[Inhibitory effect of small-molecule compound AM679 targeting elongation-factor binding protein 2 on hepatitis B virus in vitro].

Objective: To explore the antiviral activity of the small-molecule compound AM679 in hepatitis B virus (HBV) replication and infection cell models. Methods: The positive regulatory effect of AM679 on EFTUD2 expression was validated by qPCR and Western blotting. HepAD38 and HepG2-NTCP cells were treated with AM679 (0.5, 1, and 2 nmol/L). Negative control, positive control, and AM679 combined with the entecavir group were set up. HBV DNA intra-and extracellularly, as well as the expression levels of intracellular HBV total RNAs and 3.5kb-RNA changes, were detected with qPCR. Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) levels were measured in the cell supernatant by an enzyme-linked immunosorbent assay (ELISA). The t-test method was used for the statistical analysis of the mean difference between groups. Results: EFTUD2 mRNA and protein expression levels were significantly increased in HepAD38 and HepG2-NTCP cells following AM679 treatment, with a statistically significant difference (P < 0.001). Intra-and extracellular indicators such as HBV DNA, HBV RNAs, HBV 3.5kb-RNA, HBsAg, and HBeAg were decreased to varying degrees in both cell models, and the decrease in these indicators was more pronounced with the increase in AM679 concentration and prolonged treatment duration, while the combined use of AM679 and entecavir had a more significant antiviral effect. The HBV DNA inhibition rates in the supernatant of HepAD38 cells with the use of 2 nmol/L AM679 were 21% and 48% on days three and nine, respectively. The AM679 combined with the ETV treatment group had the most significant inhibitory effect (62%), with a P < 0.01. More active HBV replication was observed after silencing EFTUD2, while the antiviral activity of AM679 was significantly weakened. Conclusion: AM679 exerts anti-HBV activity in vitro by targeting the regulation of EFTUD2 expression.

[A survey on the implementation of cardiovascular surgery for congenital heart disease in China between 2017 and 2021].

Objective: To investigate the inplementation of cardiovascular surgery for congenital heart disease (CHD) in China. Methods: A cross-sectional study was carried out. The CHD cardiovascular surgery data collected by the Chinese Society of Extracorporeal Circulation from 2017 to 2021 in 31 provinces (autonomous regions/municipalities) of China were retrospectively reviewed, the implementation of CHD cardiovascular surgery in different provinces, regions, general/specialized hospitals, and different age groups (whether≤18 years old) were summarized, and the correlation analysis between the number of surgeries carried out in each province/region and the gross regional product and the number of the regional population was performed. Results: Between 2017 and 2021, the annual volume of CHD cardiovascular surgery was 77 120, 77 634, 81 161, 62 663 and 71 492, respectively, showing a decreasing trend. Meanwhile, the proportion of CHD patients aged≤18 years who underwent cardiovascular surgery also showed a downward trend, from 79.8% (61 557/77 120) in 2017 to 58.6% (41 871/71 492) in 2021 (P=0.027). The number of surgical cases varied greatly among different provinces, including 4 provinces with≥5 000 cases and 9 provinces with 2 000-5 000 cases. In the five years, the number of CHD cardiovascular surgeries in Central and East China was the largest, accounting for 41.1%-45.5% of the total surgical cases. The proportion of CHD surgery cases≤18 years old was the highest in Southwest China (69.7%-87.4%) and the lowest in Northeast China (28.2%-68.9%). Except for 2021, the number of cases carried out by each region between 2017 and 2020 was correlated with the gross regional product (r=0.929, 0.929, 0.893 and 0.964, respectively, all P<0.05) and the population (r=0.821, 0.893, 0.821 and 0.857, respectively, all P<0.05). Hospitals that performed more than 100 operations (20.5%±1.2% of the total number of hospitals) completed 86.2%±1.2% of the total number of operations in China during the 5-year period. In 2017 and 2021, the number of CHD cardiovascular surgeries preformed in children's/women's and children's specialized hospitals accounted for 24.3% (18 772/77 120) and 23.8% (17 012/71 492) of the total number of cases in China, respectively. Conclusions: From 2017 to 2021, the number of cardiovascular surgery for CHD decreases slightly, but the proportion of surgery for adult CHD patients increases significantly.There is a strong correlation between the number of CHD operations in each region and their economic development status. The scale of CHD cardiovascular surgery performed in children's hospitals/women's and children's hospitals accounts for about a quarter of the total volume in China.

[Clinical characteristics of pertussis in hospitalized children under 3 months].

Demographic data and clinical data were collected retrospectively from patients with pertussis at the Children's Hospital Affiliated to the Capital Institute of Pediatrics between March 2011 and February 2023. Among the 270 hospitalized patients, 151 cases were male and 119 were female. The youngest age of admission was 10 days and the eldest age of admission was 11 years. The 270 hospitalized patients were divided into two groups according to onset age: <3 months (n=143) and≥3 months (n=127). For those in the <3-month-old group, the incidence of severe pneumonia and severe pertussis were 21.0% and 38.5%, respectively, both were significantly higher than those in≥3-month-old group (7.9% and 11.0%, both P<0.05). For those in the <3-month-old group, paroxysmal spasmodic cough, post-tussive vomiting, paroxysmal cyanosis, apnea, and decreased heart rate after coughing were 86.7%, 25.2%, 38.5%, 7.0% and 16.8%, respectively, all were significantly higher than those in ≥3-month-old group (76.4%, 10.2%, 15.7%, 1.6% and 1.6%, all P<0.05). For those in the<3-month-old group, the incidence of hypoxemia, respiratory failure, were 36.4%, 16.8%, respectively, and both were significantly higher than those in≥3-month-old group (10.2%, 7.1%, P<0.05). It indicated that among the infants under 3 months, the incidence of vomiting after coughing, paroxysmal cyanosis, apnea, hypoxemia, respiratory failure, decreased heart rate after coughing and severe pneumonia were significantly higher than those above 3 months. Infants under 3 months were prone to severe pertussis.

[Research on the framework of biosafety standards for pathogenic microbial laboratories].

Developing and implementing biosafety standards for pathogenic microbiology laboratories is essential to achieving scientific, efficient, and standardized management and operation. This article analyzes the current standardization construction in biosafety in pathogenic microbiology laboratories domestically and internationally. It proposes a framework for the biosafety standard system of pathogenic microbiology laboratories, which mainly includes four parts: basic standards, management standards, technical standards, and industry applications. It provides a reference for the standardization work of pathogenic microbiology laboratories and helps to standardize the biosafety industry in China.

Remnant cholesterol is associated with hip BMD and low bone mass in young and middle-aged men: a cross-sectional study.

PURPOSE: Remnant cholesterol (RC) is a contributor to cardiovascular diseases, obesity, diabetes, and metabolic syndrome. However, the specific relationship between RC and bone metabolism remains unexplored. Therefore, we aimed to investigate the relationships of RC with hip bone mineral density (BMD) and the risk of low bone mass. METHODS: Physical examination data was collected from men aged < 60 years as part of the Kailuan Study between 2014 and 2018. The characteristics of the participants were compared between RC quartile groups. A generalized linear regression model was used to evaluate the relationship between RC and hip BMD and a logistic regression model was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for low bone mass. Additional analyses were performed after stratification by body mass index (BMI) (≥ or < 24 kg/m2). Sensitivity analyses were performed by excluding individuals who were taking lipid-lowering therapy or had cancer, cardiovascular diseases, or diabetes. RESULTS: Data from a total of 7,053 participants were included in the analysis. After adjustment for confounding factors, RC negatively correlated with hip BMD (ß = - 0.0079, 95% CI: - 0.0133, - 0.0025). The risk of low bone mass increased from the lowest to the highest RC quartile, with ORs of 1 (reference), 1.09 (95% CI: (0.82, 1.44), 1.35 (95%CI: 1.02, 1.77), and 1.43 (95% CI: 1.09, 1.89) for Q1, Q2, Q3, and Q4, respectively (P for trend = 0.004) in the fully adjusted model. Compared to RC < 0.80 mmol/l group, the risk of low bone mass increased 39% in RC ≥ 0.80 mmol/l group (P < 0.001). The correlation between RC and hip BMD was stronger in participants with BMI ≥ 24 kg/m2 group (ß = - 0.0159, 95% CI: - 0.0289, - 0.0029). The results of sensitivity analyses were consistent with the main results. CONCLUSION: We have identified a negative correlation between serum RC and hip BMD, and a higher RC concentration was found to be associated with a greater risk of low bone mass in young and middle-aged men.

New insights on the association of weight loss with the reduction in carotid intima-media thickness among patients with obesity: an updated systematic review and meta-analysis.

OBJECTIVES: Carotid intima-media thickness (CIMT) is a noninvasive marker of atherosclerosis, a typical pathologic process underlying cardiovascular diseases (CVDs). It is essential to explore the relationships between weight loss and the reduction of CIMT. STUDY DESIGN: This was an updated systematic review and meta-analysis. METHODS: A systematic literature search was conducted to collect relevant clinical trials. The pooled results of meta-analyses were assessed by weighted mean difference (WMD) and the corresponding 95 % confidence interval (95% CI). RESULTS: Thirty-three articles involving 2273 participants were collected in this meta-analysis. Among all participants with obesity, the pooled mean of weight loss was -23.26 kg (95% CI: -27.71 to -18.81), and the pooled mean change of CIMT was -0.06 mm (95% CI: -0.08 to -0.04). Compared with Non-surgical interventions, Surgical ones could lead to much higher weight loss (Pbetween groups < 0.001). A more significant CIMT reduction was identified among Surgical intervention patients than among Non-surgical intervention participants (Pbetween groups < 0.001). CONCLUSIONS: Effective interventions, especially Surgical interventions, could reduce the weight of patients with obesity, followed by the decline of CIMT, which might further disturb atherosclerosis progression and lower CVD risk.

The effect of previous orbital decompression on outcomes of rectus muscle recession surgery in patients with thyroid ophthalmopathy.

PURPOSE: To evaluate the effect of previous orbital decompression on outcomes of rectus muscle recession surgery in patients with thyroid-associated ophthalmopathy. METHODS: This retrospective study enrolled 55 eyes of 33 patients treated in our hospital for restrictive strabismus caused by thyroid-associated ophthalmopathy. We performed muscle recession for the obviously restricted extraocular muscles, with 6 weeks of follow-up. Surgical outcomes were compared between the orbital decompression group (DG, n=15) and non-orbital decompression group (NDG, n=18). RESULTS: A total of 33 patients with Graves' ophthalmopathy who underwent rectus muscle recession surgery were included. Of these, 15 patients had undergone orbital decompression prior to strabismus surgery, and 18 had not. The two groups did not differ in terms of the preoperative horizontal or vertical ocular deviation, degree of restriction of eye movement, degree of diplopia, or mean number of muscles that underwent surgery (P>0.05). There was no significant difference in the preoperative horizontal or vertical ocular deviation, level of eye movement restriction, degree of diplopia and the success rate of the surgery (P>0.05). CONCLUSION: Rectus muscle recession surgery in patients with thyroid-associated ophthalmopathy during the quiescent period could improve the ocular deviation and diplopia, and orbital decompression performed before strabismus surgery had no significant effect on surgical technique or outcomes of rectus muscle recession surgery.

Sorption behaviour of neptunium in marine and fresh water bottom sediments in Far East area of Russia (Lake Khanka and Amur Bay).

The concentration and sorption behavior of 237Np on the bottom sediments of water bodies in the Far East region of Russia (Lake Khanka and Peter the Great Bay) were studied for the first time. The 237Np concentrations vary from 1.06 × 10-6 to 4.43 × 10-5 mBq g-1 in the bottom sediments of Lake Khanka and from 1.05 × 10-4 to 2.52 × 10-3 mBq g-1 for Amur Bay. The experiment on the adsorption of Np on marine and lake sediment showed that it is sorbed through complexation with silicates (albite, leucite). The Np sorption isotherm on marine sediments is described by the Langmuir equation; the distribution coefficients (Kd) of Np vary from 57 to 588 mL g-1. For lake sediments, the isotherm is described by the Henry equation; the Kd value reaches 935 mL g-1.

[Budd-Chiari syndrome with hepatopulmonary syndrome: a case report and literature review].

Objective: To summarize the clinical features and prognosis of Budd-Chiari syndrome with hepatopulmonary syndrome (HPS) in children. Methods: The clinical data of a child who had Budd-Chiari syndrome with HPS treated at the Department of Pediatrics of the First Affiliated Hospital of Zhengzhou University in December 2016 was analyzed retrospectively. Taking "Budd-Chiari syndrome" and "hepatopulmonary syndrome" in Chinese or English as the keywords, literature was searched at CNKI, Wanfang, China Biomedical Literature Database and PubMed up to July 2023. Combined with this case, the clinical characteristics, diagnosis, treatment and prognosis of Budd-Chiari syndrome with HPS in children under the age of 18 were summarized. Results: A 13-year-old boy, presented with cyanosis and chest tightness after activities for 6 months, and yellow staining of the skin for 1 week. Physical examination at admission not only found mild yellow staining of the skin and sclera, but also found cyanosis of the lips, periocular skin, and extremities. Laboratory examination showed abnormal liver function with total bilirubin 53 µmol/L, direct bilirubin 14 µmol/L, and indirect bilirubin 39 µmol/L, and abnormal blood gas analysis with the partial pressure of oxygen of 54 mmHg (1 mmHg=0.133 kPa), the partial pressure of carbon dioxide of 31 mmHg, and the alveolar-arterial oxygen gradient of 57 mmHg. Hepatic vein-type Budd-Chiari syndrome, cirrhosis, and portal hypertension were indicated by abdominal CT venography. Contrast-enhanced transthoracic echocardiography (CE-TTE) was positive. After symptomatic and supportive treatment, this patient was discharged and received oxygen therapy outside the hospital. At follow-up until March 2023, there was no significant improvement in hypoxemia, accompanied by limited daily activities. Based on the literature, there were 3 reports in English while none in Chinese, 3 cases were reported. Among a total of 4 children, the chief complaints were dyspnea, cyanosis, or hypoxemia in 3 cases, and unknown in 1 case. There were 2 cases diagnosed with Budd-Chiari syndrome with HPS at the same time due to respiratory symptoms, and 2 cases developed HPS 1.5 years and 8.0 years after the diagnosis of Budd-Chiari syndrome respectively. CE-TTE was positive in 2 cases and pulmonary perfusion imaging was positive in 2 cases. Liver transplantation was performed in 2 cases and their respiratory function recovered well; 1 case received oxygen therapy, with no improvement in hypoxemia; 1 case was waiting for liver transplantation. Conclusions: The onset of Budd-Chiari syndrome with HPS is insidious. The most common clinical manifestations are dyspnea and cyanosis. It can reduce misdiagnosis to confirm intrapulmonary vascular dilatations with CE-TTE at an early stage. Liver transplantation is helpful in improving the prognosis.

[Association between remnant cholesterol levels and incident diabetic retinopathy in middle-aged and older patients with diabetes].

Objective: To investigate the association between remnant cholesterol (RC) and the risk of diabetic retinopathy (DR) in middle-aged and older individuals with diabetes. Methods: Based on the Shanghai Nicheng Cohort Study database, the data of 1 255 individuals with diabetes aged 55-70 years at baseline (2013-2014) with complete fundus photographs and serum cholesterol data in Nicheng, Shanghai, were analyzed. Multinomial logistic regression models were used to evaluate risk ratios (RRs) and their 95% confidence intervals (CIs) between baseline RC level and incident DR. Results: The median age of the subjects was 61.9 years, and 60.4% were women. After a 4.6-year follow-up, 79 (6.3%) patients developed DR, including 50 (4.0%) mild non-proliferative DR and 29 (2.3%) referable DR (RDR). Multivariable logistic regression showed that each mmol/L increase of RC was associated with a 40% higher risk of RDR (RR=1.40, 95%CI 1.03-1.90). Compared with the lowest tertile of RC (<0.63 mmol/L), the risk of RDR in the highest tertile (≥0.85 mmol/L) increased by 4.59 times (RR=5.59, 95%CI 1.51-20.73). Conclusion: The RC level may help identify individuals at high risk of incident RDR in middle-aged and older Chinese adults with diabetes.

[Risk analysis of gastrointestinal bleeding in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention].

Objective: Of all spontaneous bleeding complications in patients with acute ST-elevation myocardial infarction (STEMI), upper gastrointestinal bleeding (UGIB) is the most common and of specific interest, because it can be prevented by several prophylactic measures. The purpose of this study was to investigate the in-hospital incidence, associated outcomes, and predictors of UGIB after STEMI. Methods: In this retrospective study, we analyzed the records of 2 791 patients with acute STEMI admitted to Beijing Anzhen Hospital Affiliated to Capital Medical University between January 2018 and January 2022. The patients were divided into the UGIB group (n=61) and non-UGIB group (n=2 730) according to the presence or absence of upper gastrointestinal hemorrhage, respectively. Baseline clinical conditions, coronary lesions, in-hospital deaths, and in-hospital adverse events were compared between the two groups. Logistic regression analysis was also performed for risk factors that could lead to UGIB. Results: The in-hospital incidence of UGIB after STEMI was 2.2% (61/2 791). Hospital stay was significantly longer in the UGIB group [8(6, 12) days vs. 5 (4, 7) days, Z=3.28, P<0.001] and in-hospital mortality was significantly higher in the UGIB group than in the non-UGIB group (9.8% vs. 0.8%, χ2=0.63, P=0.001). Patients with UGIB were significantly older than those without UGIB (63±11 years vs. 58±11 years, t=-3.75, P<0.001). The serum creatinine level of UGIB patients was significantly higher than that of non-UGIB patients [(80(62, 98) mmol/L vs. 73(64, 84) mmol/L, Z=1.68, P=0.007], the red blood cell count of UGIB patients was significantly lower than that of non-UGIB patients [4.1(3.8, 4.6)×1012/L vs. 4.6(4.2, 4.9)×1012/L, Z=2.61,P<0.001], and the hemoglobin concentration of UGIB patients was significantly lower than that of non-UGIB patients [129(109, 141) g/L vs. 141(130, 152) g/L, Z=2.52,P<0.001]. Brain natriuretic peptide levels were significantly higher in UGIB patients than in non-UGIB patients [331(165, 644) ng/L vs. 181(89, 333) ng/L, Z=2.42,P<0.001]. Logistic regression analysis showed that age (OR=1.045, 95%CI 1.009-1.082, P=0.013); hemoglobin (OR=1.594, 95%CI 1.150-2.210, P=0.005); hematocrit (OR=0.181, 95%CI 0.060-0.546, P=0.002); and mean hemoglobin concentration (OR=0.845, 95%CI 0.752-0.951, P=0.005) were independent risk factors for UGIB in patients with STEMI. Logistic regression analysis of risk factors for in-hospital death revealed that concurrent UGIB was an independent risk factor for in-hospital death in patients with STEMI (OR=2.954, 95%CI 0.635-13.751, P=0.024). Conclusions: The incidence of in-hospital UGIB in STEMI patients was 2.2%, and the in-hospital mortality rate of STEMI complicated with UGIB increased to 9.8%. Concurrent UGIB was an independent risk factor for in-hospital death in patients with STEMI. The most important predictors of in-hospital UGIB in patients with STEMI were age, hemoglobin, hematocrit, and mean hemoglobin concentration.

[Progress in research of epidemiology of relapsing fever and prevention and control measures].

Relapsing fever, caused by Borreliae of the relapsing fever groups, is an infectious disease, which would cause spirochaetaemia and repeated fever in human. To comprehensively understand the classification and distribution of relapsing fever, as well as correlated factors, this paper summarizes the progress in research of epidemiology of relapsing fever in the world, and suggests prevention and control measures. The disease is heterogenous and can be divided into three groups according to vectors, i.e. tick-borne relapsing fever, louse-borne relapsing fever and the avian relapsing fever. Tick borne relapsing fever can be further divided into two types: soft tick transmission and hard tick transmission. Soft tick-borne relapsing fever generally has obvious geographical distribution characteristics, while hard tick-borne relapsing fever is widely distributed all over the world. Louse-borne relapsing fever, also known as epidemic forms of relapsing fever, is caused by body lice, and the incidence is usually associated with war, famine, refugees and poor sanitation. The prevention and control of relapsing fever should be based on local conditions.

[Development of extracorporeal circulation in China].

Reviewing the 65-year development since 1958, extracorporeal circulation (ECC) in China, which experienced different stages of exploration, growth, maturity and development, has gradually matured. Cardiovascular surgery under ECC has been promoted throughout the country with an increasing rate of success. Furthermore, the derived extracorporeal membrane oxygenation (ECMO) has developed greatly in the field of critical care. In the future, China's ECC will further strengthen professional standardization under the guidance of the "personalized" precision treatment concept, and will make greater contributions to the nation's health.

[Myocardial protection of del Nido cardioplegia in adult cardiac and major vascular surgery with long aortic cross-clamp time].

Objective: To explore the safety and myocardial protection efficacy of del Nido cardioplegia in adult cardiac and major vascular surgery with long aortic cross-clamp (ACC) time. Methods: A total of 2 536 patients who underwent adult cardiac and major vascular surgery with ACC time>90 min at Beijing Anzhen Hospital from March 2018 to March 2023 were collected. The patients were divided into two groups according to the type of cardioplegia solution: the del Nido cardioplegia solution group (DC group) and the cold blood cardioplegia solution group (BC group). Preoperative baseline data of the patients (age, gender, comorbidities, ejection fraction, etc) were adjusted using propensity score matching (PSM). Cardiopulmonary bypass (CPB) time, ACC time, total amount of cardioplegia solution, in-hospital mortality rate, length of intensive care unit (ICU) stay, mechanical ventilation time, postoperative complications, left ventricular ejection fraction, and troponin levels were compared between the two groups. Results: After PSM, a total of 306 patients were included, including 223 males and 83 females, with a mean age of (52.0±12.3) years. There were 153 cases in the DC group and 153 cases in the BC group. Compared with the DC group, the cross-clamp time was longer [109(100, 150) min vs 102(91, 133) min, P<0.001], the rate of return to spontaneous rhythm was lower [51.6% (79/153) vs 86.9%(133/153), P<0.001], and intraoperative peak glucose was higher [12.6 (6.5, 15.9) mmol/L vs 10.1 (8.5, 12.4) mmol/L, P=0.005] in the BC group. In addition, perioperative mortality [4.6% (7/153) vs 3.3% (5/153), P=0.132], stroke[3.9% (6/153) vs 3.3% (5/153), P=0.759], renal insufficiency [3.3% (5/153) vs 6.5% (10/153), P=0.186], atrial fibrillation [4.6% (7/153) vs 2.6% (4/153), P=0.652] and low cardiac output syndrome [3.9% (6/153) vs 4.6% (7/153), P=0.716] did not differ between the two groups. Compared with BC group, DC group had lower level of high sensitivity troponin (hsTnI) [1.2 (0.8, 1.8) µg/L vs 1.3 (0.9, 2.3) µg/L, P=0.030] and creatine kinase isoenzyme (CK-MB) [31.0 (20.0, 48.9) µg/L vs 37.0 (24.0, 58.9) µg/L, P=0.011] at 24 h postoperatively, and shorter length of ICU stay [35.6 (19.8, 60.5) h vs 42.6 (21.9, 83.6) h, P=0.015] and mechanical ventilation time [20.5 (15.5, 41.0) h vs 31.5 (17.1, 56.0) h, P=0.012]. Subgroup analysis showed that in the 120-180 minute subgroup, patients in the DC group had a shorter cross-clamp time [132 (124, 135) min vs 136 (124, 138) min, P<0.001], while levels of hsTnI [1.6 (1.1, 2.0) µg/L vs 1.4 (1.0, 2.6) µg/L, P=0.030] and CK-MB [38.8 (23.5, 55.5) µg/L vs 37.0 (24.5, 62.3) µg/L, P=0.011] were higher than those in the BC group. Conclusions: In adult cardiac and major vascular surgery with ACC times>90 min, comparable myocardial protection is observed with the use of DC compared with BC. Additional advantages in glycemic control, return to spontaneous rhythm, and improved surgical procedures make DN an attractive alternative for myocardial protection in adult cardiac surgery.

[Quality of blood smear examinations for malaria parasites in Chenzhou City after malaria elimination].

OBJECTIVE: To analyze the quality of blood smear examinations for malaria parasites in Chenzhou City, so as to provide insights into sustainable consolidation of malaria elimination achievements. METHODS: All positive blood smears from fever patients were irregularly sampled from each county (district) of Chenzhou City from 2018 to 2022 and reexamined, and no less than 3% negative blood smears were reexamined. The preparation, dyeing, cleanliness and microscopic examination results of blood smear were reexamined, and the quality of blood smear reexaminations was assessed using a descriptive statistical method. RESULTS: A total of 13 625 fever patients received blood smear examinations for malaria parasites in Chenzhou City from 2018 to 2022, of which 21 were positive and 13 604 were negative; 687 blood samples were reviewed, and the percentage of negative blood smear reexaminations was 4.90% (666/13 604), with a 63.51% rate of qualified negative blood smears preparation, a 67.87% rate of qualified dyeing and a 76.13% rate of qualified cleanliness, and no missing diagnosis found. There were 21 positive blood smears reexamined, and the proportions of qualified blood smears preparation, dyeing and cleanliness were all 85.71%, with 2 smears mistaking Plasmodium species (9.52%). The percentage of qualified negative blood smears preparation was 51.41% in 2022, which reduced by 31.61% in relative to that (75.17%) in 2019 (χ2 = 9.033, P < 0.05), and the percentage of qualified negative blood smears dyeing was 60.19% in 2022, which reduced by 28.82% in relative to that (84.56%) in 2019 (χ2 = 19.498, P < 0.05), while the percentage of qualified negative blood smears cleanliness was 62.96% in 2022, which reduced by 28.93% in relative to that (88.59%) in 2019 (χ2 = 23.826, P < 0.001). In addition, there were no significant differences in the proportion of qualified negative blood smears preparation (χ2 = 0.260, P > 0.05) or dyeing (χ2 = 1.094, P > 0.05) among the three years, while a significant difference was detected in the percentage of qualified negative blood smears cleanliness (χ2 = 12.175, P < 0.05). CONCLUSIONS: No missing diagnosis was seen in blood smear examinations for malaria parasites among fever patients in Chenzhou City after malaria elimination; however, there were reductions in proportions of qualified blood smears preparation, dyeing and cleanliness. Quality control of blood smear examinations is recommended to be reinforced in key regions of Chenzhou City.