Objective To analyze the influencing factors of malaria infection of labor service exported to overseas in Langfang City, in order to establish a visualization tool to assist clinicians in predicting the risk of malaria. Methods A total of 4 774 expatriate employees of the Nibei Pipeline Project of the Pipeline Bureau from October 2021 to August 2023 were taken as the subjects, and the gender, age, overseas residence area and Knowledge of malaria controlscores of the study subjects were investigated by questionnaire survey, and the possible risk factors of malaria were screened by logistic regression model. At the same time, the nomogram prediction model was established, and the subjects were divided into the training group and the validation group at a ratio of 2:1, and the area under the curve (ROC) and the decision curve were plotted to evaluate the prediction ability and practicability of the prediction model in this study. Results Among the 4 774 study subjects, 96 cases of malaria occurred, and the detection rate was 2.01%. Junior school （OR=1.723，95% CI:1.361-2.173）， and residence in rural areas（OR=2.091，95%CI:1.760 -3.100）were risk factors (OR>1), while protective measures（OR=0.826，95% CI : 0.781 - 0.901） and high malaria education scores （OR=0.872，95% CI : 0.621 - 0.899）were protective factors.The nomogram prediction model results showed that the area under the curve of the nomogram prediction model in the training group was 0.94 (95% CI : 0.85 - 1.00), while the validation group was 0.93 (95% CI : 0.80 - 1.00). The results of the decision curve showed that when the threshold probability of the population was 0-0.9, the nomogram model was used to predict the risk of malaria occurrence with the highest net income. Conclusion The nomogram prediction model (including gender, education, region, protection and malaria education score) established and validated in this study is of great value for clinicians to screen high-risk patients with malaria.

Objective To explore the expression and clinical significance of tissue inhibitor of matrix metal-loproteinases(TIMP)-1 and pentraxin-3(PTX3)in the serum of patients with obstructive sleep apnea-hypop-nea syndrome(OSAHS).Methods A total of 120 patients with OSAHS admitted to the hospital from 2021 to 2022 were selected as the study group,and another 114 healthy people who underwent the physical exami-nation in the same period were selected as the control group.The severity of OSAHS was determined accord-ing to the apnea-hypopnea index(AHI)and the minimum oxygen saturation(LSpO2),and the patients were divided into mild group(66 cases)and the moderate-severe group(54 cases).Serum TIMP-1 and PTX3 levels were measured by enzyme-linked immunosorbent assay.Pearson method was used to analyze the correlation between serum TIMP-1,PTX3 and AHI,LSpO2.Receiver operating characteristic(ROC)curve was used to analyze the predictive value of serum TIMP-1 and PTX3 on the severity of disease in patients with OSAHS.Logistic regression was used to analyze the factors influencing the severity of the disease in OSAHS patients.Results Serum TIMP-1,PTX3 and AHI levels in the study group were higher than those in the control group,and LSpO2 level was lower than that in the control group(P<0.05).The body mass index(BMI),the proportion of hypertension history,the proportion of coronary heart disease history,the levels of total choles-terol,triglycerides,low-density lipoprotein cholesterol,TIMP-1,PTX3 and AHI in the moderate-severe group were significantly higher than those in the mild group,and the high density lipoprotein cholesterol,LSpO2 lev-el was significantly lower than that in the mild group(P<0.05).Pearson method results showed that serum TIMP-1,PTX3 levels were positively correlated with AHI(r=0.428,0.392,P<0.05),and serum TIMP-1,PTX3 levels were negatively correlated with LSpO2(r=-0.645,-5.836,P<0.05).The results of the ROC curve showed that the area under the curve(AUC)of serum TIMP-1 and PTX3 alone predicted the severity of the patients'disease was 0.813 and 0.777,with cut-off values were 2.47 μg/L and 7.23 ng/L,with the sensi-tivity of 70.37%and 77.78%and the specificity of 77.27%and 72.23%,respectively.The AUC for predic-ting the severity of patients'disease by combining the two was 0.866,which was significantly higher than those of serum TIMP-1(Z=2.067,P=0.039)and PTX3 alone(Z=2.331,P=0.020).Logistic regression a-nalysis showed that TIMP-1,PTX3,history of hypertension,and history of coronary artery disease,AHI and LSpO2 were influential factors for severity of disease in patients with OSAHS(P<0.05).Conclusion TIMP-1 and PTX3 are both up-regulated in the serum of OSAHS patients and closely related to the severity of the disease,and they are the influential factors in the severity of OSAHS patients.

Background: Interferon lambda receptor 1 (IFNLR1) is a type II cytokine receptor that clings to interleukins IL-28A, IL29B, and IL-29 referred to as type III IFNs (IFN-λs). IFN-λs act through the JAK-STAT signaling pathway to exert antiviral effects related to preventing and curing an infection. Although the immune function of IFN-λs in virus invasion has been described, the molecular mechanism of IFNLR1 in that process is unclear. Objectives: The purpose of this study was to elucidate the role of IFNLR1 in the pathogenesis and treatment of porcine reproductive and respiratory syndrome virus (PRRSV). Methods: The effects of IFNLR1 on the proliferation of porcine alveolar macrophages (PAMs) during PRRSV infection were investigated using interference and overexpression methods. Results: In this study, the expressions of the IFNLR1 gene in the liver, large intestine, small intestine, kidney, and lung tissues of Dapulian pigs were significantly higher than those in Landrace pigs. It was determined that porcine IFNLR1 overexpression suppresses PRRSV replication. The qRT-PCR results revealed that overexpression of IFNLR1 upregulated antiviral and IFN-stimulated genes. IFNLR1 overexpression inhibits the proliferation of PAMs and upregulation of p-STAT1. By contrast, knockdown of IFNLR1 expression promotes PAMs proliferation. The G0/G1 phase proportion in IFNLR1-overexpressing cells increased, and the opposite change was observed in IFNLR1-underexpressing cells. After inhibition of the JAK/STAT signaling pathway, the G2/M phase proportion in the IFNLR1-overexpressing cells showed a significant increasing trend. In conclusion, overexpression of IFNLR1 induces activation of the JAK/STAT pathway, thereby inhibiting the proliferation of PAMs infected with PRRSV. Conclusion Expression of the IFNLR1 gene has an important regulatory role in PRRSVinfected PAMs, indicating it has potential as a molecular target in developing a new strategy for the treatment of PRRSV.

Objective:To evaluate the implementation of the China Healthcare Improvement Initiative(CHII)from 2018 to 2020 in 143 tertiary public hospitals in China.Methods:In March 2019 and from January to March in 2021, 143 tertiary public hospitals in 31 provinces of China were investigated using the unified " medical institution questionnaire Ⅰ" and " medical institution Questionnaire Ⅱ" . The data were collected by means of hospital self-report and expert on-site scoring. Descriptive and inferential statistical analysis were used to analyze the data, and the data of two cross-sectional surveys were compared and analyzed.Results:The average score rate of implementing CHII in 143 sample hospitals in 2020 was 88.9%, which was higher than that in 2018(84.4%). The appointment diagnosis and treatment system, clinical pathway management system, day service, smart hospital and humanistic service were significantly improved. In 2020, the average score rate of logistics service, high quality nursing service and clinical pathway management system was higher than 95%, while the average score rate of day service, telemedicine system and medical social work system was lower than 85%. The total score rate of general hospitals was significantly higher than that of specialized hospitals( P<0.001). In 2020, the proportion of hospitals with full marks in 29 secondary indicators(74.4%)was more than 80%, reaching the standard level. Conclusions:The implementation level of CHII in tertiary public hospitals in China has been improved continuously and made significant progress, but some dimensions and indicators need to be further improved.

Objective:To analyze the correlation between serum ferritin (SF), perilipin, leptin and the outcome of patients with gestational diabetes mellitus (GDM).Methods:From October 2017 to December 2019, 126 patients with GDM who underwent maternity checkups in Baoding Fourth Central Hospital and gave birth were selected as the GDM group, and 82 normal pregnant women during the same period were selected as the control group for retrospective analysis. The levels of serum SF, perilipin, and leptin in the GDM group and the control group were measured and compared, and the expressions of serum indexes of patients with different blood glucose control and different pregnancy outcomes in the GDM group were measured. Pearson correlation analysis was used to explore the correlation between the expression of serum indexes in GDM patients and fasting blood glucose (FPG), 2 h postprandial blood glucose (2 h PG), and insulin resistance index (HOMA-IR). Logistic regression was used to analyze the relationship between the expression of serum indicators and adverse pregnancy outcomes in GDM patients. The receiver operating characteristic (ROC) curve was used to observe the value of single serum indexes and to predict the pregnancy outcome of GDM patients.Results:The levels of SF, perilipin and leptin in GDM group were higher than those in control group: (152.48 ± 37.64) μg/L vs. (109.27 ± 32.16) μg/L, (857.06 ± 192.35) ng/L vs. (262.83 ± 104.7) ng/L, (23.54 ± 2.28) μg/L vs.(14.62 ± 1.83) μg/L, the differences were statistically significant ( P<0.05). The levels of SF, perilipin and leptin in patients with good blood glucose control in GDM group were lower than those in patients with poor blood glucose control: (132.10 ± 36.52) μg/L vs. (176.37 ± 40.06) μg/L, (176.37 ± 40.06) ng/L vs. (946.42 ± 205.37) ng/L, (21.49 ± 2.16) μg/L vs. (25.94 ± 2.40) μg/L, the differences were statistically significant ( P<0.05). The levels of serum SF, perilipin and leptin in GDM patients were positively correlated with FPG, 2 h PG and HOMA-IR levels ( P<0.05). The levels of serum SF, perilipin and leptin in GDM patients with adverse pregnancy outcomes were higher than those in patients without occurrence: (182.86 ± 42.29) μg/L vs. (138.86 ± 35.47) μg/L, (1 013.35 ± 216.07) ng/L vs. (787.00 ± 183.49) ng/L, (27.04 ± 2.5) μg/L vs. (21.97 ± 2.07) μg/L, the differences were statistically significant ( P<0.05). Logistic regression analysis showed that serum SF, perilipin and leptin were closely related to the adverse pregnancy outcomes in GDM patients ( P<0.05). ROC curve analysis showed that the sensitivity and the specificity of SF, perilipin, leptin combined detection to predict GDM patients with adverse pregnancy outcomes was 76.92% and 83.91%. Conclusions:The serum SF, perilipin and leptin are abnormally high expression in GDM patients, and it is positively correlated with blood glucose level and HOMA-IR. Joint detection can improve the predictive value of adverse pregnancy outcomes and provide a basis for early intervention.

Background: Interferon lambda receptor 1 (IFNLR1) is a type II cytokine receptor that clings to interleukins IL-28A, IL29B, and IL-29 referred to as type III IFNs (IFN-λs). IFN-λs act through the JAK-STAT signaling pathway to exert antiviral effects related to preventing and curing an infection. Although the immune function of IFN-λs in virus invasion has been described, the molecular mechanism of IFNLR1 in that process is unclear. Objectives: The purpose of this study was to elucidate the role of IFNLR1 in the pathogenesis and treatment of porcine reproductive and respiratory syndrome virus (PRRSV). Methods: The effects of IFNLR1 on the proliferation of porcine alveolar macrophages (PAMs) during PRRSV infection were investigated using interference and overexpression methods. Results: In this study, the expressions of the IFNLR1 gene in the liver, large intestine, small intestine, kidney, and lung tissues of Dapulian pigs were significantly higher than those in Landrace pigs. It was determined that porcine IFNLR1 overexpression suppresses PRRSV replication. The qRT-PCR results revealed that overexpression of IFNLR1 upregulated antiviral and IFN-stimulated genes. IFNLR1 overexpression inhibits the proliferation of PAMs and upregulation of p-STAT1. By contrast, knockdown of IFNLR1 expression promotes PAMs proliferation. The G0/G1 phase proportion in IFNLR1-overexpressing cells increased, and the opposite change was observed in IFNLR1-underexpressing cells. After inhibition of the JAK/STAT signaling pathway, the G2/M phase proportion in the IFNLR1-overexpressing cells showed a significant increasing trend. In conclusion, overexpression of IFNLR1 induces activation of the JAK/STAT pathway, thereby inhibiting the proliferation of PAMs infected with PRRSV. Conclusion Expression of the IFNLR1 gene has an important regulatory role in PRRSVinfected PAMs, indicating it has potential as a molecular target in developing a new strategy for the treatment of PRRSV.

Objective:To understand the overall satisfaction rate with vaccination services in parents of children, and the impact of additional time consumed for vaccination service on overall satisfaction rate.Methods:From December 2019 to January 2020, a total of 3 178 parents of 0-3 years old children were investigated to collect the information about their basic characteristics, additional time spent for vaccination service and overall satisfaction through questionnaires. Binary logistic regression model and restricted cubic spline model were used to evaluate the impact of additional time spend on the overall satisfaction rate.Results:The overall satisfaction rate of parents with vaccination services was 92.32%. The median time for parents to move from home to vaccination clinic was 10.00 (10.00, 20.00) minutes, the median waiting time to make an appointment was 10.00 (5.00, 15.00) minutes, the median waiting time for vaccination was 5.00 (3.00, 10.00) minutes, and the median total additional time spent was 30.00 (20.00, 45.00) minutes. The binary logistic regression analysis showed that after adjusting the relevant factors, the main factors affecting the overall satisfaction rate were the waiting time for making an appointment (the 4- minutes group vs. 8- minutes group: OR=1.863, 95% CI: 1.307-2.657), waiting time for vaccination (the <4 minutes group vs. 8- minutes group: OR=1.529, 95% CI: 1.102-2.120; the 4- minutes group vs. 8- minutes group: OR=1.534, 95% CI: 1.104-2.130), total additional time spent (the 15- minutes group vs. 30- minutes group: OR=1.470, 95% CI: 1.094-1.976). Restricted cubic spline analysis showed that the waiting time for making an appointment (non-linear: χ2=13.18, P=0.001), the waiting time for vaccination (non-linear: χ2=13.50, P=0.001), and the total additional time consumed (non-linear: χ2=9.38, P=0.009) showed a non-linear inverted "V" dose response relationship to the overall satisfaction of vaccination services. Conclusions:The waiting time for parents to make an appointment, the waiting time for vaccination and the total additional time spent for receiving vaccination services affected the overall satisfaction rate of the vaccination services. And the waiting time for making an appointment was the most important factor, and it is necessary to shorten the waiting time for appointment. It is suggested that the vaccination clinic should make use of information technology (such as WeChat public account, APP) to make accurate appointments, make appointments to the time period to control the number of people within time period.

Objective:To understand the time for observation and related factors in the clinics after vaccination among children's parents.Methods:From December 2019 to January 2020, parents of children aged 0-3 years were recruited by multiple-stage sampling from 34 vaccination clinics in 12 districts and counties in 6 provinces (Shandong, Guangdong, Henan, Sichuan, Inner Mongolia, and Liaoning). A questionnaire survey on the time of observation after vaccination was conducted. A multivariate logistic regression model was used to analyze the related factors of parental observation time after vaccination.Results:A total of 3 292 parents of 0-3 year's old children were selected, and 3 178 parents were finally included in the analysis. 87.85%(2 792/3 178) of the parents reported that the observation time after vaccination at clinics was ≥30 minutes. Multivariate logistic regression analysis showed that, after adjusting for the regions, the main factors affecting the observation time at clinics after vaccination among parents appeared as observation time informed by physicians at the clinic appeared ≥30 minutes ( OR=31.622, 95% CI: 19.847-50.384), parents were medical personnel ( OR=2.779, 95% CI: 1.505-5.133), parents being volunteers working on vaccination-related publicity and education activities ( OR=1.986, 95% CI: 1.438-2.743), parents aged 35 years old or above ( OR=1.900, 95% CI: 1.215-2.971), being parents of the first child ( OR=1.663, 95% CI: 1.282-2.156), per capita annual income of the family as 8 000- Yuan ( OR=1.646, 95% CI: 1.168-2.319), children aged 0-12 months old ( OR=1.646, 95% CI: 1.203-2.252) or 13-24 months old ( OR=1.506, 95% CI: 1.064-2.133), obedient to physicians' advice at the clinic ( OR=1.481, 95% CI: 1.067-2.055). Conclusions:The proportions of parents observed for ≥30 minutes at the clinics of vaccination were high. When the information was from the physicians at the vaccination clinic, the observation time was the most critical factor for parents to observe at clinics as required.

Objective: To isolate a bacteriophage against pan-drug resistant Klebsiella pneumoniae in a burn patient, and to study its biological characteristics, genomic information, and effects on bacterial biofilm. Methods: (1) In 2018, pan-drug resistant Klebsiella pneumoniae UA168 (hereinafter referred to as the host bacteria) solution isolated from the blood of a burn patient in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (hereinafter referred to as Ruijin Hospital) was used to isolate and purify the bacteriophage against pan-drug resistant Klebsiella pneumoniae from the sewage of Ruijin Hospital with sewage co-culture method, drip plate method, and double-agar plate method. The bacteriophage was named as phage KP168 and the plaque morphology was observed. (2) The phage KP168 solution was taken for cesium chloride density gradient centrifugation and dialysis, and then the morphology of phage KP168 was observed through transmission electron microscope after phosphotungstic acid negative staining. (3) The phage KP168 solution was taken to determine the lytic ability of the phage KP168 against 20 strains of pan-drug resistant Klebsiella pneumoniae isolated from the burned patients′ blood in Ruijin Hospital by the drip plate method, and then the lysis rate was calculated. (4) The phage KP168 solution at a initial titer of 9.3×10¹¹ plaque-forming unit (PFU)/mL (400 μL per tube) and the host bacteria solution at a concentration of 1×10⁹ colony-forming unit (CFU)/mL (4 mL per tube) were conventionally shaking cultured together for 4 hours at multiplicity of infection (MOI) of 10.000, 1.000, 0.100, 0.010, or 0.001, respectively (1 tube per MOI). The titer of phage KP168 was measured by the double-agar plate method (the measurement method was the same below) to select the optimal MOI. The experiment was repeated three times. (5) The host bacteria solution at a concentration of 1×10⁹ CFU/mL (4 mL per tube) and the phage KP168 solution at an adjusted titer of 5×10⁷ PFU/mL (400 μL per tube) were mixed at the MOI of 0.005. The plaques were counted 0 (immediately), 1, 2, 3, 4, 5, 15, and 30 minutes (1 tube at each time point) after mixing by the double-agar plate method (the counting method was the same below), and the percentage of adsorbed phages was calculated to screen for the optimal adsorption time. The experiment was repeated three times. (6) The host bacteria solution at a concentration of 1×10⁹ CFU/mL (300 μL per tube) and the phage KP168 solution at a titer of 5×10⁸ PFU/mL (60 μL per tube) were mixed at MOI of 0.005 and conventionally shaking cultured after standing for the optimal adsorption time. The phage KP168 titer was measured 0 (immediately), 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 minutes after culture, and a one-step growth curve was drawn. The experiment was repeated three times. (7) The phage KP168 solution at a titer of 2.5×10¹⁰ PFU/mL was left to stand for 1 hour at 37, 40, 50, 60, or 70 ℃ (3 tubes at each time point, 1 mL per tube) for counting the plaques, and then the thermal stability curve was drawn. SM buffer at a pH values of 5.0, 6.0, 7.0, 7.4, 8.0, 9.0, or 10.0 were added to the phage KP168 solution at a titer of 3.0×10¹⁰ PFU/mL, respectively. The mixed solution was left to stand for 1 hour at 37 ℃ (3 tubes of each pH, each tube containing 100 μL phage KP168 solution and 900 μL SM buffer), and then the plaques were counted, and an acid-base stability curve was drawn. (8) The phage KP168 solution was taken for DNA extraction and sequencing after dialysis as in experiment (2). The whole genome was annotated with Prokka to obtain the coding sequence of phage KP168. Nucleotide′s BLAST function was used to proceed nucleic acid sequence alignment for finding a known phage with the highest similarity to the phage KP168 nucleic acid sequence, and Blastx function was used to translate the coding sequence into protein for its function prediction. The comparison with Antibiotic Resistance Genes Database and Virulence Factors Database was proceeded. (9) In a 96-well plate, at a MOI of 1.000, 0.100, 0.010 or 0.001 (3 wells per MOI), 20 μL phage KP168 solution at a initial titer of 5.8×10¹⁰ PFU/mL was added to 200 μL host bacteria solution at a concentration of 1.5×10⁸ CFU/mL (the same concentration below) for co-cultivation for 48 hours. After 200 μL host bacteria solution was left to stand for 48 hours, 20 μL phage KP168 solution at a titer of 1×10^6, 1×10^7, 1×10^8, 1×10^9, or 1×10¹⁰ PFU/mL (3 wells per titer) was added respectively for action for 4 hours. In both experiments, 200 μL host bacteria solution added with 20 μL SM buffer (3 wells) acted as a negative control, and 220 μL LB culture medium (3 wells) acted as a blank control. Absorbance values were measured by a microplate reader, and inhibition/destruction rates of biofilm were calculated. The experiments were both repeated three times. Results: (1) The plaques of phage KP168 successfully isolated and purified were transparent and round, and its diameter was approximately 1.5 mm. (2) The phage KP168 has a regular polyhedron structure with a diameter of about 50 nm and without a tail. (3) The phage KP168 could lyse 13 of 20 strains of Klebsiella pneumoniae from burned patients, with a lysis rate of 65.0%. (4) When MOI was 1.000, the titer was the highest after co-culturing the phage KP168 with the host bacteria for 4 hours, which was the optimal MOI. (5) After the mixing of the phage KP168 with the host bacteria for 4 minutes, the percentage of the adsorbed phage reached the highest, which was the optimal adsorption time. (6) The one-step growth curve showed that during the lysis of the host bacteria by phage KP168, the incubation period was about 10 minutes, and the lysis period was about 40 minutes. (7) With the condition of 40 ℃ or pH 7.4, the number of plaques and the activity of phage KP168 reached the highest. (8) The genome of phage KP168 was a linear double-stranded DNA with a length of 40 114 bp. There were 48 possible coding sequences. It had the highest similarity to Klebsiella phage_vB_Kp1. The most similar known proteins corresponding to the translated proteins of coding sequences contained 23 hypothetical proteins and 25 proteins with known functions. No resistance genes or virulence factor genes were found. The GeneBank accession number was KT367885. (9) After 48 hours of co-cultivation of the phage KP168 and the host bacteria at each MOI, the inhibition rates of biofilm were similar, with an average of about 45%. After the phage KP168 with a titer of 1×10⁹ PFU/mL acted on the biofilm formed by the host bacteria for 4 h, the destruction rate of biofilm was the highest, reaching an average of 42%. Conclusions In this study, a bacteriophage against pan-drug resistant Klebsiella pneumoniae from a burn patient, phage KP168, is isolated from sewage, which belongs to the tailless phage. It has a wide host spectrum, short adsorption time, and short incubation period, with certain thermal and acid-base stability. Its genomic information is clear, and it does not contain resistance genes or virulence factor genes. It also has an inhibitory effect on the formation of bacterial biofilm and a destructive effect on the formed bacterial biofilm.

Objective:To investigate the clinical characteristics of pediatric methicillin-resistant Staphylococcus aureus (MRSA) infection and the antibiotic sensitivity of the isolates. Methods:The clinical data of children with MRSA infection and antibiotic sensitivity of the isolates from 11 children′s hospitals in Infectious Diseases Surveillance of Paediatrics (ISPED) group of China between January 1, 2018 and December 31, 2018 were collected retrospectively. The children′s general condition, high-risk factors, antimicrobial therapy and prognosis, differences in clinical disease and laboratory test results between different age groups, and differences of antibiotic sensitivity between community-acquired (CA)-MRSA and hospital-acquired (HA)-MRSA were analyzed. The t test and Wilcoxon rank sum test were used for statistical analysis of the quantitative data and Chi-square test were used for comparison of rates. Results:Among the 452 patients, 264 were males and 188 were females, aged from 2 days to 17 years. There were 233 cases (51.5%) in the ≤1 year old group, 79 cases (17.5%) in the>1-3 years old group, 29 cases (6.4%) in the >3-5 years old group, 65 cases (14.4%) in the >5-10 years old group, and 46 cases (10.2%) in the>10 years old group. The main distributions of onset seasons were 55 cases (12.2%) in December, 47 cases (10.4%) in February, 46 cases (10.2%) in November, 45 cases (10.0%) in January, 40 cases (8.8%) in March. There were 335 cases (74.1%) CA-MRSA and 117 (25.9%) cases HA-MRSA. Among all cases, 174 cases (38.5%) had basic diseases or long-term use of hormone and immunosuppressive drugs. During the period of hospitalization, 209 cases (46.2%) received medical interventions. There were 182 patients (40.3%) had used antibiotics (β-lactams, glycopeptides, macrolides, carbapenems, oxazolones, sulfonamides etc) 3 months before admission. The most common clinical disease was pneumonia (203 cases), followed by skin soft-tissue infection (133 cases), sepsis (92 cases), deep tissue abscess (42 cases), osteomyelitis (40 cases), and septic arthritis (26 cases), suppurative meningitis (10 cases). The proportion of pneumonia in the ≤1 year old group was higher than the >1-3 years old group,>3-5 years old group,>5-10 years old group,>10 years old group (57.5% (134/233) vs. 30.4% (24/79), 31.0% (9/29), 38.5% (25/65), 23.9% (11/46), χ 2=17.374, 7.293, 7.410, 17.373, all P<0.01) The proportion of skin and soft tissue infections caused by CA-MRSA infection was higher than HA-MRSA (33.4% (112/335) vs. 17.9% (21/117), χ 2=10.010, P=0.002), and the proportion of pneumonia caused by HA-MRSA infection was higher than CA-MRSA (53.0% (62/117) vs. 42.1% (141/335), χ 2=4.166, P=0.041). The first white blood cell count of the ≤1 year old group was higher than that children > 1 year old ((15±8)×10 9/L vs. (13±7)×10 9/L, t=2.697, P=0.007), while the C-reactive protein of the ≤1 year old group was lower than the 1-3 years old group,>5-10 years old group,>10 years old group (8.00 (0.04-194.00) vs.17.00 (0.50-316.00), 15.20 (0.23-312.00), 21.79(0.13-219.00) mg/L, Z=3.207, 2.044, 2.513, all P<0.05), there were no significant differences in procalcitonin (PCT) between different age groups (all P>0.05). After the treatment, 131 cases were cured, 278 cases were improved, 21 cases were not cured, 12 cases died, and 10 cases were abandoned. The 452 MRSA isolates were all sensitive to vancomycin (100.0%), linezolid (100.0%), 100.0% resistant to penicillin, highly resistant to erythromycin (85.0%, 375/441), clindamycin (67.7%, 294/434), less resistant to sulfonamides (5.9%, 23/391), levofloxacin (4.5%, 19/423), gentamicin (3.2%, 14/438), rifampicin (1.8%, 8/440), minocycline (1.1%, 1/91). The antimicrobial resistance rates were not significantly different between the CA-MRSA and HA-MRSA groups (all P>0.05). Conclusions:The infection of MRSA is mainly found in infants under 3 years old. The prevalent seasons are winter and spring, and MRSA is mainly acquired in the community. The main clinical diseases are pneumonia, skin soft-tissue infection and sepsis. No MRSA isolate is resistant to vancomycin, linezolid. MRSA isolates are generally sensitive to sulfonamides, levofloxacin, gentamicin, rifampicin, minocycline, and were highly resistant to erythromycin and clindamycin. To achieve better prognosis. clinicians should initiate anti-infective treatment for children with MRSA infection according to the clinical characteristics of patients and drug sensitivity of the isolates timely and effectively.