of Futian and Nanshan districts in Shenzhen on December 2, 2023. From December 2 to 10, a total of 21 BA.2.86-positive wastewater samples were found across 6 districts (Futian, Nanshan, Longhua, Baoan, Longgang, and Luohu) in Shenzhen. The weighted average viral load of the BA.2.86 lineage in Shenzhen's wastewater was 43.5 copies/L on December 2, increased to 219.8 copies/L on December 4, and then decreased to approximately 100 copies/L on December 6, 8, and 10.Conclusions:The mediator probe PCR assay, designed for swift detection of low viral concentrations of the BA.2.86 lineage in wastewater samples, shows promise for detecting different SARS-CoV-2 variants. Wastewater surveillance could serve as an early detection system for promptly identifying specific SARS-CoV-2 variants as they emerge.

Ventilator-associated pneumonia (VAP) is a common healthcare-acquired infection often arising during artificial ventilation using endotracheal intubation (ETT), which offers a platform for bacterial colonization and biofilm development. In particular, the effects of prolonged COVID-19 on the respiratory system. Herein, we developed an antimicrobial coating (FK-MEM@CMCO-CS) capable of visualizing pH changes based on bacterial infection and releasing meropenem (MEM) and FK13-a1 in a controlled manner. Using a simple dip-coating process with controlled loading, chitosan was cross-linked with sodium carboxymethyl cellulose oxidation (CMCO) and coated onto PVC-based ETT to form a hydrogel coating. Subsequently, the coated segments were immersed in an indicator solution containing bromothymol blue (BTB), MEM, and FK13-a1 to fabricate the FK-MEM@CMCO-CS coating. In vitro studies have shown that MEM and FK13-a1 can be released from coatings in a pH-responsive manner. Moreover, anti-biofilm and antibacterial adhesion results showed that FK-MEM@CMCO-CS coating significantly inhibited biofilm formation and prevented their colonization of the coating surface. In the VAP rat model, the coating inhibited bacterial growth, reduced lung inflammation, and had good biocompatibility. The coating can be applied to the entire ETT and has the potential for industrial production.

目的 了解广东省深圳市疱疹性咽峡炎(HA)病原组成与病原体的分子特征,为HA的预防与控制提供科学依据.方法 2017-2018年收集了 157例HA患者的314份临床样本,其中粪便样本和咽拭子各157份.使用荧光定量逆转录-聚合酶链反应(RT-PCR)和基于半巢式RT-PCR扩增的测序方法对肠道病毒(EV)进行检测与分型.使用生物信息学软件对病毒VP1基因进行序列分析.结果 在126例(80.30％,126/157)EV阳性的患者中,共检出10种EV,检出率最高的是柯萨奇病毒A 组 10 型(CVA10)(19.70％,31/157),其次是 CVA4(17.80％,28/157)、CVA6(15.30％,24/157)和 CVA2(10.80％,17/157),其他病原体包括 CVA5(4.50％,7/157)、CVA 16(3.20％,5/157)、EV-A71(1.30％,2/157)、CVA8(0.60％,1/157)、CVB5(0.60％,1/157)和埃可病毒11(E11)(0.60％,1/157),1例为CVA4与CVA10的混合感染(0.60％,1/157).2017年检出率最高的两种病原体是CVA2和CVA6,而2018年却是CVA10和CVA4.粪便样本与咽拭子的病原检出率之间的差异没有统计学意义(x2=0.019,P=0.892).基于VP1序列的分子系统发育分析表明,本研究CVA10毒株均为C2基因型.CVA4除了 1株为C5基因型外,其余均为C2基因型.1株CVA6毒株位于先前未描述的进化分支,其他CVA6毒株均为D3a基因亚型.CVA2毒株均为D2基因型.结论 粪便样本与咽拭子都适用于HA的病原体核酸检测.CVA10、CVA4、CVA6和CVA2是2017-2018年深圳市HA的优势病原体,大部分毒株是我国主流基因型,个别毒株处于不常见的基因型或进化分支.

目的 探讨2021年深圳地区疱疹性咽峡炎的流行病学和病原学特征,为疱疹性咽峡炎的防控提供科学参考.方法 收集2021年深圳地区哨点医院210例疱疹性咽峡炎病例的基本信息及其咽拭子、肛拭子和粪便样本408份.采用荧光定量PCR进行肠道病毒检测,采用半巢式PCR结合测序分析进行肠道病毒分型.结果 210例疱疹性咽峡炎患者年龄集中在5岁以下,平均年龄(2.7±1.7)岁,疾病流行高峰在春季,患者的主要临床表现为发热和口腔疱疹.咽拭子和肛拭子样本的阳性率一致且一致性较高(Kappa=0.785,P=1.000).粪便样本的检出阳性率高于咽拭子,差异有统计学意义(x2=12.000,P＜0.001).总肠道病毒阳性率为84.8％,共检测出7种肠道病毒,包括柯萨奇病毒 A2 型(CV-A2)、CV-A4、CV-A5、CV-A6、CV-A10、CV-A16和CV-B3,其中CV-A4(38.8％)和CV-A10(35.4％)占比较高.不同月份的病原分布不同,差异有统计学意义(x2=115.344,P＜0.001).感染CV-A16患者出现发热症状的比例低于其他病原体,差异有统计学意义(x2=11.005,P＜0.05).感染CV-A2患者发热体温高于其他病原体,差异有统计学意义(F=2.658,P＜0.05).结论 2021年深圳地区疱疹性咽峡炎发病人群以5岁以下为主,春季为流行高峰,感染肠道病毒主要为CV-A4和CV-A10,需加强柯萨奇病毒的监测.

This paper comprehensively analyses the first-ever monkeypox outbreak in Shenzhen, China, encompassing clinical symptomatology, therapeutic approaches, epidemiological research, and comprehensive laboratory tests, aiming to establish a robust reference for future monkeypox mitigation and management strategies. The investigation involved a thorough investigation of all identified positive cases, including extensive molecular analysis by nucleic acid detection and whole-genome sequencing of the monkeypox virus. Contact tracing and containment of the infected individuals were also undertaken. Three distinct monkeypox cases were identified in this unique outbreak, exhibiting mild and atypical clinical manifestations, primarily fever and rash. All cases were associated with a single transmission chain, primarily facilitated through close contact and homosexual behavior, indicative of a high-risk factor for monkeypox transmission.

Objective:To understand the molecular epidemiological features of norovirus outbreaks in Shenzhen of China from January 2019 to December 2021.Methods:The norovirus outbreaks information and specimen from January 2019 to December 2021 were collected. Norovirus was detected by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Positive samples were amplified by RT-PCR and sequenced. The sequences were then analyzed. Genome amplification and sequence analysis were performed on three strains of GII.2 [P16].Results:From January 2019 to December 2021, a total of 246 outbreaks caused by norovirus were reported, mainly in kindergartens (132, 53.66%) and primary schools (52, 21.14%). The number of cases in an outbreak ranged from 3 to 130, with a median value of 8. The epidemic peak of norovirus outbreak was from November to the next March. The viruses in 211 outbreaks were successfully genotyped. Seven genotypes of GI group and eleven genotypes of GII group were detected. Norovirus GII.2[P16] was responsible for 78 (36.97%) outbreaks. According to the genome analysis of GII.2[P16], the strains from the outbreaks in 2020 still belonged to GII.2[2016](2016-2017) subcluster. Amino acid mutations were observed in the non-structural protein P22 (L777S) and 3C protease (A1047V and P1074T).Conclusions:GII.2[P16] was the predominant genotype that caused the outbreak of norovirus in Shenzhen from January 2019 to December 2021, mainly in kindergartens and schools. Continuous surveillance and genome analysis can help to find the mutations of epidemic strains and the emergence of novel variants.

Background Norovirus (NoV) is the main cause of non-bacterial acute gastroenteritis (AGE) outbreaks worldwide. From September 2015 through August 2018, 203 NoV outbreaks with 2,500 patients were reported to the Shenzhen Center for Disease Control and Prevention. Methods Fecal specimens were collected from the 203 outbreaks and epidemiological data were collected through the AGE outbreak surveillance system in Shenzhen. The genotypes were determined by sequencing analysis. To gain a better understanding of evolutionary characterization of NoV in Shenzhen, the molecular evolution was analyzed by time-scale evolutionary phylogeny and amino acid mutations. Results Most of these outbreaks were associated with NoV GII.P16/GII.2 strain (45.3%,92/203) and occurred in school settings (91.6%,186/203). The timescale phylogeny suggested that the GII.P16/GII.2 strain was recombination strain and were still stable. The amino acid mutations suggested that the nonstructural proteins of the recombination strain might play a more significant role than VP1 gene in these GII.P16/GII.2 recombination strain outbreaks. Conclusions This study illustrated the characteristics of the molecular epidemiological patterns in Shenzhen, China during September 2015 to August 2018 and provided the evidence that the GII.P16/GII.2 strain was static and the epidemic trend had fade.

目的 研究深圳地区急性肠胃炎住院患儿中人副肠孤病毒(HPeV)的临床和流行病学特征.方法 收集2017年1月到2018年12月深圳地区5岁以下急性肠胃炎住院患儿粪便标本(常规细菌鉴定为阴性)497份,实时荧光RT-PCR方法检测HPeV,通过巢式PCR扩增VP3/VP1连接区片段进行分型,同时对患儿的流行病学和临床资料进行统计分析.结果 497例患儿中,HPeV的阳性率为8.2％;男性HPeV阳性率为7.6％,女性HPeV阳性率为9.4％(χ2=0.491,P=0.501);0～6月龄患儿HPeV阳性率最高,且92.7％的HPeV阳性患儿月龄<24个月;深圳夏季(7～9月)HPeV的阳性率最高.HPeV阳性患儿主要临床表现为中热(38.1～39℃),腹泻频率平均>6次/d,以黏液便为主,常伴有呕吐,呕吐频率平均每天5次,呕吐物以胃内容物为主.HPeV阳性患儿较阴性患儿在有无呕吐和呕吐物性状差异具有统计学意义.本研究中共检测到HPeV-1(HPeV-1A和HPeV-1B亚型)、3、4、5、6和14在内的6种基因型,其中HPeV-1B(56.1％)为优势流行株,其次是HPeV-1A(17.1％)、HPeV-3(7.3％)、HPeV-4(7.3％)、HPeV-5(4.9％)、HPeV-6(4.9％)和HPeV-14(2.4％).系统进化分析结果显示,大部分深圳分离株与兰州和广州来源的参考株核苷酸序列一致性高.结论 本研究首次在深圳地区5岁以下急性肠胃炎住院患儿粪便中检测到HPeV,且在2017年和2018年有稳定的感染率,检测到6种HPeV基因型别可能与急性肠胃炎相关,HPeV夏季检出率最高,好发于0～6个月患儿,可能是引起急性肠胃炎住院患儿呕吐胃内容物的病因.开展HPeV监测以更充分地掌握其在深圳地区的流行和临床特征,有助于进一步明确深圳地区住院患儿病毒性急性肠胃炎病原谱构成.

Bioorthogonal metabolic labeling through the endogenous cellular metabolic pathways (e.g., phospholipid and sugar) is a promising approach for effectively labeling live viruses. However, it remains a big challenge to label nonenveloped viruses due to lack of host-derived envelopes. Herein, a novel bioorthogonal labeling strategy is developed utilizing protein synthesis pathway to label and trace nonenveloped viruses. The results show that l-azidohomoalanine (Aha), an azido derivative of methionine, is more effective than azido sugars to introduce azido motifs into viral capsid proteins by substituting methionine residues during viral protein biosynthesis and assembly. The azide-modified EV71 (N3-EV71) particles are then effectively labeled with dibenzocyclooctyl (DBCO)-functionalized fluorescence probes through an in situ bioorthogonal reaction with well-preserved viral infectivity. Dual-labeled imaging clearly clarifies that EV71 virions primarily bind to scavenger receptors and are internalized through clathrin-mediated endocytosis. The viral particles are then transported into early and late endosomes where viral RNA is released in a low-pH dependent manner at about 70 min postinfection. These results first reveal viral trafficking and uncoating mechanisms, which may shed light on the pathogenesis of EV71 infection and contribute to antiviral drug discovery.

目的 了解深圳市坪山区手足口病的病原谱和柯萨奇病毒A组6型(CVA6)基因特征.方法 收集坪山区2019年疑似手足口病的病例粪便或肛拭子样本,采用Real-time RT-PCR法进行肠道病毒核酸检测分型,选取其中的优势型别CVA6阳性样本进行VP1片段全长序列扩增、序列测定和系统进化分析.结果 2019年共检测手足口病病例样本184份,检出肠道病毒通用型阳性165份,总阳性率为89.67％;其次为CVA6阳性120份(72.73％)、CVA16阳性40份(24.24％)、CVA10阳性8份(4.85％),其他肠道病毒阳性3份(1.82％),未检出肠道病毒71型(EV71).同源性及系统进化分析显示,2019年深圳市坪山区24株CVA6 VP1基因核苷酸和氨基酸同源性分别为93.4％～99.9％和98.4％～100.0％,基因型为D3亚型,24株病毒VP1序列均分布于D3a.2分支上.结论 2019年坪山区手足口病病原体以CVA6为主,D3a.2为其优势流行株.

In this study, we investigated the epidemiology and molecular characteristics of enteroviruses associated with severe hand, foot and mouth disease (HFMD) in Shenzhen, China, during 2014-2018. A total of 137 fecal specimens from patients with severe HFMD were collected. Enterovirus (EV) types were determined using real-time reverse transcription polymerase chain reaction (RT-PCR), RT nested PCR, and sequencing. Sequences were analyzed using bioinformatics programs. Of 137 specimens tested, 97 (70.8%), 12 (8.8%), and 10 (7.3%) were positive for EV-A71, coxsackievirus A6 (CVA6), and CVA16, respectively. Other pathogens detected included CVA2 (2.9%, 4/137), CVA10 (2.9%, 4/137), CVA5 (0.7%, 1/137), echovirus 6 (E6) (0.7%, 1/137) and E18 (0.7%, 1/137). The most frequent complication in patients with proven EV infections was myoclonic jerk, followed by aseptic encephalitis, tachypnea, and vomiting. The frequencies of vomiting and abnormal eye movements were higher in EV-A71-infected patients than that in CVA6-infected or CVA16-infected patients. Molecular phylogeny based on the complete VP1 gene revealed no association between the subgenotype of the virus and disease severity. Nevertheless, 12 significant mutations that were likely to be associated with virulence or the clinical phenotype were observed in the 5'UTR, 2Apro, 2C, 3A, 3Dpol and 3'UTR of CVA6. Eight significant mutations were observed in the 5'UTR, 2B, 3A, 3Dpol and 3'UTR of CVA16, and 10 significant mutations were observed in the 5'UTR, VP1, 3A and 3Cpro of CVA10. In conclusion, EV-A71 is still the main pathogen causing severe HFMD, although other EV types can also cause severe complications. Potential virulence or phenotype-associated sites were identified in the genomes of CVA6, CVA16, and CVA10.