Objective Seroconversion or seroclearance of hepatitis B e antigen (HBeAg) is an important serological marker for patients with chronic hepatitis B (CHB) transitioning from a high replication state to a low replication state. This study explores the immune factors associated with HBeAg seroclearance based on a nested case-control study design. Methods ABased on the Wuwei CHB disease-specific cohort, a nested case-control approach was adopted. A total of 28 subjects with HBeAg seroclearance were selected as the case group, and 28 HBeAg persistent positive subjects were contemporaneously matched as the control group by age within 10 years and treatment regimen. Hepatitis B serum markers and immune-related cytokines were analyzed and detected. Logistic regression analysis was used to screen the influencing factors associated with HBeAg seroclearance. Results A total of 28 pairs of HBeAg seroclearance subjects and contemporaneously matched HBeAg persistent subjects were included. The mean age was (40.10 ± 11.03) years, and males accounted for 53.6%. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), direct bilirubin (DBIL), and controlled attenuation parameter (CAP) differed significantly between the two groups (P<0.05). Meanwhile, the levels of C-X-C motif ligand 9 (CXCL9) (Z=2.279, P=0.022) and C-X-C motif ligand 10 (CXCL10) (Z=2.679, P=0.007) in HBeAg seroclearance subjects were significantly higher than those in the HBeAg persistent group. The multivariable logistic regression model showed that CXCL9 (OR=1.00, 95%CI=1.00-1.01) and CXCL10 (OR=1.02, 95%CI=1.00-1.05) increased the probability of HBeAg seroclearance. Conclusion AST, CXCL9, and CXCL10 were significantly associated with HBeAg seroclearance，the mechanisms should be further explored in studies. Future studies should further investigate the underlying mechanisms.

Objective To explore the evolutionary origin, transmission pattern and population dynamics of hepatitis B virus (HBV) C/D recombinants (CD recombinants) in the Xizang Autonomous Region, so as to provide a theoretical basis for the scientific prevention and control of local hepatitis B. Methods From May 2022 to July 2023, serum samples with double positive for hepatitis B surface antigen (HBsAg) and HBV DNA were enrolled from physical examination population in a hospital of Xizang Autonomous Region, and full-length HBV genomic sequences were acquired. Recombination events were scanned using jpHMM online recombination analysis tool and Simplot software (version 3.5.1). The evolutionary rate and divergence time of HBV were analyzed by Bayesian Markov chain Monte Carlo (MCMC) method implemented in BEAST software. Results HBV CD recombinant genomic sequences were obtained from the 46 study subjects. Evolutionary origin analysis of HBV CD recombinants revealed: the most recent common ancestor (MRCA) of genotype C in C/D1 and C/D2 recombinants (CD1, CD2 recombinants) could be traced back to approximately 1769 [95% highest posterior density (HPD): 1456-1873] and 1763 (95%HPD: 1569-1801), respectively, with average evolutionary rates of approximately 5.23×10^-5 and 4.89×10^-5 nucleotide substitutions per site per year. For genotype D in CD1 and CD2 recombinants, the MRCA were approximately 1887 (95%HPD: 1838-1947) and 1868 (95%HPD: 1808-1925), respectively, with average evolutionary rates of about 3.19×10^-4 and 2.68×10^-4 nucleotide substitutions per site per year. Bayesian Skyline Plot (BSP) analysis indicated that the population size of HBV genotype C in both CD1 and CD2 recombinants exhibited minimal fluctuations. In contrast, the population of HBV genotype D in CD1 recombinants began to increase significantly after 1970, followed by a decline between 2000 and 2010; whereas in CD2 recombinants, genotype D population increased significantly from 1970 to 2000 and decreased from 2010 to 2020. Conclusion The genotype D of HBV CD recombinants in the Xizang Autonomous Region may have originated in Asia in the late 19th century, while genotype C can be traced back to the 18th century, though the transmission routes of genotype C are different. These findings lay a foundation for formulating targeted hepatitis B prevention and control strategies in the region.

Objective To analyze epidemiological characteristics and predict the incidence trend of acute hepatitis B in Tianjin from 2010 to 2024, and provide scientific evidence for control and prevention of acute hepatitis B. Methods We obtained surveillance data of acute hepatitis B in Tianjin from 2010 to 2024, and conducted a descriptive analysis of epidemiological characteristics. Software R 4.4.2 was used to establish an autoregressive integrated moving average (ARIMA) model to predict the monthly incidence of acute hepatitis B in Tianjin. Results A total of 1 875 cases of acute hepatitis B were reported in Tianjin from 2010 to 2024, the average annual incidence rate was 0.87/100 000. The annual reported incidence rates ranged from 0.16/100 000 (in 2024) to 2.52/100 000 (in 2010), showing an overall downward trend (χ²_trend=648.214, P<0.001), without obvious seasonal characteristics. The incidence rate of acute hepatitis B showed no cases in the 0 to <5 years age group, with the majority of cases (64.32%) concentrated among young and middle-aged population aged 30 to 50 years. The incidence rate was higher in males (1.19/100 000) than in females (0.52/100 000) (χ²=273.717，P<0.001). Farmers accounted for the highest proportion of occupation (462 cases, 24.64%). The top three districts of reported incidence rates were Jizhou, Jinghai, and Nankai. A total of 298 serum samples from acute hepatitis B cases collected between 2019 and 2024 underwent genotyping, and 250 successfully genotyped, with genotype C predominating(79.60%, 199/250), followed by genotype B(18.80%，47/250). The optimal model was ARIMA(0,1,1)(1,0,0)_{1 2}, with a root mean square error (RMSE) of 4.03 and a mean absolute error (MAE) of 3.14. Actual values consistently fell within the 95%CI of predicted values. Conclusions The incidence rate of acute hepatitis B in Tianjin Municipality has shown an overall downward trend and has remained at a low level. The ARIMA model shows a good predictive effect on the incidence of acute hepatitis B in Tianjin, and has certain reference value for control and prevention of acute hepatitis B.

Objective To investigate the mechanism of hepatitis B virus DNA polymerase transactivated protein 1 (HBVDNAPTP1) in the apoptosis signaling pathway of monocytes. Methods A full-length eukaryotic expression vector of the HBVDNAPTP1 gene was constructed. Three groups were established: the negative control group, the pCMV-Myc empty vector group, and the HBVDNAPTP1 overexpression group. Following intervention in THP-1 cells, the apoptosis rate and intracellular ultrastructure were examined. Quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence, and Western blot were used to detect the mRNA and protein expression levels of carboxylesterase 1 (CES1) and B-cell lymphoma-2 (Bcl-2). Co-immunoprecipitation was employed to determine the targeted binding relationship between HBVDNAPTP1 and CES1. Cell proliferation was detected by CCK-8 (cell counting Kit-8) assay, and cell apoptosis was analyzed by flow cytometry. Results CCK-8, flow cytometry apoptosis assay, and electron microscopy results showed that, compared with the control and the pCMV-Myc empty vector group, overexpression of HBVDNAPTP1 significantly inhibited the proliferation and promoted the apoptosis of THP-1 cells (P<0.001). Transmission electron microscopy (TEM) further revealed that HBVDNAPTP1 overexpression caused cellular damage and impaired organelle structure. The results of qRT-PCR, Western blot (WB), and immunofluorescence consistently indicated that, compared with the control group, the expression level of the CES1 was significantly upregulated (P<0.001) and the expression of the Bcl-2 gene was significantly downregulated (P<0.01) in the HBVDNAPTP1 overexpression group. Co-immunoprecipitation results confirmed a targeted binding relationship between HBVDNAPTP1 and CES1. Conclusion HBVDNAPTP1 can induce apoptosis of THP-1 cells and may influence the occurrence of hepatitis B by inducing the expression of CES1.

Objective To investigate the effects of astaxanthin on liver function and liver fibrosis in rats with hepatitis B, and to analyze its relationship with the sphingosine kinase 1 (SphK1)/sphingosine 1-phosphate (S1P) pathway. Methods HBV rat models were established, and assigned into HBV group, astaxanthin-low dose (astaxanthin-L) group, astaxanthin-medium dose (astaxanthin-M) group, astaxanthin-high dose (astaxanthin-H) group, and astaxanthin-H+SphK1 activator PMA (astaxanthin-H+PMA) group, with 12 rats in each group. Another 12 rats were taken as control group. The liver function indicators, fibrosis indicators, HBV markers, and inflammatory factor indicators were detected by ELISA. The pathological changes of liver tissue were detected by HE staining. Liver fibrosis was detected by Masson staining. In addition, the protein expression was detected by Western blot. Results In the control group, the hepatocytes of rats were arranged radially, with an orderly structure, and there was no obvious swelling or infiltration of inflammatory cells. In the HBV group, the hepatocytes of rats were randomly arranged, the nucleoli shrank, and there were obvious inflammatory cell infiltration and punctate necrosis. Compared with the control group, the alanine aminotransferase (ALT), aspartate aminotransferase (AST), laminin (LN), hyaluronic acid (HA), procollagen type Ⅲ (PCⅢ), hepatitis B e antigen (HBeAg), hepatitis B surface antigen (HBsAg), interleukin-2 (IL-2), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), Ishak scores, collagen volume fraction, and the expressions of SphK1 and S1P were higher in the HBV group (P<0.05). Compared with the HBV group, the ALT, AST, LN, HA, PCⅢ, HBeAg, HBsAg, IL-2, IFN-γ, TNF-α, Ishak scores, collagen volume fraction, and the expressions of SphK1 and S1P were lower in the astaxanthin-L, M and H groups (P<0.05). Compared with the astaxanthin-H group, the ALT, AST, LN, HA, PCⅢ, HBeAg, HBsAg, IL-2, IFN-γ, TNF-α, Ishak scores, collagen volume fraction, and the expressions of SphK1 and S1P were higher in the astaxanthin-H+PMA group (P<0.05). Conclusion The inhibitory effect of astaxanthin on liver tissue fibrosis and its improvement on liver function in HBV rats may be achieved by inhibiting the SphK1/S1P pathway.

Objective To analyze the epidemiological characteristics and predict the incidence trend of hepatitis E in Tianjin from 2018 to 2025, and explore the association between genotype distribution and epidemiological features, and provide evidence for scientific prevention and control of hepatitis E. Methods Surveillance data of hepatitis E in Tianjin from 2018 to 2025 were collected from the China Information System for Disease Control and Prevention. The epidemiological characteristics of incidence and clustering were analyzed. The autoregressive integrated moving average (ARIMA) seasonal model was used to predict the monthly number of hepatitis E cases in Tianjin. Hepatitis E virus (HEV) genotypes were detected by nested PCR and comprehensively analyzed in combination with demographic and epidemiological characteristics. Results A total of 1 208 hepatitis E cases were reported in Tianjin from 2018 to 2025, with an average annual incidence of 1.06/100 000. The overall incidence showed an increasing trend (χ²_trend=639.200, P<0.001), with a peak from February to April each year. The top three districts with the highest reported incidence were Ninghe District, Nankai District, and Hedong District. Middle-aged and elderly individuals aged 45 to <80 years accounted for 81.71% of the total cases. The number of male cases was higher than that of female cases (2.75∶1). Retires and farmers were the main affected occupations, accounting for 35.02% and 21.52%, respectively. A total of 9 clustering outbreaks were reported, mainly transmitted through close household contact (88.89%). The optimal forecasting model was ARIMA (1,1,1) (1,0,0)₁₂. Among 381 successfully genotyped cases, HEV genotype 4 accounted for 98.43% (375 cases), with HEV 4d being predominant and showing an increasing proportion over the years (χ²_trend=30.984, P<0.001). No statistically significant differences were found in clinical characteristics or infection sources among different subtypes (P>0.05). Conclusions The incidence of hepatitis E in Tianjin shows an overall increasing trend, with high occurrence in males, middle-aged, and elderly populations. Close household contact is the main cause of clustering outbreaks of hepatitis E. HEV genotype 4 is predominant. Targeted prevention and control measures should be implemented for key populations during the periods surrounding the Spring Festival.

Objective To establish a Salmonella detection process combining real-time PCR (qPCR) primary screening and targeted isolation, compare its detection performance with the traditional isolation and culture method in various types of food and related samples, and evaluate its feasibility in food safety risk surveillance. Methods Real-time PCR was applied to verify the specificity of 17 common foodborne pathogens and the inclusivity of 96 Salmonella serotypes. The sensitivity and robustness of the workflow were assessed through matrix-spiking experiments and competitive interference assays with high concentrations of background bacteria, such as Escherichia coli. The optimized workflow was then applied to food safety risk surveillance and compared with the GB 4789.4-2024 national standard method. Results The real-time PCR method exhibited 100% specificity and inclusivity. In the simulated spiking experiments of various food and related samples, the detection sensitivity of real-time PCR reached over 100 CFU (Colony-Forming Unit)/mL, and the results of real-time PCR were consistent with those of isolation and culture. In the simulated interference experiments, high-concentration Escherichia coli contamination in samples led to an increase in the Ct (Cycle threshold) value of Salmonella real-time PCR and affected the results of isolation and culture. In the risk surveillance of 341 samples, the detection rate of the new process (9.38%, 32/341) was significantly higher than that of the national standard method (7.62%, 26/341), and 1 sample was positive by real-time PCR but negative by isolation and culture. Conclusion The Salmonella detection process combining real-time PCR primary screening and targeted isolation established in this study can rapidly and accurately detect Salmonella in food and related samples, compensating for the limitations of the national standard method in terms of speed and throughput. It is recommended as a supplementary non-standard rapid detection method for applications including emergency investigations of foodborne disease outbreaks, rapid screening in food circulation links, and daily detection work in grassroots laboratories.

Objective To analyze the whole-genome characteristics of five Coxsackievirus group A type 4 (CV-A4) strains isolated from hand-foot-mouth disease (HFMD) case specimens in Qinghai Province in 2023-2024, and to explore the characteristics of gene variation and evolution, so as to provide scientific basis for prevention and control of HFMD. Methods Human rhabdomyosarcoma cells (RD) were used to isolate viruses from nucleic acid-positive samples from HFMD cases. The viral RNA was extracted and subjected to whole-genome sequencing of enteroviruses using DNBSEQ-T7 platform. The CV-A4 sequences were aligned and compared for homology using BioAider software (version 1.423). Phylogenetic trees were constructed for the whole-genome sequences, P1, P2, and P3 gene coding regions of CV-A4 isolates and prototype strains using Phylogeny function of MEGA software (version 7.0.14). Five viral isolates for recombination analysis was employed using EV-A prototype strains as reference sequences by SimilarityPlots software. Results Four CV-A4 isolates belonged to sub-genotype C2, of which three were closest to Chinese strain LC707391.1 in 2021, and one isolate closest to Chinese strain MT920660.1 in 2019. One isolate belonged to sub-genotype C5, and was closest to British strain OQ319985.1 in 2020. The five isolates showed the higher nucleotide similarity to the CV-A4 prototype strain, ranging from 84.18% to 84.55%. The gene regions with high nucleotide similarity to the CV-A4 prototype strain are the 5'UTR, P1, VP4, VP2, VP3, VP1, P3, 3A, and 3D, followed by P2, 2A, 2B, 2C, 3B, and 3C. Gene recombination analysis revealed that, the five isolates exhibited high similarity with the CV-A4 prototype strain in the P1 region, while, the five isolates showed high similarity with the five EV-A prototype strains in the 5'UTR region, P2 and P3 regions. Conclusion The study preliminarily revealed the genetic relationships and variations of the VP1 gene of enterovirus CV-A4 in Qinghai Province, identifying sub-genotype C2 as the dominant epidemic strain of CV-A4 in HFMD.

Objective To investigate the epidemic characteristics and VP1 region gene features of Coxsackievirus A10 (CVA10) among hand-foot-mouth disease (HFMD) cases in Shenzhen from 2017 to 2023. Methods Throat swab samples were collected from HFMD cases at sentinel hospitals in Shenzhen from 2017 to 2023. Fluorescent RT-PCR was employed to screen for CVA10 nucleic acid-positive samples, followed by full-length amplification and sequencing. Bioinformatics software, including BioEdit and MEGA 11.0, was used for sequence alignment and phylogenetic analysis. Results From 2017 to 2023, a total of 4 785 clinically diagnosed HFMD cases were reported in Shenzhen, of which 155 were CVA10-positive, accounting for 3.24%, with a male-to-female ratio of 1.63. Patients aged under 2 years accounted for 42.58% (66/155), with the 1-2 year age group having the highest proportion at 28.39% (44/155). CVA10-type HFMD peaked in consultation visits in 2018 and 2021, showing a marked divergence from the gradually diminishing epidemic trend of local EV71-type HFMD during the same period. Phylogenetic analysis revealed that nucleotide homology among the 42 selected CVA10 strains from Shenzhen during 2017-2023 ranged from 91.3% to 100.0%, while amino acid homology ranged from 96.3% to 100.0%. All CVA10 strains in Shenzhen belonged to the C2 genotype; of these, 10 strains were locally circulating strains, 28 strains were phylogenetically closely related to epidemic strains from Zhejiang, Chongqing, Wuhan, Nanchang, Shanghai, Yunnan, and Shandong, and 4 strains were most closely related to the US epidemic strain MT317977-USA-2014. Further comparison between the 2017-2023 circulating CVA10 strains from Shenzhen and CVA10 strains isolated from severe HFMD cases revealed two amino acid mutation sites associated with severity, namely I283V and T284A. Conclusion All CVA10 epidemic strains in Shenzhen from 2017 to 2023 belonged to the C2 subtype. Two amino acid mutation sites related to severity were identified, namely I283V and T284A, both located at the C-terminal of VP1 and related to CVA10 target binding. Although I283V does not directly interact with the receptor, it may indirectly affect the receptor-binding ability by destabilizing the C-terminal of the VP1 protein.

Objective To analyze the epidemiological characteristics of foodborne disease outbreaks caused by Vibrio parahaemolyticus in Hainan Province from 2015 to 2024, and to provide a scientific basis for formulating targeted prevention and control strategies. Methods Based on data retrieved from the National Foodborne Disease Outbreak Surveillance System, foodborne disease outbreak records caused by Vibrio parahaemolyticus in Hainan Province from 2015 to 2024 were collected and compiled. Descriptive epidemiological methods were used to analyze characteristics such as time, region, population, setting, pathogen, and risk factors. Results From 2015 to 2024, a total of 100 outbreaks of foodborne illness caused by Vibrio parahaemolyticus were reported in Hainan Province, involving 1 026 cases, 109 hospitalizations, and no fatalities, with a total of 14 001 exposed individuals. Outbreaks occurred throughout the year, with reports in all months except April. The third quarter was the peak period, accounting for 58 outbreaks (58.00%) and 452 cases (44.05%); The attack rate for this quarter was 9.78%, significantly higher than the average attack rate of 6.12% across the first, second, and fourth quarters (χ²=319.34, P<0.001). August recorded the highest number of cases, accounting for 23.00% of the total. Regarding regional distribution, Sanya City (42 outbreaks), Haikou City (38 outbreaks), and Danzhou City (8 outbreaks) reported the highest numbers. Outbreak locations were primarily restaurants (57.00%), followed by construction site canteens (9.00%) and school canteens (7.00%). Serotype O3:K6 was the predominant serotype, solely responsible for 17.00% of outbreaks and involved in 21.00% of outbreaks either alone or in combination with other serotypes, other major serotypes included O4:K8 and O3:K4. High-risk food items were primarily aquatic products (29.00%), followed by mixed food products (14.00%) and meat and meat products (12.00%). The main contributing factors were cross-contamination (23.00%), improper processing practices (16.00%), and improper storage (13.00%). Conclusions Outbreaks of foodborne disease caused by Vibrio parahaemolyticus in Hainan Province exhibit a distinct seasonal peak, with the highest risk occurring in the third quarter. Aquatic products are the primary high-risk food category, restaurants are the main sites of outbreaks, and cross-contamination is a key risk factor. It is recommended to strengthen supervision during peak seasons, for high-risk food categories, and at key locations; enhance monitoring of aquatic products and food safety education; and improve operational standards among food service practitioners to reduce the risk of Vibrio parahaemolyticus-related foodborne disease outbreaks.

Objective To analyze the epidemiological characteristics of Vibrio parahaemolyticus (VP) in Changzhou, Jiangsu Province from 2015 to 2022, and to investigate bacteriological characteristics and expression of virulence‑related genes in VP strains isolated from seawater and freshwater, so as to provide a scientific basis for the study on adaptive evolution of VP in freshwater environments and the prevention, control and risk warning of local foodborne diseases. Methods VP strains were isolated from food risk monitoring and food poisoning cases in Changzhou Jiangsu Province from 2015 to 2022. Halophilicity was detected by culturing in LB medium with different NaCl concentrations (0%, 0.5%, 1.0%, 2.0%, 3.0%, 5.0%), and optical density (OD) values were measured to draw growth curves every 2 hours. Virulence genes including thermolabile hemolysin gene (tlh), toxin regulatory gene (toxR) and type Ⅲ secretion system-related gene (VPA0450) were detected by real‑time fluorescent quantitative PCR. Cytotoxicity was determined using human colon carcinoma cell line (Caco‑2) infection model combined with lactate dehydrogenase (LDH) assay. Results A total of 48 seawater‑derived VP strains and 46 freshwater‑derived VP strains were collected. All seawater‑derived VP strains (100.0%) carried toxR gene, while 76.0% of freshwater‑derived VP strains carried toxR gene. In growth assays, freshwater‑derived VP strains grew significantly faster than seawater‑derived strains (0% NaCl, P=0.002 1; 0.5% NaCl, P=0.009 6; 1.0% NaCl, P=0.045 0). In contrast, seawater‑derived VP strains exhibited superior growth at 2.0% (P=0.047 0) and 3.0% NaCl (P=0.046 0). At 0%, 0.5% and 1.0% NaCl, the cytotoxicity of freshwater‑derived VP was approximately 20.0% higher than that of seawater‑derived VP. Conclusion There are significant differences in halophilic growth characteristics, virulence gene carriage and cytotoxicity between seawater‑derived and freshwater‑derived VP strains in Changzhou. Freshwater‑derived strains grow faster and exhibit higher cytotoxicity in low‑salt environments (0%-1.0% NaCl), with a significantly higher carriage rate of VPA0450 gene; while seawater‑derived strains grow better at 2.0%-3.0% NaCl. These findings indicate that Vibrio parahaemolyticus has undergone adaptive evolution to freshwater environments, with enhanced viability and virulence under low‑salt conditions, which can provide a scientific basis for the prevention, control and risk warning of freshwater product‑related foodborne diseases in inland areas.

Objective This study aimed to elucidate the role of caseinolytic protease P (ClpP) in the physiological functions and virulence of Burkholderia pseudomallei (Bp), and to provide a new experimental basis for understanding the infection mechanism of this pathogen. Methods This study used the auxotrophic strain (HNBP001) as the starting strain, and successfully constructed the clpP gene deletion mutant (ΔclpP) and the clpP gene complementation strain (ΔclpP::clpP) using homologous recombination technology. This study systematically elucidated the multifaceted regulatory roles of the clpP gene in bacterial growth, antibiotic resistance and virulence, through growth curve analysis, antimicrobial susceptibility testing, biofilm formation assessment, and cell infection experiments. Results This study successfully constructed and validated the ΔclpP and ΔclpP::clpP strains. The deletion of the clpP gene led to significant alterations in key pathogenic phenotypes of the bacteria. Deletion of the clpP gene resulted in a significant alteration of key pathogenic phenotypes of the bacterium, and the biofilm formation ability of ΔclpP was attenuated compared with HNBP001 (F=5.216, P<0.05). The swimming motility assay showed that the swimming area of ΔclpP was smaller than that of HNBP001 and ΔclpP::clpP at all time points, and the differences began to be observed since 48 h (F=9.393, P<0.05). In the host cell infection experiment, cell viability increased from about 55% (HNBP001) to about 70% (ΔclpP). Furthermore, the susceptibility of ΔclpP to multiple antibiotics increased significantly, with the minimum inhibitory concentration (MIC) values for ceftazidime, ceftriaxone, cefotaxime, and amikacin all reduced 50% compared to the baseline levels. Conclusion This study systematically validated the regulatory role of clpP on multiple critical phenotypes of Bp, including motility, virulence, and antibiotic resistance. The deletion of clpP simultaneously attenuated bacterial virulence and enhanced its sensitivity to antibiotics. This "dual-effect" characteristic highlights its unique advantage as a potential drug target. This finding suggests that clpP could serve as a crucial target for developing novel antimicrobial strategies, providing a new research direction for the prevention and control of Bp infections.

Objective To analyze the cyclical characteristics of influenza incidence in China, compare the predictive performance of machine learning models with traditional time series models, and provide references for relevant authorities in formulating corresponding prevention and control policies. Methods Monthly data on the incidence of influenza in China from March 2009 to September 2025 were collected. The seasonal characteristics of the influenza incidence in China were analyzed using the Census X-13 seasonal adjustment method, and the cyclical periodicity characteristics of the incidence were analyzed using the HP (Hodrick-Prescott) filter method. Using the logarithmically transformed values of the incidence numbers from March 2009 to March 2023 as the training set and the logarithmic conversion values of China's influenza incidence from April 2023 to September 2025 as the test set. Machine learning models, including the LSTM model and the XGBoost model, were constructed and compared with traditional time series models, including the SARIMA model and the Holt-Winters model. The model's fitting and prediction performance were assessed by four metrics: coefficient of determination (R²), mean absolute error (MAE), root mean square error (RMSE), and mean absolute percentage error (MAPE). Results From 2009 to 2025, the incidence of influenza in China presented a distinct seasonality and periodicity. The seasonal factor curve showed a clear unimodal pattern, with the summer being the low-incidence period and the winter the high-incidence period. There were approximately seven cycles, with an average duration of 24 months. The fluctuation range and length of each phase are variable. Comparing the fitting metrics of the four prediction models, the XGBoost machine learning model shows the best predictive and fitting performance, followed by the LSTM model, then the Holt-Winters model, with the SARIMA model being the worst. Forecasting based on the XGBoost model for the next five years suggests that there is still a risk of a sharp rise in the incidence. Conclusion From 2009 to 2025, the incidence of influenza in China demonstrated a long-term upward trend, characterized by a seasonal characteristic of being higher in winter and lower in summer. The fluctuation amplitude and cycle length of the cycle are unstable. The XGBoost machine learning model exhibited high predictive accuracy for time series data with seasonality and periodicity, providing a valuable reference for the influenza prevention and control efforts of relevant departments.

Objective To investigate the role of epithelial-mesenchymal transition (EMT)-related genes in immune response and EMT in patients with female genital tuberculosis (FGTB), and to provide reference for early diagnosis and the development of individualized treatment strategies for FGTB. Methods A total of 30 FGTB patients treated at Guangzhou Chest Hospital from June 2022 to June 2023 were selected, along with 32 healthy individuals who voluntarily provided peripheral blood at the same hospital during the same period as the healthy control group. A random subset of samples (5 FGTB patients and 7 controls) was subjected to RNA sequencing (RNA-seq) analysis. The remaining independent samples (25 FGTB patients and 25 controls) were used for qPCR validation and ROC analysis to evaluate the diagnostic efficacy of candidate genes. Differentially expressed genes and their associated biological pathways were identified through comprehensive bioinformatics analysis. Results Through differential expression analysis of 5 FGTB patients and 7 healthy controls, we found significant expression differences in a total of 16 194 genes, among which 767 genes met the criteria of |log2FC|>1 and P<0.05. In addition, 257 DEGs intersected with a public EMT gene list. Functional enrichment analysis showed that these genes play important roles in muscle cell differentiation, negative regulation of the immune process, and cell chemotaxis. ROC analysis showed that the AUC values of 8 hub genes exceeded 0.8, indicating potential diagnostic value. The qRT-PCR validation results further confirmed that the expression differences of MMP9 (P<0.05), CXCL8 (P<0.05), and CD274 (P<0.01) were statistically significant in the validation cohort. Immune infiltration analysis results showed that the infiltration of B cells and regulatory T cells was upregulated in the FGTB group, while neutrophils were significantly downregulated, which may contribute to the immune escape and pathological progression of FGTB. Conclusion This study enhances the understanding of the molecular mechanisms and immune microenvironment of FGTB, suggesting that MMP9, CXCL8, and CD274 may serve as biomarkers, providing a foundation for the early diagnosis and development of personalized treatment strategies for FGTB.

Objective To investigate the effects of age, period, and birth cohort on the risk of pulmonary tuberculosis (PTB) incidence, and to provide scientific evidence for the formulation of PTB prevention and control strategies and the rational allocation of health resources in Hainan Province, China. Methods Data were obtained from the Infectious Disease Reporting and Information Management System of the China Disease Prevention and Control Information System. An age-period-cohort (APC) model was applied to analyze PTB reported incidence data in Hainan Province from 2000 to 2024 and in its cities and counties from 2005 to 2024. The effects of age, period, and birth cohort on temporal trends in PTB reported incidence were evaluated. Results From 2000 to 2024, the reported incidence of PTB in Hainan Province and its cities and counties showed an overall continuous declining trend. Age, period, and birth cohort effects jointly influenced the PTB epidemic at different dimensions (χ²_age=317.81, χ²_period=338.59, χ²_cohort=126.61; all P<0.05). The age effect indicated that young adults (20-<30 years) and older adults (≥60 years) were the main high-risk populations. The period effect showed that PTB reported incidence peaked during 2005-2009 (RR=1.38, 95%CI: 1.28-1.49), followed by a declining or relatively stable trend since 2010-2014 onward, with most cities and counties exhibiting consistent period-related patterns. The cohort effect further demonstrated that earlier birth cohorts experienced higher PTB risk after entering middle and older age, whereas PTB reported incidence showed an overall declining trend across the same age groups as birth year became more recent. Conclusion From 2000 to 2024, the reported incidence of PTB in Hainan Province and its cities and counties exhibited an overall downward trend. Age, period, and birth cohort factors jointly influenced the PTB epidemic, with young adults and older adults identified as key high-risk populations. Stratified and precision-oriented tuberculosis prevention and control strategies should be further promoted to reduce the regional disease burden.

Objective To analyze of the investigation and emergency response to the first local chikungunya fever cluster in city C, and provide reference for the prevention and control of chikungunya fever in the future. Methods Field epidemiological investigations were carried out on an outbreak of chikungunya fever in S community of G District in C city from August 1, 2025 to September 12, 2025, along with active case investigation, case search and mosquito vector emergency monitoring. Expert consultations were conducted to explore risk assessment and investigation, prevention, and control strategies for local cases. Results A total of 4 local cases were identified, main clinical manifestations with fever, rash, and arthralgia. The time from symptom onset to medical consultation/reporting ranged from one to two days, with a median interval from the onset to diagnosis of two days. All cases were mild and recovered after approximately one week of hospitalization under mosquito-proof isolation treatment. Transmission chain investigation revealed that all four cases had a common exposure source. The initially estimated exposure period was primarily in the afternoon to evening, with risk factors including dog walking, failure to use repellents, and wearing short-sleeved shirts and shorts. No secondary cases were detected among cohabitants or in active case searches in high-risk areas and health monitoring. All four cases tested positive for CHIKV RNA, with genetic sequencing revealing that all were ECSA (East/Central/South African type) genotype. Initial Aedes mosquito surveillance showed a Breteau index (BI) of 6.52 and a mosquito tent trap index of 0 on the first day. After vector control measures, both indices met the standard thresholds of BI: 1.35 and trap index: 0.67 mosquitoes/(tent•hour) by day 3. Conclusion Comprehensive prevention and control measures such as case search and management, vector surveillance and control in high-risk areas and sites, health monitoring, and public health education can effectively contain the chikungunya cluster. The locally developed chikungunya fever response toolkit and experience, based on the investigation and handling of this cluster, provide a reference for other regions in responding to local chikungunya fever cluster/outbreaks.

Objective To analyze the spatiotemporal distribution characteristics of the chikungunya fever epidemic in Nanning in 2025, clarify the epidemic aggregation rules and diffusion trajectory, and provide a scientific basis for formulating precise prevention and control strategies. Methods Data on local and imported chikungunya fever cases and population data of each subdistrict (town) in Nanning in 2025 were collected, a database was established, and statistical analyses were conducted. QGIS 3.36.0 software was used to conduct global and local spatial autocorrelation analysis, combined with SaTScan 10.3.3 software for spatiotemporal scan clustering analysis, to identify the spatiotemporal aggregation areas and characteristics of the epidemic. Results A total of 946 chikungunya fever cases were reported in Nanning in 2025, with an incidence rate of 10.82 per 100 000 population. Among them, there were 893 locally acquired cases (94.40%) and 53 imported cases (5.60%), mainly from Guangdong Province (52 cases, 98.11%). The epidemic peaked from August to October, accounting for 94.82% of the annual cases. Cases were reported in 61 of the city's 129 subdistricts (towns), accounting for 46.51%. Among them, imported cases were predominantly distributed in townships (62.26%), while locally acquired cases were mainly concentrated in urban subdistricts (82.08%). The overall male-to-female ratio of the cases was 1.05∶1. The median age of imported cases was lower than that of locally acquired cases. Imported cases were predominantly among students/preschool children, workers, and commercial service workers, whereas locally acquired cases were mainly concentrated among homemakers and the unemployed, students/preschool children, and retirees.Spatial autocorrelation analysis revealed that the global Moran's I values from August to December were consistently greater than 0 (P<0.05), reaching a peak of 0.51 in October. Local spatial autocorrelation analysis detected 7 high-high clusters in August, 21 in September,24 in October, 17 in November, and 3 in December. A total of 7 aggregation areas were detected by spatiotemporal scanning (P<0.01), and the initial core aggregation area was Jianzheng Sub-district (RR=62.7, LLR=279.18). Conclusion The 2025 chikungunya fever epidemic in Nanning exhibited significant spatiotemporal aggregation, with a transmission trajectory characterized by the pattern of "single-point outbreak in the central urban area → peripheral diffusion → citywide epidemic in the main urban area → gradual decline". It is recommended that spatial analysis techniques be routinely applied to infectious disease "surveillance and early warning, and targeted prevention and control measures be implemented in high-risk areas.

Objective To retrospectively analyze the clinical characteristics and magnetic resonance imaging (MRI) findings of cerebral paragonimiasis in Yunnan Province, aiming to improve clinicians' understanding and diagnostic accuracy of this rare but severe parasitic disease of the central nervous system. Methods A retrospective study was conducted on patients with confirmed or clinically suspected of paragonimiasis at the Third People's Hospital of Kunming from September 2019 to September 2025. Patients diagnosed with cerebral paragonimiasis were selected as the research objects. The general data, laboratory examinations, and MRI findings were collected and analyzed. Results A total of 109 patients with paragonimiasis were enrolled, among whom 11 patients (10.1%) were diagnosed with cerebral paragonimiasis, comprised 72.7% males and 27.3% females, with age of 12.0 (8.0, 33.0) years. Pediatric patients accounted for 54.5%, and adults for 45.5%. All pediatric cases originated from Zhaotong City, while most adult cases were from Xishuangbanna Prefecture. And 90.9% of patients had elevated peripheral blood eosinophil counts and percentages, and all exhibited a decreased serum albumin/globulin ratio. Brain MRI findings revealed 90.9% of cases had unilateral hemispheric involvement, and 63.6% were multiple lesions. All patients demonstrated patchy low T₁WI and high T₂WI signal intensity. Among them, 72.7% exhibited a hypointense "tunnel sign", composed of a tunnel cavity and wall, with the tunnel wall showing significant enhancement on contrast-enhanced scans. And 36.4% of patients showed subacute intralesional hemorrhage. And 90.9% of the cases had pulmonary lesions, 36.4% had pleural effusion, and 36.4% had liver abnormalities. Conclusion Cerebral paragonimiasis is characterized on brain MRI by the "tunnel sign" accompanied by perilesional brain parenchymal edema, often with intralesional hemorrhage. Elevated peripheral blood eosinophil levels and changes in the serum albumin/globulin ratio may aid in differential diagnosis.

Objective To establish a rapid and efficient liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for screening and quantitative analysis of 12 target compounds in biological samples from patients suspected of anticoagulant rodenticide poisoning. Methods A total of 100 μL serum or urine samples were directly extracted using a mixture of methanol and acetonitrile. The separation was performed on an Atlantis T3 column (150 mm×2.1 mm, 3 μm) with a gradient elution using ammonium acetate solution (5 mmol/L) and acetonitrile. Mass spectrometry analysis was conducted in the negative electrospray ionization mode with multiple reaction monitoring (MRM). The method was comprehensively validated for linearity, sensitivity, accuracy, and precision, and it was applied to the clinical detection of a critically ill patient in late pregnancy. Results Method validation demonstrated good linearity (r≥0.997) for all 12 anticoagulant rodenticides within a range of 0-400 μg/L. The limits of detection (LOD) and quantification (LOQ) were 0.1-0.5 μg/L and 0.3-1.7 μg/L, respectively. Spiked recoveries for blood and urine samples were 79%-129% and 67%-118%, respectively, with relative standard deviations (RSDs) below 11%, indicating satisfactory accuracy and precision. When applied to clinical cases, the method rapidly detected a concentration of warfarin as high as 1 664 μg/L in the mother's serum and 360 μg/L in the newborn's serum. The maternal-neonatal serum concentration ratio and their respective blood-urine distribution ratios were consistent with the pharmacokinetic characteristics of warfarin. Conclusion The developed LC-MS/MS method features minimal sample volume, simple pretreatment, fast analysis, high sensitivity, and good accuracy, making it suitable for emergency toxicological screening. The detection of high warfarin concentrations in both maternal and neonatal serum, alongside clinical symptoms and coagulation tests, confirmed warfarin poisoning. This method proved effective for rapid diagnosis and therapeutic monitoring, providing reliable technical support for clinical management and emergency responses to anticoagulant rodenticide poisoning.

Objective To analyze the distribution characteristics of virulence genes in Bacillus cereus isolates from different types of food in Sichuan Province, providing a scientific basis for the prevention and control of food poisoning caused by B. cereus. Methods Whole genome sequencing (WGS) was performed on 791 strains of B. cereus isolated from routine food monitoring in Sichuan Province from 2017 to 2024 to analyze the distribution characteristics of their virulence genes. Detection of major virulence genes was conducted on 458 B. cereus strains isolated during 2022-2024. Results Among the 333 B. cereus strains isolated from 2017 to 2021, each carried at least four virulence genes, with an average of 6.90 virulence genes per strain. The carriage rates of virulence genes nhe (nheA, nheB, nheC), hblA, hblC, hblD, inhA, BAS3109, cytK, and the ces gene cluster (cesA, cesB, cesC, cesD, cesH, cesP, and cesT) were 100.0%(333/333)、53.5%(178/333)、54.1%(180/333)、54.1%(180/333)、100.0%(333/333)、95.2%(317/333)、58.0%(193/333), and 4.8%(16/333), respectively. The virulence gene carriage profiles varied slightly across different years. Instant cereal products had the highest average number of virulence genes per sample (7.64), while vegetables and their products had the lowest (6.11). Significant differences were observed in the number of virulence genes carried among the six food categories. The hemolytic hbl gene presented the highest carriage rate (72.7%, 8/11)in instant cereal products and the lowest (28.1%, 9/32) in local specialty foods, including ice jelly and cold rice jelly. The cytK gene had the highest carriage rate in Chinese cold dishes. The carriage rate of the ces gene cluster was the highest in local specialty foods (ice jelly and cold rice jelly) and the lowest in vegetables and their products. The carriage rate of nheB during 2022-2024 (85.2%, 390/458) decreased significantly compared to that during 2017-2021 (100.0%) (P<0.001). Conclusion Diarrheic virulence genes of B. cereus are widely distributed in food in Sichuan Province, whereas the carriage rate of emetic virulence genes is relatively low. The high prevalence of B. cereus virulence genes in instant cereal products poses a potential threat to consumers. Continued intensification of monitoring for B. cereus virulence genes is warranted to provide a scientific basis for preventing and controlling food poisoning caused by this bacterium.

Objective To investigate the artificial radioactivity levels in seafood from the coastal waters of eastern and western Hainan Province, and to assess the annual committed effective dose to the population attributable to seafood consumption. Methods From April to October 2024, 16 seafood samples of five types were collected from the coastal waters of eastern and western Hainan Province. The activity concentrations of artificial radionuclides were measured using a high-purity germanium γ spectrometer, a low-background α/β counter, and an ultra-low-background liquid scintillation spectrometer. Combined with residents' seafood intake data, the population's intake and the resulting annual committed effective dose were estimated. Results All 16 seafood samples tested positive for tritium (³H) and carbon-14 (¹⁴C); ¹³⁷Cs was detected in 4 marine fish and 1 seaweed sample, and ⁹⁰Sr was detected in 1 marine fish, 2 shrimp, and 2 oyster samples, while the activity concentrations of ⁶⁰Co, ¹³⁴Cs, and ¹³¹I were all below the minimum detectable level (<MDL). The activity concentration ranges were <MDL-0.044 Bq/kg (¹³⁷Cs), <MDL-0.010 Bq/kg (⁹⁰Sr), 0.017-0.516 Bq/kg (³H), and 2.33-26.19 Bq/kg (¹⁴C). No statistically significant differences in ³H and ¹⁴C activity concentrations were found between the eastern and western coastal waters or among different seafood categories (P>0.05). The estimated intake from seafood consumption was 0.99 Bq (³H), 0.25 Bq (¹⁴C), 5.08 Bq (¹³⁷Cs), and 242.84 Bq (⁹⁰Sr), yielding an annual committed effective dose of 1.61×10⁻⁴ mSv/a. Conclusion No radiation contamination attributable to the discharge of nuclear-contaminated water from Japan's Fukushima nuclear plant or to the operation of the Changjiang Nuclear Power Plant was observed in the nearshore waters of Hainan Province. The current levels of artificial radionuclides in seafood from the nearshore waters of Hainan Province remain at background levels, and the effective dose burden to the population from seafood consumption is at a low level.

Objective This study aimed to investigate distribution of Biomphalaria straminea, identify key environmental drivers in the Dasha River, Shenzhen, and evaluate the transmission risk of imported schistosomiasis mansoni. Methods In 2024, surveillance sites were established across Dasha River of Shenzhen City. Snail surveys were conducted using the manual collection method, with concurrent recording of environmental parameters. Snail species identification was performed using both morphological and molecular (DNA barcoding) methods. The current spatial-temporal distribution pattern and evolution trend of B. straminea was compared with historical data from 2012. Results The survey in 2024 revealed a significant spatial redistribution of B. straminea in the Dasha River. Molecular identification confirmed a stable colonization population (based on rDNA sequence alignment, similarity to the reference sequence of Biomphalaria straminea was 99.89%) only at Beihuan Shahe Overpass section (midstream), with a density of 6.4 snails/m². The water at this site was weakly alkaline (pH 7.6), with a phosphate concentration of 0.13 mg/L and slow water flow (1.15 m³/s). In contrast, the population of the snails at the historically high-density site at Liuxian Avenue North section (upstream) and the low-density site at Shennan Shahe Overpass section (midstream) had been completely extirpated. Comparative analysis of water quality parameters indicated that, the phosphate concentration at the colonized site (Beihuan Shahe Overpass section, 0.13 mg/L) was higher than the maximum value (0.12 mg/L) at snail-free sites, and the flow velocity (1.15 m³/s) was significantly lower than the median (12.70 m³/s) at snail-free sites. Conclusion Riverbank ecological modifications by improving local habitat conditions, are likely a key driver for the population re-establishment in the midstream and the overall redistribution within the basin. Considering the frequent cross-border population movements in Shenzhen, there exists a tangible risk of local transmission of imported schistosomiasis mansoni. This highlights the necessity of establishing an integrated early-warning system that combines environmental DNA (eDNA) surveillance, health screening of cross-border populations and multi-sectoral information sharing.

Dabie bandavirus (DBV), first identified in China, is a novel Bandavirus within the Phenuiviridae family. Infection can cause severe fever with thrombocytopenia syndrome (SFTS), which typically presents with fever, fatigue, chills, myalgia, and, death due to multi-organ failure in severe cases. A 66-year-old woman who was admitted with fever, fatigue, and myalgia after working in a mountainous area. Laboratory tests showed that white blood cells and platelets were significantly decreased, inflammatory indicators were significantly increased, myocardial enzymes, myoglobin, liver and kidney function indicators were significantly increased; DBV-RNA was positive. Based on clinical manifestations and laboratory findings, she was diagnosed with DBV infection complicated by rhabdomyolysis, acute hepatic and renal insufficiency, hypoalbuminemia, and electrolyte disturbances. After antiviral therapy, fluid resuscitation, nutritional support, and symptomatic management, the patient's condition gradually improved and was discharged. This case suggests that DBV infection may not only produce classic SFTS, but also trigger rhabdomyolysis and multi-organ injury; Clinical attention should be paid to early identification and timely intervention to reduce the incidence and mortality of severe SFTS.