Objective:To correlate the expression of interleukin-6 (IL-6), CD40 ligand (CD40L), and soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) with regulatory T lymphocyte (Treg)/helper T lymphocyte 17 (Th17) in children with immune thrombocytopenic purpura (ITP) and to assess their combined diagnostic value.Methods:A retrospective study was conducted involving 80 children with ITP (ITP group) and 80 healthy children undergoing routine health screenings (control group) at Jinhua Central Hospital from February 2023 to February 2024. The levels of IL-6, CD40L, and sTREM-1, along with the Treg/Th17 ratio, were compared between the two groups and among children with different degrees of ITP severity. The correlations between IL-6, CD40L, and sTREM-1 and the severity of ITP, as well as the Treg/Th17 ratio were analyzed. Additionally, the diagnostic value of the combined tests was evaluated.Results:The levels of IL-6, CD40L, and sTREM-1 in the ITP group were (46.53 ± 8.69) ng/L, (6.51 ± 1.51), and (18.76 ± 3.72) ng/L, respectively. These values in the ITP group were significantly higher than those in the control group [(11.72 ± 1.58) ng/L, (4.31 ± 1.25), (8.07 ± 1.34) ng/L, t = 35.25, 10.04, 24.18, all P < 0.001]. The Treg/Th17 ratio in the ITP group was (1.34 ± 0.41), which was significantly lower than that in the control group [(13.56 ± 2.87), t = 37.70, P < 0.001]. In children with severe ITP, the levels of IL-6, CD40L, and sTREM-1 were (56.39 ± 11.70) ng/L, (9.62 ± 1.78), and (24.72 ± 4.81) ng/L, respectively. For those with moderate ITP, the levels were (45.41 ± 8.27) ng/L, (6.38 ± 1.40), and (17.69 ± 3.56) ng/L, respectively. In children with mild ITP, the levels were (37.04 ± 6.32) ng/L, (5.11 ± 1.32), and (14.50 ± 3.04) ng/L. The Treg/Th17 ratio in children with mild ITP was (0.95 ± 0.26), which was significantly lower than that in the moderate (1.37 ± 0.40) and severe (2.88 ± 0.56) groups. All differences were statistically significant among the three groups ( F = 23.98, 42.57, 37.15, 122.23, all P < 0.001). The levels of IL-6, CD40L, and sTREM-1 were positively correlated with the severity of ITP ( r = 0.565, 0.542, 0.538) and negatively correlated with the Treg/Th17 ratio ( r = -0.572, -0.536, -0.532), with all correlations being statistically significant (all P < 0.001). The receiver operating characteristic curve analysis indicated that the area under the curve values for the individual diagnoses of IL-6, CD40L, and sTREM-1 were 0.779, 0.750, and 0.763, respectively. In contrast, the area under the curve value for the combined diagnosis was 0.951, which was greater than that for each individual marker ( Z = 1.924, 2.137, 2.015, P = 0.037, 0.026, 0.031). Conclusions:The levels of IL-6, CD40L, and sTREM-1 in children with ITP are substantially correlated with the severity of ITP and the Treg/Th17 ratio, demonstrating notable diagnostic efficacy for ITP. Notably, the combination of IL-6, CD40L, and sTREM-1 greatly enhances diagnostic value.

Objective:To correlate the expression of interleukin-6 (IL-6), CD40 ligand (CD40L), and soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) with regulatory T lymphocyte (Treg)/helper T lymphocyte 17 (Th17) in children with immune thrombocytopenic purpura (ITP) and to assess their combined diagnostic value.Methods:A retrospective study was conducted involving 80 children with ITP (ITP group) and 80 healthy children undergoing routine health screenings (control group) at Jinhua Central Hospital from February 2023 to February 2024. The levels of IL-6, CD40L, and sTREM-1, along with the Treg/Th17 ratio, were compared between the two groups and among children with different degrees of ITP severity. The correlations between IL-6, CD40L, and sTREM-1 and the severity of ITP, as well as the Treg/Th17 ratio were analyzed. Additionally, the diagnostic value of the combined tests was evaluated.Results:The levels of IL-6, CD40L, and sTREM-1 in the ITP group were (46.53 ± 8.69) ng/L, (6.51 ± 1.51), and (18.76 ± 3.72) ng/L, respectively. These values in the ITP group were significantly higher than those in the control group [(11.72 ± 1.58) ng/L, (4.31 ± 1.25), (8.07 ± 1.34) ng/L, t = 35.25, 10.04, 24.18, all P < 0.001]. The Treg/Th17 ratio in the ITP group was (1.34 ± 0.41), which was significantly lower than that in the control group [(13.56 ± 2.87), t = 37.70, P < 0.001]. In children with severe ITP, the levels of IL-6, CD40L, and sTREM-1 were (56.39 ± 11.70) ng/L, (9.62 ± 1.78), and (24.72 ± 4.81) ng/L, respectively. For those with moderate ITP, the levels were (45.41 ± 8.27) ng/L, (6.38 ± 1.40), and (17.69 ± 3.56) ng/L, respectively. In children with mild ITP, the levels were (37.04 ± 6.32) ng/L, (5.11 ± 1.32), and (14.50 ± 3.04) ng/L. The Treg/Th17 ratio in children with mild ITP was (0.95 ± 0.26), which was significantly lower than that in the moderate (1.37 ± 0.40) and severe (2.88 ± 0.56) groups. All differences were statistically significant among the three groups ( F = 23.98, 42.57, 37.15, 122.23, all P < 0.001). The levels of IL-6, CD40L, and sTREM-1 were positively correlated with the severity of ITP ( r = 0.565, 0.542, 0.538) and negatively correlated with the Treg/Th17 ratio ( r = -0.572, -0.536, -0.532), with all correlations being statistically significant (all P < 0.001). The receiver operating characteristic curve analysis indicated that the area under the curve values for the individual diagnoses of IL-6, CD40L, and sTREM-1 were 0.779, 0.750, and 0.763, respectively. In contrast, the area under the curve value for the combined diagnosis was 0.951, which was greater than that for each individual marker ( Z = 1.924, 2.137, 2.015, P = 0.037, 0.026, 0.031). Conclusions:The levels of IL-6, CD40L, and sTREM-1 in children with ITP are substantially correlated with the severity of ITP and the Treg/Th17 ratio, demonstrating notable diagnostic efficacy for ITP. Notably, the combination of IL-6, CD40L, and sTREM-1 greatly enhances diagnostic value.

Objective:This study aims to explore whether there are specific behavioral deficits of response inhibition and emotional processing in patients with checking obsessive-compulsive disorder (OCD) and those with washing OCD.Methods:A cross-sectional study was conducted from January 2020 to December 2022, collecting clinical data from 75 OCD patients at the outpatient psychological consultation clinic of Xiangya Second Hospital and the clinical psychology department of Hunan Brain Hospital. The sample included 40 OCD patients with checking type (checking group, 24 males, 16 females, aged 14-34 years, mean age 22.1±5.0 years) and 35 OCD patients with washing type (washing group, 12 males, 23 females, aged 14-41 years, mean age 22.6±6.7 years). An age-matched healthy control group (control group) of 80 individuals (HCs, 37 males and 43 females, aged 14-25 years, mean age 20.8±1.9 years) was also recruited. All participants completed the Go/No-go task and Hariri task with behavioral data recorded. The Dimensional Yale-Brown Obsessive-Compulsive Scale was used to assess the severity of OCD symptoms. The Center for Epidemiologic Studies Depression Scale (CES-D) and State Anxiety Inventory (STAI) were used to assess the severity of depression and anxiety. A 3 (group: checking OCD, washing OCD and HC)×2 (task type: Go vs. No-go/Shape vs. Face) repeated-measures ANOVA was conducted to compare the behavioral performance across tasks.Results:Compared with HC group, both checking OCD group and washing OCD group had significantly higher scores in depression and anxiety ( F=85.43, 32.33,both P<0.05). When performing Go/No-go task, a significant group×task interaction effect was observed ( F3(2, 152)=3.23, P3=0.042, partialη32=0.04). In the checking OCD group, No-go accuracy was significantly lower than Go accuracy (accuracy=0.821 vs. 0.893, P<0.001); the checking OCD had significantly lower accuracy than HC in the No-go task (accuracy=0.821 vs. 0.876, P=0.005); there were no significant group differences between the washing OCD and HC in the No-go task ( P>0.05). When performing Hariri task, a significant group×task interaction effect was found ( F3(2, 152)=4.91, P3=0.009, partial η32=0.06). The washing OCD group showed significantly lower accuracy in matching emotional faces than the control group (0.879 vs. 0.936, P=0.001), whereas the checking OCD group showed no significant difference from the HC ( P>0.05); there were no significant group differences in shape matching task ( P>0.05). The accuracy of shape matching task was significantly higher than face matching task in the three groups (shape: checking OCD=0.936,washing OCD=0.929,HC=0.943; face:checking OCD=0.877,washing OCD=0.844,HC=0.917;all P>0.05). Conclusions:Checking OCD and washing OCD exhibit distinct behavioral impairment patterns in response inhibition and emotional processing. Checking-type OCD is primarily characterized by impaired response inhibition, whereas washing-type OCD is mainly associated with deficits in emotion processing.

Objective:This study aims to explore whether there are specific behavioral deficits of response inhibition and emotional processing in patients with checking obsessive-compulsive disorder (OCD) and those with washing OCD.Methods:A cross-sectional study was conducted from January 2020 to December 2022, collecting clinical data from 75 OCD patients at the outpatient psychological consultation clinic of Xiangya Second Hospital and the clinical psychology department of Hunan Brain Hospital. The sample included 40 OCD patients with checking type (checking group, 24 males, 16 females, aged 14-34 years, mean age 22.1±5.0 years) and 35 OCD patients with washing type (washing group, 12 males, 23 females, aged 14-41 years, mean age 22.6±6.7 years). An age-matched healthy control group (control group) of 80 individuals (HCs, 37 males and 43 females, aged 14-25 years, mean age 20.8±1.9 years) was also recruited. All participants completed the Go/No-go task and Hariri task with behavioral data recorded. The Dimensional Yale-Brown Obsessive-Compulsive Scale was used to assess the severity of OCD symptoms. The Center for Epidemiologic Studies Depression Scale (CES-D) and State Anxiety Inventory (STAI) were used to assess the severity of depression and anxiety. A 3 (group: checking OCD, washing OCD and HC)×2 (task type: Go vs. No-go/Shape vs. Face) repeated-measures ANOVA was conducted to compare the behavioral performance across tasks.Results:Compared with HC group, both checking OCD group and washing OCD group had significantly higher scores in depression and anxiety ( F=85.43, 32.33,both P<0.05). When performing Go/No-go task, a significant group×task interaction effect was observed ( F3(2, 152)=3.23, P3=0.042, partialη32=0.04). In the checking OCD group, No-go accuracy was significantly lower than Go accuracy (accuracy=0.821 vs. 0.893, P<0.001); the checking OCD had significantly lower accuracy than HC in the No-go task (accuracy=0.821 vs. 0.876, P=0.005); there were no significant group differences between the washing OCD and HC in the No-go task ( P>0.05). When performing Hariri task, a significant group×task interaction effect was found ( F3(2, 152)=4.91, P3=0.009, partial η32=0.06). The washing OCD group showed significantly lower accuracy in matching emotional faces than the control group (0.879 vs. 0.936, P=0.001), whereas the checking OCD group showed no significant difference from the HC ( P>0.05); there were no significant group differences in shape matching task ( P>0.05). The accuracy of shape matching task was significantly higher than face matching task in the three groups (shape: checking OCD=0.936,washing OCD=0.929,HC=0.943; face:checking OCD=0.877,washing OCD=0.844,HC=0.917;all P>0.05). Conclusions:Checking OCD and washing OCD exhibit distinct behavioral impairment patterns in response inhibition and emotional processing. Checking-type OCD is primarily characterized by impaired response inhibition, whereas washing-type OCD is mainly associated with deficits in emotion processing.

Methods:A total of 392 patients with seasonal allergic rhinitis were selected from the population of the epidemiological investigation project of allergic diseases in Hohhot, Inner Mongolia. The project was led by Department of Allergy, Beijing Shijitan Hospital, Capital Medical University, and assisted by Hohhot First Hospital from April to May 2023. The patients were randomly divided into a spleen aminopeptide group (296 cases) and control group (96 cases) at a ratio of 3∶1, and the enrollment period was from June 1 to 14, 2023. The treatment group was treated with spleen aminopeptide oral solution for 12 weeks starting from 4-6 weeks (±7 days) before the pollen dispersal period, while the control group was treated with a simulated agent of spleen aminopeptide oral solution. Both the treatment group and the control group were treated with oral antihistamines and/or nasal glucocorticoids as needed during the pollen dispersal period. Evaluate the therapeutic effect by comparing the symptom scores, drug scores and quality of life scores of the two groups, and detect the expression levels of cytokines in serum. Symptom scores, quality of life scores, drug scores and laboratory results were compared by independent sample t test/Kruskal-Wallis test and χ2 test/Fisher′s exact test. Results:Compared with the control group, spleen aminopeptide treatment for 12 weeks significantly improved symptoms of nasal congestion [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=6.308, P<0.05], nasal itching [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=4.966, P<0.05], sneezing [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=5.245, P<0.05], runny nose [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=5.41, P<0.05] and tearing [ M( Q1, Q3):1(0, 2) vs. 1(0, 3), H=4.664, P<0.05]. At 12 weeks of treatment, the scores of nasal symptoms and ocular symptoms in control group and experimental group were significantly increased compared with baseline ( P<0.05). In experimental group, nasal congestion [ M( Q1, Q3):1(0, 1) vs. 1(0, 2), H=4.042, P<0.05], eye itching/foreign body sensation/redness symptom scores [ M( Q1, Q3):1(0, 2) vs. 1(0, 2), H=5.302, P<0.05] and total scores [ M( Q1, Q3):4(-1, 9) vs. 5(0, 12.5), H=3.958, P<0.05] were significantly increased. The antihistamine drug score of the splenic peptide treatment group at 6 weeks were lower than that of the control group ( H=4.232, P<0.05). After 12 weeks of treatment, the antihistamine drug score [ M( Q1, Q3):10(0, 24) vs. 19(2, 36.5), H=6.67, P<0.05] and the total drug score [ M( Q1, Q3):28.5(5, 77.5) vs. 46(6, 155.5), H=3.995, P<0.05] were significantly lower than those of the control group. The serum IL-17A levels of the treatment group were significantly lower than those of the control group after 6 weeks (0.7±1.77 vs. 0.85±1.67 ,H=10.08, P<0.05) and 12 weeks (0.81±1.63 vs. 0.94±1.73, H=5.196, P<0.05) of splenic aminopeptide treatment. Conclusions:Early treatment with spleen aminopeptide oral solution can significantly improve nasal and ocular symptoms of patients with seasonal allergic rhinitis, reduce the use of drugs during the onset period, and improve the quality of life. It may exert an immunomodulatory effect by reducing the expression level of IL-17A in the serum of patients.Objects:To conduct a study on the prevention and treatment of seasonal allergic rhinitis in Hohhot, Inner Mongolia, evaluate the preventive and therapeutic effects of spleen aminopeptide oral solution on seasonal allergic rhinitis, and explore its related mechanisms.

BACKGROUND:Swimming is an important non-pharmacological treatment for knee osteoarthritis,which can effectively alleviate the disease.However,the effect and mechanism of swimming on senile knee osteoarthritis are still unclear. OBJECTIVE:To investigate the effect of swimming exercise on the articular cartilage of aged mice with knee osteoarthritis. METHODS:Six 3-month-old male C57BL/6 mice were selected as the young group,and twelve 18-month-old male C57BL/6 mice were randomized into the aged group and the swimming group,with six mice in each group.Mice in the swimming group received adaptive swimming for 1 week and formal swimming for 8 weeks.After the intervention,stride length analysis and sampling were performed in each group.The total number of leukocytes and lymphocytes in peripheral blood was detected by blood routine examinations.The morphology of the articular cartilage was observed by hematoxylin-eosin and safranin O-fast green staining.Chondrocyte counts and the modified Mankin's score were used to evaluate the degree of articular cartilage damage.The protein and mRNA expressions of type Ⅱ collagen,aggrecan and matrix metalloproteinase 13 in articular cartilage were detected by immunohistochemical staining and RT-qPCR. RESULTS AND CONCLUSION:Compared with the young group,the mice in the aged group showed significantly decreased stride length(P＜0.05),significantly increased numbers of peripheral leukocytes and lymphocytes(P＜0.05),significantly decreased count of chondrocytes(P＜0.05),significantly increased modified Mankin's score(P＜0.05),significantly decreased protein and mRNA expression of type Ⅱ collagen and aggreca(P＜0.05),and significantly increased matrix metalloproteinase 13 expression(P＜0.05).Moreover,hematoxylin-eosin and safranin O-fast green staining showed the uneven surface of the articular cartilage,abnormal chondrocytes,and proteoglycan loss in the aged group.Compared with the aged group,swimming exercise significantly improved the stride length of mice(P＜0.05),decreased the count of peripheral blood lymphocytes(P＜0.05),increased the count of chondrocytes(P＜0.05),decreased the modified Mankin's score(P＜0.05),increased the protein and mRNA expression of type Ⅱ collagen and aggrecan(P＜0.05),and decreased the expression of matrix metalloproteinase 13(P＜0.05).Hematoxylin-eosin and safranin O-fast green staining showed that the articular surface of mice in the swimming group was smooth,chondrocytes were normal,and proteoglycan loss was less.All these findings indicate that swimming exercise can reduce the number of inflammatory cells in the blood of aged mice,improve articular chondrocytes,matrix composition and cartilage tissue morphology;thus,it has a protective effect on the cartilage of aged mice with knee osteoarthritis.

Methods:A total of 392 patients with seasonal allergic rhinitis were selected from the population of the epidemiological investigation project of allergic diseases in Hohhot, Inner Mongolia. The project was led by Department of Allergy, Beijing Shijitan Hospital, Capital Medical University, and assisted by Hohhot First Hospital from April to May 2023. The patients were randomly divided into a spleen aminopeptide group (296 cases) and control group (96 cases) at a ratio of 3∶1, and the enrollment period was from June 1 to 14, 2023. The treatment group was treated with spleen aminopeptide oral solution for 12 weeks starting from 4-6 weeks (±7 days) before the pollen dispersal period, while the control group was treated with a simulated agent of spleen aminopeptide oral solution. Both the treatment group and the control group were treated with oral antihistamines and/or nasal glucocorticoids as needed during the pollen dispersal period. Evaluate the therapeutic effect by comparing the symptom scores, drug scores and quality of life scores of the two groups, and detect the expression levels of cytokines in serum. Symptom scores, quality of life scores, drug scores and laboratory results were compared by independent sample t test/Kruskal-Wallis test and χ2 test/Fisher′s exact test. Results:Compared with the control group, spleen aminopeptide treatment for 12 weeks significantly improved symptoms of nasal congestion [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=6.308, P<0.05], nasal itching [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=4.966, P<0.05], sneezing [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=5.245, P<0.05], runny nose [ M( Q1, Q3):2(1, 2) vs. 2(1, 3), H=5.41, P<0.05] and tearing [ M( Q1, Q3):1(0, 2) vs. 1(0, 3), H=4.664, P<0.05]. At 12 weeks of treatment, the scores of nasal symptoms and ocular symptoms in control group and experimental group were significantly increased compared with baseline ( P<0.05). In experimental group, nasal congestion [ M( Q1, Q3):1(0, 1) vs. 1(0, 2), H=4.042, P<0.05], eye itching/foreign body sensation/redness symptom scores [ M( Q1, Q3):1(0, 2) vs. 1(0, 2), H=5.302, P<0.05] and total scores [ M( Q1, Q3):4(-1, 9) vs. 5(0, 12.5), H=3.958, P<0.05] were significantly increased. The antihistamine drug score of the splenic peptide treatment group at 6 weeks were lower than that of the control group ( H=4.232, P<0.05). After 12 weeks of treatment, the antihistamine drug score [ M( Q1, Q3):10(0, 24) vs. 19(2, 36.5), H=6.67, P<0.05] and the total drug score [ M( Q1, Q3):28.5(5, 77.5) vs. 46(6, 155.5), H=3.995, P<0.05] were significantly lower than those of the control group. The serum IL-17A levels of the treatment group were significantly lower than those of the control group after 6 weeks (0.7±1.77 vs. 0.85±1.67 ,H=10.08, P<0.05) and 12 weeks (0.81±1.63 vs. 0.94±1.73, H=5.196, P<0.05) of splenic aminopeptide treatment. Conclusions:Early treatment with spleen aminopeptide oral solution can significantly improve nasal and ocular symptoms of patients with seasonal allergic rhinitis, reduce the use of drugs during the onset period, and improve the quality of life. It may exert an immunomodulatory effect by reducing the expression level of IL-17A in the serum of patients.Objects:To conduct a study on the prevention and treatment of seasonal allergic rhinitis in Hohhot, Inner Mongolia, evaluate the preventive and therapeutic effects of spleen aminopeptide oral solution on seasonal allergic rhinitis, and explore its related mechanisms.

OBJECTIVE To investigate the effect of salidroside (Sal) on bone loss in obstructive sleep apnea syndrome(OSAS) rats by regulating the osteoprotegerin(OPG)/receptor activator of nuclear factor kappa-B ligand(RANKL) pathway. METHODS Rats were randomly divided into(12 rats/group) control group,OSAS group,Sal-L,Sal-M,and Sal-H groups(17.5,35,70 mg/kg). Except for the control group,all other groups were used to replicate the OSAS rat model through hypoxia and reoxygenation cycles. Bone density meters,three-point bending experiments,and Micro CT were applied to measure the bone density,biomechanics,and microstructural changes of the femur in rats. ELISA method was applied to detect serum levels of osteocalcin(BGP),alkaline phosphatase(ALP),and cross-linked carboxy-terminal telopeptide of type Ⅰ collagen(CTX-I). RT-PCR was applied to detect OPG and RANKL mRNA levels in the femur. Western blotting was applied to detect the expression of OPG/RANKL pathway proteins in the femur. RESULTS Compared with the control group,the bone density,maximum intensity,maximum load,trabecular bone volume fraction(Tb.BV/TV),trabecular number(Tb.N),trabecular thickness(Tb.Th),BGP,ALP,OPG mRNA and protein expression,OPG/RANKL ratio of rats in the OSAS group were decreased,the mRNA and protein expression of CTX-I and RANKL were increased(P<0.05). Compared with the OSAS group,the bone density,maximum intensity,maximum load,Tb.BV/TV,Tb.N,Tb.Th,BGP,ALP,OPG mRNA and protein expression,OPG/RANKL ratio of rats in the Sal-L,Sal-M,and Sal-H groups were increased sequentially,the mRNA and protein expression of CTX-I and RANKL were decreased sequentially,the above changes were most great in the Sal-H group(P<0.05). CONCLUSION Salidroside promotes bone formation and inhibits bone resorption by increasing OPG expression and decreasing RANKL expression,thereby reducing bone loss in OSAS rats.

Bone organoids can simulate the complex structure and function of the bone tissues, which makes them a frontier technology in organoid researches. Bone organoids show a tremendous potential of applications in bone disease modeling, bone injury repair, and medicine screening. Although advancements have been made so far in constructing bone organoids with functional structures like mineralization, bone marrow, trabecular bone, callus, woven bone, etc, the researches in this field are confronted with numerous challenges such as lack of standardized construction strategies and unified evaluation criteria, which limits their further promotion and application. To standardize researches in bone organoids, the Orthopedic Expert Committee of Geriatric Branch of Chinese Association of Gerontology and Geriatrics, the Youth Osteoporosis Group of Orthopedic Branch of Chinese Medical Association, the Osteoporosis Group of Orthopedic Surgeon Branch of Chinese Medical Doctor Association, and the Osteoporosis Committee of Shanghai Association of Integrated Traditional Chinese and Western Medicine organized related experts to formulate Expert consensus on the construction, evaluation, and application of bone organoids ( version 2024) based on an evidence-based approach. A total of 17 recommendations were put forth, aiming to standardize researches and clinical applications of bone organoids and enhance their value in scientific research and clinical practice.

ObjectiveTo analyze the epidemic intensity and characteristics of influenza in Changzhou City， Jiangsu Province from 2019 to 2023， and to provide scientific evidence for the formulation of influenza prevention and control strategies. MethodsThe surveillance data of influenza surveillance sentinel hospitals in Changzhou City from April 2019 to March 2023 were collected through the China influenza surveillance information system. Influenza-like illness （ILI） cases before and after the pandemic of COVID-19 in Changzhou City were analyzed， and the differences among qualitative data were compared by using χ^² test. ResultsFrom April 2019 to March 2023 the percentages of ILI cases’ medical visits in the four-influenza surveillance year were 2.57%， 1.84%， 5.38%， and 3.66%， respectively， and the positive detection rates of influenza virus were 25.71%， 0.44%， 22.78%， and 24.32%， respectively. The number of influenza outbreaks was 61， 1， 23， and 128， respectively. ILI cases were mainly among adolescent children aged 5‒14 years. The percentage of ILI cases in 2020‒2021 after the pandemic of COVID-19 was significantly lower than that in 2019‒2020 （χ²=737.342， P<0.001）， and the percentage of ILI cases in 2021‒2023 was higher than that in 2019‒2020. Influenza viruses in 2019‒2021 were dominated by type B Victoria， and influenza A virus was the dominant strain in positive influenza virus detections in 2022‒2023. The number of influenza outbreaks in 2021‒2023 was significantly lower than that in 2019‒2020 （χ²=185.662， P<0.001）. ConclusionThe epidemiological characteristics of influenza are different in different stages of COVID-19 prevention and control during 2019‒2023. In the dynamic clearance phase of COVID-19， ILI case’s medical visits showed low-level fluctuations without obvious seasonal fluctuations， and influenza virus was dominated by type B. In the high-intensity phase of the pandemic， the level of ILI case’s medical visits has reached the peak of the calendar year， and the positive detection of influenza virus was dominated by type A H3N2. In the "Category B B control" phase， the level of ILI case’s medical visits increased after a rapid decline， and the positive detection of influenza virus was dominated by type A H1N1. It is necessary to further strengthen the monitoring of influenza cases， pay close attention to the changes in influenza strains， actively promote influenza vaccination for key population group， and promote health behavior changes for the whole population.