ObjectiveTo explore the potential mechanism of Shenqi Jianxin Formula （参芪健心方） in the treatment of chronic heart failure （CHF） from the perspective of regulating mitochondrial autophagy via the PTEN-induced kinase 1 （PINK1）/E3 ubiquitin ligase （Parkin） pathway. MethodsMale SD rats were subjected to abdominal aortic constriction to establish the CHF model. Twenty-four successfully modeled rats were randomly divided into the model group， sacubitril/valsartan group， and low- and high-dose Shenqi Jianxin Formula groups， with 6 rats in each group. Six other rats were set as the sham surgery group， which were only separated the abdominal aorta and then closed the abdomen. Rats in the low-dose and high-dose Shenqi Jianxin Formula groups were given intragastric administration of Shenqi Jianxin Formula suspension at doses of 4.41 g/（kg·d） and 17.64 g/（kg·d）， respectively； the sacubitril/valsartan group received intragastric administration of sacubitril/valsartan sodium tablet suspension at 10 mg/（kg·d）； the sham surgery group and the model group were given normal saline at 10 ml/（kg·d） via intragastric gavage. The intervention lasted for 4 consecutive weeks. Cardiac function indices including left ventricular ejection fraction （LVEF） and left ventricular fractional shortening （LVFS） were detected， and serum brain natriuretic peptide （BNP） content was measured. HE staining and Masson staining were used to observe myocardial histopathological changes. Transmission electron microscopy was employed to examine the ultrastructure of cardiac tissues. Quantitative real-time polymerase chain reaction （Rt-qPCR） was performed to determine the mRNA expressions of PINK1/Parkin pathway-related factors and autophagy-associated proteins including Beclin-1， p62， and microtubule-associated protein 1 light chain 3 （LC3） in myocardial tissues. ResultsCompared with the sham surgery group， the model group showed significant decreases in LVEF and LVFS levels， an increase in serum BNP content， down-regulated mRNA and protein expressions of PINK1， Parkin and Beclin-1 in cardiac tissues， up-regulated mRNA and protein expressions of p62， as well as significant reductions in LC3B mRNA expression， phosphorylated PTEN-induced kinase 1 （p-PINK1） and phosphorylated E3 ubiquitin ligase （p-Parkin） protein levels， and the ratio of microtubule-associated protein 1 light chain 3-Ⅱ to microtubule-associated protein 1 light chain 3-Ⅰ （LC3Ⅱ/LC3Ⅰ） （P＜0.05）. Pathological results revealed obvious myocardial cell edema， necrosis and degeneration， increased disorder of myocardial fiber arrangement， extensive inflammatory cell infiltration， moderate to severe mitochondrial swelling， a few mitochondrial vacuolar changes， and no obvious autophagy in the field of vision in the model group. Compared with the model group， all the above indicators were significantly improved in the high-dose Shenqi Jianxin Formula group and the sacubitril/valsartan group （P＜0.05）. Moreover， the improvement of each index in the high-dose Shenqi Jianxin Formula group was superior to that in the low-dose group （P＜0.05）. In the high-dose Shenqi Jianxin Formula group， myocardial myofibrils were arranged regularly with orderly orientation， the striated structure was clear， and necrotic cells significantly reduced. ConclusionShenqi Jianxin Formula can activate the PINK1/Parkin signaling pathway in myocardial tissues， enhance mitochondrial autophagy， and clear dysfunctional mitochondria， thereby improving cardiac function and delaying the progression of CHF.

ObjectiveTo evaluate the therapeutic effect of Huazhuo SanJie Chubi presciption （HSCD） on chronic gouty arthritis （CGA） rats with low-grade inflammation and to explore the underlying mechanism with a focus on macrophage polarization. MethodsThe 41 male 6-week-old SD rats were randomly allocated， using the random number table， to a normal group （n=8） and a model group （n =33）. CGA with low-grade inflammation was induced in the model group by daily gavage of potassium oxonate （250 mg·kg^-1·d^-1） and hypoxanthine （300 mg·kg^-1·d^-1）， combined with intra-articular injection of a monosodium urate （MSU） crystal suspension （50 μL， 25 g·L^-¹） into the left ankle twice weekly. After 4 weeks of modeling， 3 rats were randomly selected from each group for model validation. The remaining successfully modeled rats were randomly divided into a model group， an HSCD group （10.35 g·kg^-1·d^-1， gavage once daily）， an M1 polarization agonist group （L-methionine sulfoximine， 300 mg·kg^-1， subcutaneous injection every other day）， an M1 polarization agonist + HSCD group， an M2 polarization inhibitor group （PD0325901， 10 mg·kg^-1·d^-1， gavage once daily）， and M2 polarization inhibitor + HSCD group. The corresponding drug or drug combination was administered according to group assignment， whereas rats in the normal and model groups received 0.5% carboxymethyl cellulose sodium （CMC-Na） vehicle （10.35 g·kg^-1·d^-1， gavage once daily）. All interventions were continued for four weeks. During the intervention period， except for the normal group， potassium oxonate （250 mg·kg⁻¹） and hypoxanthine （300 mg·kg^-1） were co-administered by gavage every other day to maintain the model. At the end of treatment， serum uric acid （SUA）， ankle joint diameter and joint swelling index were measured. The levels of high-sensitivity C-reactive protein （hs-CRP）， interleukin-1β （IL-1β）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， chemokine C-C motif ligand 2 （CCL2）， S100 calcium-binding protein A8/A9 （S100A8/A9）， interleukin-10 （IL-10） and arginase-1 （Arg-1） in serum and joint fluid were determined by enzyme-linked immunosorbent assay （ELISA）. High-frequency ultrasound was used to assess MSU deposition in the ankle joint. Hematoxylin-eosin （HE） staining was performed to evaluate synovial histopathological changes. Quantitative Real-time PCR and immunofluorescence were used to detect the mRNA and protein expression of the M1 macrophage polarization markers inducible nitric oxide synthase （iNOS） and the M2 macrophage polarization marker scavenger receptor cysteine-rich type 1 protein M130 （CD163） in synovial tissue. ResultsCompared with the normal group， the model group showed significantly elevated SUA level and joint swelling index， and increased levels of pro-inflammatory cytokines， CCL2， and S100A8/A9 in both serum and joint fluid （P<0.05）， accompanied by MSU deposition and synovial inflammation in the ankle joint. The mRNA and protein expression levels of macrophage polarization M1/M2 markers iNOS and CD163 in synovial tissues were also significantly up-regulated （P<0.05）. Compared with model group， rats in HSCD group had significantly lower SUA levels， attenuated joint swelling， reduced serum levels of pro-inflammatory cytokines， and decreased levels of CCL2 and S100A8/A9 in both serum and joint fluid， accompanied with alleviated MSU deposition and synovial inflammation （P<0.05）. HSCD markedly downregulated the mRNA and protein expression of M1 marker iNOS （P<0.05）， whereas it had no significant effect on the expression of M2 marker CD163. Compared with the M1 polarization agonist group， the M1 polarization agonist + HSCD group showed significantly reduced joint swelling， lower serum levels of pro-inflammatory cytokines， and decreased levels of CCL2 and S100A8/A9 in joint fluid （P<0.05）. In addition， synovial inflammatory cell infiltration and angiogenesis were attenuated， and iNOS mRNA and protein expression levels were significantly reduced （P<0.05）. Compared with the M2 polarization inhibitor group， the M2 polarization inhibitor + HSCD group exhibited reduced joint swelling， decreased levels of CCL2 and S100A8/A9 in joint fluid and ameliorated synovial inflammation （P<0.05）， whereas the levels of anti-inflammatory mediators （IL-10， Arg-1） and CD163 mRNA and protein expression were not significantly increased. ConclusionHSCD alleviates low-grade inflammation in CGA rats， at least in part， by inhibiting macrophage polarization toward the M1 phenotype.

ObjectiveThis paper aims to observe the effect of Huazhuo Sanjie Chubi prescription （HSCD） on the gouty bone erosion model rats and investigate its action mechanism. MethodsThirty-six two-month-old male SD rats were randomly divided into the blank group with nine rats and the modeling group with 27 rats. The rats in the modeling group were administered hypoxanthine solution at 300 mg·kg^-1·d^-1 and potassium oxonate solution at 250 mg·kg^-1·d^-1， combined with intra-articular injection of 200 μL monosodium urate （MSU） crystal suspension at 25 g·L^-1 into the right ankle joint （joint injection once every three days）， so as to induce the gouty bone erosion model. After four weeks of modeling， three rats were selected from these two groups to validate the model. The modeled 24 rats were randomly divided into the model group， HSCD group （10.35 g·kg^-1·d^-1）， allopurinol group （20 mg·kg^-1·d^-1）， and inhibitor group （LY294002， 10 mg·kg^-1·d^-1）， with six rats per group. Except for the blank group， rats in all other groups continued to receive hypoxanthine solution at 300 mg·kg^-1 and potassium oxonate solution at 250 mg·kg^-1 via gavage concurrently with administration to maintain modeling intervention. The rats in the HSCD group and allopurinol group received administration by gavage at the above doses. The rats in the inhibitor group received an intraperitoneal injection at the above dose. The rats in the blank group and model group received saline （10.35 g·kg^-1·d^-1） by gavage for four consecutive weeks. After administration， ankle joint swelling of the rats in all groups was observed， and the diameters were measured. Bone volume fraction （BV/TV） and bone surface area to bone volume （BS/BV） were observed and quantitatively analyzed by Micro-CT. Histopathological changes in the ankle joint were observed by hematoxylin-eosin （HE） staining and safranin O-fast green staining. The uric acid in the rats' serum was determined by enzyme colorimetry. The levels of inflammatory factors， including tumor necrosis factor-α （TNF-α）， interleukin （IL）-1β， and IL-6 were measured by enzyme-linked immunosorbent assay （ELISA）. The protein expressions of receptor activator of nuclear factor-κB ligand （RANKL） and phosphorylated （p）-phosphatidylinositol-3-kinase （PI3K） in ankle joint tissues of rats were detected by immunofluorescence staining. The mRNA levels of the proteins related to the bone erosion， including RANKL， tartrate-resistant acid phosphatase （TRAP）， cathepsin K （CTSK）， and matrix metalloproteinase-9 （MMP-9） in the ankle joint tissues of rats were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The expressions of the proteins related to the bone erosion， including RANKL， CTSK， TRAP， MMP-9， and the proteins related to the PI3K/protein kinase B （Akt） signaling pathway， including PI3K， Akt， mammalian target of rapamycin （mTOR）， p-PI3K， phosphorylated protein kinase B （p-Akt）， and phosphorylated mammalian target of rapamycin （p-mTOR）， were detected by Western blot. ResultsCompared with the blank group， the modeling group showed marked ankle swelling and increased diameter. Micro-CT revealed an uneven articular surface and honeycomb-like bone erosion in the ankle joint. Quantitative analysis showed decreased BV/TV and increased BS/BV （P<0.05）. HE staining revealed a narrowed joint space， rough and discontinuous cartilage surfaces， reduced and unevenly distributed chondrocytes， partial hypertrophy， and blurred tidemarks， confirming successful model establishment. After four weeks of intervention， compared with those in the blank group， the rats in the model group exhibited severe ankle swelling and increased diameters （P<0.05）. Micro‑CT showed that the ankle joint surface was irregular， and bone erosion exhibited a honeycomb‑like morphology. The microstructural parameters of the bone revealed a decreased BV/TV and an increased BS/BV （P<0.05）. Histopathological examination revealed a narrowed joint space and severe articular cartilage destruction. The levels of uric acid in the serum and inflammatory factors （IL-1β， IL-6， and TNF-α） were increased （P<0.05）. The mRNA and protein levels of the proteins related to bone erosion in joint tissue， including RANKL， CTSK， TRAP， and MMP-9， were upregulated （P<0.05）. The ratios of p-PI3K/PI3K， p-Akt/Akt， and p-mTOR/mTOR in the proteins related to the PI3K/Akt signaling pathway were increased （P<0.05）. RANKL and p-PI3K protein fluorescence intensities were elevated （P<0.05）. Compared with those in the model group， the above indicators in all other administration groups showed varying degrees of improvement. The HSCD group and inhibitor groups exhibited more significant effects in reducing ankle swelling， improving bone erosion， bone microstructure （significant decrease in BV/TV and increase in BS/BV）， and the pathology of cartilage erosion， lowering inflammatory factor levels， downregulating the proteins related to the bone erosion， and suppressing activation of the PI3K/Akt/mTOR pathway （P<0.05）. The uric acid levels in rats' serum were reduced in both HSCD and allopurinol groups （P<0.05）. Compared with those in the HSCD group， the rats in the allopurinol group had larger ankle diameters （P<0.05）， more severe bone erosion and bone microstructure damage （P<0.05）， worse improvement of the pathology of cartilage erosion， higher levels of IL-6 and TNF-α （P<0.05）， elevated expressions of the proteins related to the bone erosion， higher expression ratio of proteins related to the PI3K/Akt signaling pathway （P<0.05）， and higher fluorescence intensities of RANKL and p-PI3K proteins （P<0.05）. The inhibitor group achieved comparable results to the HSCD group in improvements of bone microstructure and the reduction of IL-1β and IL-6， stronger suppression of TNF-α and PI3K/Akt/mTOR signaling pathway activation （P<0.05）， but weaker effects on cartilage repair and serum uric acid reduction （P<0.05）. ConclusionHSCD effectively reduces uric acid levels in serum， suppresses inflammatory factor secretion， and downregulates the expressions of proteins related to bone erosion， including RANKL， CTSK， TRAP， and MMP-9 in the joint tissues. Its action mechanism of improving gouty bone erosion may be associated with inhibition of the PI3K/Akt signaling pathway.

Abstract The prevalence of hypertension in children and adolescents continues to rise with a trend toward earlier onset, presenting a phenomenon that cannot be fully explained by traditional risk factor frameworks. Circadian rhythm disruption, particularly the dual disturbance of dietary and sleep rhythms, has emerged as a novel risk factor and become a research hotspot. The review systematically summarizes the epidemiological associations, biological mechanisms, and intervention strategies regarding dietary rhythm, sleep rhythm, and their co exposure with blood pressure in children and adolescents. Future research needs to focus on Chinese pediatric populations through longitudinal cohort studies and randomized controlled trials to clarify causal relationships and regulatory mechanisms, thereby providing evidence based guidance for chronic disease prevention and control in children.

Objective: To establish evidence-based, safe and efficient management of HIV-reactive blood donors by investigating safe and feasible assessment strategies for HIV-reactive blood donors based on routine blood screening data. Methods: The data of blood screening, supplementary testing, follow-up and CDC confirmation for HIV-reactive blood donors in our center from 2014 to 2024 were analyzed systematically to confirm HIV infection and identify infection status. Results: There were 1 235 samples (0.13%, 1 235/928 000) reactive in HIV blood screening over the 11-year period. A-mong them, 199 donors (16.11%) in asymptomatic HIV infection (HIV Ag/Ab++&HIV RNA+), 2(0.16%) as acute early HIV infection (HIV Ag/Ab+-&HIV RNA+) and 7(0.57%) as window-period infection (HIV RNA positive only) were confirmed. Donors with the result of HIV Ag/Ab+-&HIV RNA-(single-positive) were all excluded for HIV infection, while 1 in 6 HIV Ag/Ab++&HIV RNA-donors (double-positive) was confirmed to have HIV infection. When HIV Ag/Ab reagents were used continuously before and after the follow-up, it's observed in one reagent that the proportion of negative results in subsequent follow-up in single-positive donors who had negative results in the first sampling was significantly higher than the proportion of negative results in subsequent follow-up in those initially single-positive (P<0.05). But no significant difference was observed in another reagent (P>0.05). When reagents were changed in follow-up, the rate of singlepositive donors with negative results in the first sampling reached 96.7%, which was significantly higher than the negative rate of those without reagent changing in follow-up (P<0.05). Conclusion: Based on the serological and nucleic acid testing results of HIV blood screening, the confirmation of HIV infection and identification of infection status can be achieved accurately and efficiently. All HIV Ag/Ab+-&HIV RNA-donors were confirmed as false positive, and should be maintained their eligibilities for blood donation, but recommended to pass the retest before next donation. Using a different reagent for retesting helps improve the eligible rate. HIV Ag/Ab++&HIV RNA-donors should be deferred permanently due to the risk of true positivity.

Objective: To evaluate repeated testing on blood screening platforms in confirmation of non-discriminatory reactive (NDR) samples in nucleic acid testing (NAT). Methods: A total of 102 HBsAg-negative/NAT NDR samples were collected from voluntary blood donors at Dalian Blood Center between January 2021 and December 2023. Repeated testing was performed using two NAT platforms (Cobas s201 and Panther). For the first round of repeated testing, all samples were tested 12 times on each system; for the second round, the samples which were non-reactive or only reactive once in the first round were tested an additional 8 times. Anti-HBc and anti-HBs was detected using electrochemiluminescence assay (ECA). Meanwhile, blood donors were followed up. Results: The proportion of anti-HBc+ in 102 NDR samples was 88.2%. Forty-one samples (40.2%, 41/102) and 7 samples were confirmed HBV DNA+ in first-round and second-round repeated testing, respectively. The cumulative confirmation rate of HBV DNA+ was 47.1% (48/102) after repeated testing. Extra five blood donors detected HBV DNA+ in follow-up were identified as anti-HBc+ occult hepatitis B virus infection (OBI), while no window period infection was observed. Ultimately, there were 53 HBV infected donors confirmed, 46 HBV infection-unconfirmed, and 3 HBV uninfected. No significant difference was observed between the confirmation rate of the first-round testing and the cumulative confirmation rate after the second-round testing (P>0.05). The proportion of anti-HBc+ donors was quite high in both HBV infection-confirmed (98.1%) and unconfirmed group (82.6%), and donors with seronegative and anti-HBs-only occupied a high proportion in the latter (P<0.05). Conclusion: Numerous repeated testing of NDR samples using NAT platforms cannot achieve complete confirmation of HBV infection. Supplementary anti-HBc testing can minimize potential OBI risk among NDR donors, and is low-cost and efficient.

Senecavirus A (SVA) is a major viral pathogen causing disease in pigs, and effective monitoring of SVA infection is critical for disease control. In this study, we aimed to develop a reliable ELISA method for rapidly detecting neutralizing antibodies against SVA. We used HEK293F cells to express an SVA-specific porcine Fab antibody and verified the biological activity of the Fab antibody by indirect ELISA, immunofluorescence assay, virus neutralization test, and Western blotting. The Fab antibody was biotinylated and used as a competitive antibody to establish a competitive ELISA (C-ELISA) for detecting neutralizing antibodies against SVA. We then evaluated the C-ELISA in terms of sensitivity, specificity, repeatability, and result agreement rate with the VNT. The results showed that we successfully prepared an SVA-specific porcine Fab antibody, which showed high affinity for SVA. We named this antibody 1M33Fab and designated it as Bio-1M33Fab after biotin labeling. The assay conditions were optimized as follows: the coating concentration of SVA particles being 1 μg/mL, the working concentration of Bio-1M33Fab being 0.5 μg/mL, the optimal serum dilution of 1:10, and the optimal dilution of enzyme-labeled avidin being 1:30 000. At a percent inhibition (PI) of 47%, the assay demonstrated the highest sensitivity (96.88%) and specificity (100%), with no cross-reactivity observed with the positive sera of major porcine viral diseases. The intra-assay coefficient of variation ranged from 1.12% to 7.34%, while the inter-assay coefficient of variation ranged from 1.10% to 8.97%, indicating good repeatability. In the detection of 224 clinical pig serum samples, C-ELISA and VNT showed a result agreement rate of 93.75%. In conclusion, we successfully develop a C-ELISA method for detecting neutralizing antibodies against SVA by using a porcine-derived Fab antibody, which lays a foundation for the development of detection kits.
Animals ; Swine ; Antibodies, Neutralizing/immunology* ; Enzyme-Linked Immunosorbent Assay/methods* ; Immunoglobulin Fab Fragments/immunology* ; Antibodies, Viral/immunology* ; Picornaviridae/immunology* ; Humans ; HEK293 Cells ; Swine Diseases/diagnosis* ; Picornaviridae Infections/diagnosis*

This study aims to establish an antibody detection method for porcine deltacoronavirus (PDCoV). The recombinant proteins PDCoV-N1 and PDCoV-N2 were expressed via the prokaryotic plasmid pColdII harboring the N gene sequence of the PDCoV strain CH/XJYN/2016. The reactivity and specificity of PDCoV-N1 and PDCoV-N2 with anti-PEDV sera were analyzed after the recombinant proteins were analyzed by SDS-PAGE and purified by the Ni-NTA Superflow Cartridge. Meanwhile, Western blotting and indirect immunofluorescence assay were carried out separately to validate the recombinant proteins PDCoV-N1 and PDCoV-N2. Finally, we established an indirect ELISA method based on the recombinant protein PDCoV-N2 after optimizing the conditions and tested the sensitivity, specificity, and reproducibility of the method. Then, the established method was employed to examine 102 clinical serum samples. The recombinant protein PDCoV-N2 showed low cross-reactivity with anti-PEDV sera. The optimal conditions of the indirect ELISA method based on PDCoV-N2 were as follows: the antigen coating concentration of 1.25 μg/mL and coating at 37 ℃ for 1 h; blocking by BSA overnight at 4 ℃; serum sample dilution at 1:50 and incubation at 37 ℃ for 1 h; secondary antibody dilution at 1:80 000 and incubation at 37 ℃ for 1 h; color development with TMB chromogenic solution at 37 ℃ for 10 min. The S/P value ≥ 0.45, ≤0.38, and between 0.45 and 0.38 indicated that the test sample was positive, negative, and suspicious, respectively. The testing results of the antisera against porcine epidemic diarrhea virus (PEDV), porcine circovirus 2 (PCV2), transmissible gastroenteritis virus (TGEV), foot-and-mouth disease virus (FMDV), and African swine fever virus (ASFV) showed that the S/P values were all less than 0.38. The testing results of the 800-fold diluted anti-PDCoV sera were still positive. The results of the inter- and intra-batch tests showed that the coefficients of variation of this method were less than 10%. Clinical serum sample test results showed the coincidence rate between this method and neutralization test was 94.12%. In this study, an ELISA method for the detection of anti-PDCoV antibodies was successfully established based on the truncated N protein of PDCoV. This method is sensitive, specific, stable, and reproducible, serving as a new method for the clinical diagnosis of PDCoV.
Animals ; Enzyme-Linked Immunosorbent Assay/methods* ; Swine ; Antibodies, Viral/blood* ; Recombinant Proteins/genetics* ; Deltacoronavirus/isolation & purification* ; Coronavirus Infections/virology* ; Swine Diseases/diagnosis* ; Coronavirus Nucleocapsid Proteins ; Sensitivity and Specificity

ObjectiveTo analyze the epidemiological characteristics of clustered vomiting and diarrhea outbreaks in Minhang District of Shanghai, to identify the influencing factors of outbreak scale and duration of epidemic, and to provide scientific evidence for further strengthening surveillance early-warning efforts in key settings and for optimizing prevention and control measures. MethodsThe data for describing epidemiological characteristics of clustered vomitting and diarrhea outbreaks in Minhang District from 2018 to 2023 were collected, multivariable logistic regression models were applied to analyze the influencing factors for epidemic scale,and Spearman rank correlation analyses were applied to analyze the factors duration. ResultsA total of 136 clustered vomiting and diarrhea outbreaks were reported in Minhang District from 2018 to 2023, all occurring in school settings, with an overall attack rate of 0.90%. The outbreaks exhibited distinct seasonality, predominantly occurring from October to December (43.38%) and March to May (32.35%). The primary settings were preschools (45.59%) and elementary schools (44.12%), with students accounted for the majority of cases (99.48%). The predominant clinical manifestation was vomiting (90.44%), with person-to-person contact being the primary transmission route (98.53%). Norovirus genogroup Ⅱ was identified as the main pathogen (71.32%). Standardized terminal disinfection of outbreak sites (OR=0.39, 95%CI=0.20‒0.74) and effective isolation of affected classes (OR=0.23, 95%CI=0.09‒0.57) were significant protective factors for reducing outbreak scale. Both response time (r=0.64, P<0.001) and the number of case generations (r=0.71, P<0.001) showed positive correlations with outbreak duration. ConclusionSchools are the key settings for the prevention and control of clustered vomiting and diarrhea outbreaks in Minhang District, with peak occurring in autumn and spring. Early detection, timely reporting, and prompt response to outbreaks are crucial. Strengthening school-based surveillance systems and standardizing outbreak management protocols are of particular importance.

ObjectiveTo analyze the reported cases of infectious diseases across different tiers of public medical and healthcare institutions in Minhang District, Shanghai from 2013 to 2023, to investigate the status and changes in reported infectious diseases in this district from a temporal, etiological, and demographic perspectives, so as to provide a scientific basis for the construction of a hierarchica early-warning surveillance system under the grading diagnosis and treatment model in medical institutions, as well as for optimizing sentinel surveillance at facilities of different levels. MethodsA retrospective analysis was performed using surveillance data from the China Disease Prevention and Control Information System in Minhang District from 2013 to 2023. Reported infectious diseases were categorized into three categories based on transmission routes: respiratory infectious diseases, intestinal infectious diseases, and sexually transmitted and blood borne infectious diseases. According to the implementation phase of the grading diagnosis and treatment policy, the research time was divided into four time periods: 2013‒2016, 2017‒2019, 2020‒2022, and 2023. The distribution and temporal changes of reported cases of infectious diseases were compared across community health service centers (CHCs), secondary hospitals, tertiary grade-A hospitals and tertiary grade-B hospitals. Chi-square test was used for univariate analysis of differences in the number of reported cases. Quantitative data with normal distribution were analyzed using parametric tests, otherwise, Kruskal⁃Wallis H tests were used. ResultsThe proportions of total reported cases of infectious diseases in medical institutions at all levels in Minhang District, Shanghai from 2013 to 2023 were 10.66% in CHCs, 9.10% in secondary hospitals, 64.95% in tertiary grade-B hospitals, and 15.29% in tertiary grade-A hospitals, with an overall decline and then rebound trend in the reported cases. After the implementation of grading diagnosis and treatment policy, the number of reported cases in CHCs and secondary hospitals showed a trend of first decreasing and then increasing, while that in tertiary grade-B hospitals showed a steady decreasing trend and that in tertiary grade-A hospitals showed an increasing trend. In terms of the research periods divided above, a total of 10 392 cases were reported in 2013‒2016 (70.34% from tertiary grade-B hospitals and 12.59% from CHCs), including 2 922 cases of respiratory infectious diseases, 1 241 cases of intestinal infectious diseases, and 6 229 cases of sexually transmitted and blood-borne infectious diseases. Between 2017 and 2019, a total of 6 967 cases were reported (73.49% from tertiary grade-B hospitals and 11.84% from tertiary grade-A hospitals), including 2 983 cases of respiratory infectious diseases, 279 cases of intestinal infectious diseases, and 3 705 cases of sexually transmitted and blood-borne infectious diseases. Between 2020 and 2022, a total of 4 599 cases were reported (69.92% from tertiary grade-B hospitals and 24.57% from tertiary grade-A hospitals), including 1 627 cases of respiratory infectious diseases, 123 cases of intestinal infectious diseases, and 2 849 cases of sexually transmitted and blood-borne infectious diseases. In 2023, a total of 4 648 cases were reported (35.20% from tertiary grade-B hospitals and 27.50% from tertiary grade-A hospitals), including 3 165 cases of respiratory infectious diseases, 69 cases of intestinal infectious diseases, and 1 414 cases of sexually transmitted and blood-borne infectious diseases. The proportion of reported cases from tertiary grade-B hospitals was the highest in all the four research periods, but exhibited an obvious decrease in 2023. The differences in the reported cases of infectious diseases with different transmission routes among medical institutions at all levels were statistically significant (χ²=3 225.628, P<0.05). The differences in the mean age of patients among medical institutions at all levels were statistically significant (H=1 325.927, P<0.05). ConclusionThere are significant differences in the number of reported cases of infectious disease in the medical institutions at different levels. Tertiary grade-B hospitals have historically dominated the number of reported cases, but its share has declined recently. Whereas, CHCs and tertiary grade-A hospitals have played an increasingly important role in the surveillance and early warning of respiratory and intestinal infectious diseases. Therefore, it is recommended to leverage the strengths of grading diagnosis and treatment to establish targeted sentinel sites and deploy specialized teams tailored to the epidemiological characteristics of specific disease categories.