Serotype distribution and antimicrobial resistance of pediatric Streptococcus pneumoniae isolated from inpatients and outpatients at Beijing Children's Hospital.

BACKGROUND: Understanding the epidemiology of Streptococcus pneumoniae (S. pneumoniae) isolates is important for pneumonia treatment and prevention. This research aimed to explore the epidemiological characteristics of S. pneumoniae isolated from pediatric inpatients and outpatients during the same period. METHODS: S. pneumoniae were isolated from unsterile samples of inpatients and outpatients younger than five years old between March 2013 and February 2014. The serotypes were determined using diagnostic pneumococcal antisera. The resistance of each strain to 13 antibiotics was tested using either the E-test or the disc diffusion method. The Sequence Types (STs) were analyzed via Multilocus Sequence Typing (MLST). RESULTS: The dominant serotypes obtained from inpatients were 19F (32.9 %), 19A (20.7 %), 23F (10.7 %), 6A (10.0 %), and 14 (8.6 %), while those from outpatients were 19F (13.6 %), 23F (12.9 %), 6A (10.0 %), 6B (10.0 %), and 19A (7.9 %). The coverage rates of 13-valent Pneumococcal Conjugate Vaccine (PCV) formulations were high in both groups. The nonsusceptibility to penicillin, cefuroxime, imipenem, erythromycin, and trimethoprim-sulfamethoxazole among the inpatient isolates was 7.1 %, 92.8 %, 65.7 %, 100 %, and 85.0 %, respectively, while that among the outpatient isolates was 0.7 %, 50.0 %, 38.6 %, 96.4 %, and 65.7 %, respectively. There were 45 and 81 STs detected from the pneumococci isolated from inpatients and outpatients, respectively. CC271 was common among both inpatients and outpatients (43.6 % and 14.3 %). CONCLUSIONS: Pneumococcal vaccine-related serotypes are prevalent among both inpatients and outpatients, especially among inpatients, who exhibit more severe antibiotic resistance. Therefore, universal immunization with PCV13 would decrease the hospitalization rate due to S. pneumoniae and the antibiotic resistance rate of S. pneumoniae.

[Research progress on the mechanism of -lactam resistance in group A Streptococci in vivo]. / Aæ—é“¾çƒèŒä½“å† è€å—-å† é °èƒºç±»è¯ç‰©çš„æœºåˆ¶ç ”ç©¶è¿›å±•.

-lactams, including penicillin, have been used for over 80 years in the treatment of group A Streptococcus (GAS) infections. Although -lactam-resistant GAS strains have not been identified in vitro tests, clinical treatment failures have been reported since the 1950s. The mechanism underlying the clinical failure of -lactam treatment in GAS infections remains unclear. Previous research has suggested that -lactam resistance in GAS in vivo is associated with reduced drug susceptibility of strains, bacterial inoculation effects, biofilm formation, the effect of coexisting bacteria, bacterial persistence, and bacterial internalization into host cells. This article reviews the main reports on -lactam treatment failure in GAS infections and analyzes the possible mechanisms of -lactam resistance in vivo. The findings aim to contribute to future research and clinical approaches in the field.

Novel antibacterial drug target against Gram-negative bacteria: lipopolysaccharide transport protein LptDE and its inhibitors / 药学学报

The outer membrane composed predominantly of lipopolysaccharide (LPS) is an essential biological barrier for most Gram-negative (G-) bacteria. Lipopolysaccharide transport protein (Lpt) complex LptDE is responsible for the critical final stage of LPS transport and outer membrane assembly. The structure and function of LptDE are highly conserved in most G- bacteria but absent in mammalian cells, and thus LptDE complex is regarded as an attractive antibacterial target. In recent 10 years, the deciphering of the three-dimensional structure of LptDE protein facilities the drug discovery based on such "non-enzyme" proteins. Murepavadin, a peptidomimetic compound, was reported to be the first compound able to target LptD, enlightening a new class of antibacterial molecules with novel mechanisms of action. This article is devoted to summarize the molecular characteristics, structure-function of LptDE protein complex and review the development of murepavadin and related peptidomimetic compounds, in order to provide references for relevant researches.

Advances of metabolomics in ocular diseases / 国际眼科杂志(Guoji Yanke Zazhi)

Ocular diseases pose a significant challenge to global health. The field of metabolomics, which involves the systematic identification and quantification of metabolites within a biological system, has emerged as a promising research approach for unraveling disease mechanisms and discovering novel biomarkers. Through its application, metabolomics has yielded valuable knowledge pertaining to the initiation and advancement of various ocular diseases. This review presents an overview of metabolomics and examines recent research progess in four ocular diseases, specifically diabetic retinopathy, age-related macular degeneration, glaucoma, and dry eye, summarizing potential biomarkers and metabolic pathways associated with these diseases. Additionally, this review offers insights into the future prospects of utilizing metabolomics for the management and treatment of ocular diseases.

Research progress on the mechanism of -lactam resistance in group A Streptococci in vivo / 中国当代儿科杂志

-lactams, including penicillin, have been used for over 80 years in the treatment of group A Streptococcus (GAS) infections. Although -lactam-resistant GAS strains have not been identified in vitro tests, clinical treatment failures have been reported since the 1950s. The mechanism underlying the clinical failure of -lactam treatment in GAS infections remains unclear. Previous research has suggested that -lactam resistance in GAS in vivo is associated with reduced drug susceptibility of strains, bacterial inoculation effects, biofilm formation, the effect of coexisting bacteria, bacterial persistence, and bacterial internalization into host cells. This article reviews the main reports on -lactam treatment failure in GAS infections and analyzes the possible mechanisms of -lactam resistance in vivo. The findings aim to contribute to future research and clinical approaches in the field.

[Recent research on the epidemiology and preventive strategies of neonatal group B Streptococcus infection in the latest decade]. / 新生儿Bæ—é“¾çƒèŒæ„ŸæŸ“æµè¡Œç— å­¦å’Œé¢„é˜²ç­–ç•¥è¿‘åå¹´æ¥çš„ç ”ç©¶è¿›å±•.

Currently, the main strategy for preventing neonatal group B Streptococcus (GBS) infection is prenatal screening combined with intrapartum antibiotic prophylaxis, which has effectively reduced the incidence of neonatal GBS early-onset disease. However, the burden of GBS infection is still significant. The intrapartum antibiotic prophylaxis strategy has limitations such as inducing antibiotic resistance and inability to effectively prevent GBS late-onset disease. It is crucial to develop and evaluate other prevention strategies, while paying close attention to assessing penicillin allergy in pregnant women and how to prevent GBS infection in neonates with negative maternal GBS screening. In recent years, there has been some progress in GBS vaccines and related immunological research, and the use of specific vaccines is expected to significantly reduce GBS infection in neonates.

[Paying attention to the epidemic of group A Streptococcus infections in multiple European and American countries]. / å ³æ³¨æ¬§ç¾Žå¤šå›½Aæ—é“¾çƒèŒæ„ŸæŸ“ç–«æƒ .

At the end of 2022, the World Health Organization reported an increase in group A Streptococcus (GAS) infections, such as scarlet fever, in multiple countries. The outbreak primarily affected children under 10 years old, and the number of deaths was higher than anticipated, causing international concern. This paper reviews the current state of the GAS disease outbreak, its causes, and response measures. The authors aim to draw attention from clinical workers in China and increase their awareness and vigilance regarding this epidemic. Healthcare workers should be aware of the potential epidemiological changes in infectious diseases that may arise after the optimization of control measures for coronavirus disease 2019 to ensure children's health.

The dynamic change of serotype distribution and antimicrobial resistance of pneumococcal isolates since PCV13 administration and COVID-19 control in Urumqi, China.

Objective: This study aims to analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from children aged 8 days to 7 years in Urumqi, China, between 2014 to 2021, during which PCV13 was introduced in the private sector's immunization program and COVID-19 control was administrated in the last 2 years. Methods: Serotypes of S. pneumoniae isolates were determined by Quellung reaction, and their susceptibility against 14 antimicrobials were tested. According to the start year of PCV13 administration (2017) and COVID-19 control (2020), the study period was divided into three stages: 2014-2015, 2018-2019, and 2020-2021. Results: A total of 317 isolates were involved in this study. The most common serotypes were type 19F (34.4%), followed by 19A (15.8%), 23F (11.7%), 6B (11.4%), and 6A(5.0%). The coverage rate of both PCV13 and PCV15 was 83.0%. The coverage of PCV20 was a little higher at 85.2%. The resistance rate against penicillin was 28.6% according to the breakpoints of oral penicillin, which would reach up to 91.8% based on the breakpoints of parenteral penicillin for meningitis. The resistance rates to erythromycin, clindamycin, tetracycline, and sulfamethoxazole-trimethoprim were 95.9%, 90.2%, 88.9%, and 78.8%, respectively. The PCV13 isolate was more resistant to penicillin than the non-PCV13 ones. There was not any significant change found in the serotype distribution since the PCV13 introduction and the COVID-19 control. The resistance rate against oral penicillin slightly elevated to 34.5% in 2018-2019 from 30.7% in 2014-2015 and then decreased significantly to 18.1% in 2020-2021 (χ 2 = 7.716, P < 0.05), while the resistance rate to ceftriaxone (non-meningitis) continuously declined from 16.0% in 2014-2015 to 1.4% in 2018-2019 and 0% in 2020-2021 (Fisher = 24.463, P < 0.01). Conclusion: The common serotypes of S. pneumoniae isolated from children in Urumqi were types 19F, 19A, 23F, 6B, and 6A, which we found to have no marked change since the PCV13 introduction and the COVID-19 control However, the resistance rate to oral penicillin and ceftriaxone significantly declined in the COVID-19 control stage.

IGFBP3 epigenetic promotion induced by METTL3 boosts cardiac fibroblast activation and fibrosis.

Cardiac fibrosis remains an unresolved problem in heart disease. Its etiology is directly caused by the activation and proliferation of cardiac fibroblasts (CFs). However, there is limited information regarding the biological role of cardiac fibroblasts in cardiac fibrosis. Herein, we screened out a gene, IGFBP3, whose expression significantly increased in TGF-ß1-stimulated human primary CFs by mining RNA-Seq data for differential and WGCNA. We verified the IGFBP3's expression in transverse aortic constriction (TAC) surgery, isoproterenol (ISO)-induced cardiac fibrosis models, and TGFß1-stimulated mouse primary CFs. We also found that the knockdown of IGFBP3 could inhibit the migration and proliferation ability of CFs. Furthermore, we found that aberrant N6-methyladenosine(m6A) mRNA modifications in the animal model and activated CFs may regulate the expression of IGFBP3 in developing cardiac fibrosis. Silencing METTL3 could downregulate the expression of IGFBP3 and inhibit the activation of CFs and the degree of cardiac fibrosis both in vitro and in vivo. Indeed, we also verified the expression of METTL3 and IGFBP3 in the atrial tissues of patients with atrial fibrillation (AF). Thus, METTL3 may regulate IGFBP3's expression and CFs activation via RNA epigenetic modifications, laying the foundation for a specific and novel therapeutic target in cardiac fibrosis.

Epigenetic control of LncRNA NEAT1 enables cardiac fibroblast pyroptosis and cardiac fibrosis.

Cardiac fibroblasts (CFs) drive extracellular matrix remodeling after inflammatory injury, leading to cardiac fibrosis and diastolic dysfunction. Recent studies described the role of epigenetics in cardiac fibrosis. Nevertheless, detailed reports on epigenetics regulating CFs pyroptosis and describing their implication in cardiac fibrosis are still unclear. Here, we found that DNMT3A reduces the expression of lncRNA Neat1 and promotes the NLRP3 axis leading to CFs pyroptosis, using cultured cells, animal models, and clinical samples to shed light on the underlying mechanism. We report that pyroptosis-related genes are increased explicitly in cardiac fibrosis tissue and LPS-treated CFs, while lncRNA Neat1 decreased. Mechanistically, we show that loss of DNMT3A or overexpression of lncRNA Neat1 in CFs after LPS treatment significantly enhances CFs pyroptosis and the production of pyroptosis-related markers in vitro. It has been demonstrated that DNMT3A can decrease lncRNA Neat1, promoting NLRP3 axis activation in CFs treated with LPS. In sum, this study is the first to identify that DNMT3A methylation decreases the expression of lncRNA Neat1 and promotes CFs pyroptosis and cardiac fibrosis, suggesting that DNMT3A and NEAT1 may function as an anti-fibrotic therapy target in cardiac fibrosis.

Effects of miR-619-5p on proliferation, migration and invasion of human breast cancer cells / 中国药理学通报

Aim To investigate the involvement and mechanism of miR-619-5p in the proliferation, migration and invasion of human breast cancer cells. Methods The expression of miR-619-5p in breast cancer and normal breast tissue and cells was detected using bioinformatic analysis or qRT-PCR. After transfection with miR-619-5p mimics or inhibitors, the expression of miR-619-5p and EMT-related molecule mRNA was determined by qRT-PCR. Cell proliferation was detected using CCK-8 assay; cell migration and invasion capacity was estimated by the wound healing assay and Transwell assay. The protein levels of EMT-related molecules were analyzed by Western blot. The target genes of miR-619-5p were analyzed by bioinformatic a-nalysis, and a preliminary analysis of the potential target gene CREB1 was carried out. Results miR-619-5p was low expressed in breast cancer tissues and breast cancer cells. Compared with the control group, over-expression of miR-619-5p resulted in up-regula-tion of miR-619-5p expression levels and EMT epithelial markers, down-regulation of pro-EMT molecules and mesenchymal markers, impairment of cell proliferation, migration and invasion, and down-regulation of CREB1 expression. The results of the low miR-619-5p expression group were opposite to the above results. Conclusions In breast cancer tissue and cells, miR-619-5p expression is lower. miR-619-5p inhibits the proliferation, migration, invasion and EMT of breast cancer cells, and its possible mechanism of the effects may be targeting CREB1.

Recent research on the epidemiology and preventive strategies of neonatal group B Streptococcus infection in the latest decade / 中国当代儿科杂志

Currently, the main strategy for preventing neonatal group B Streptococcus (GBS) infection is prenatal screening combined with intrapartum antibiotic prophylaxis, which has effectively reduced the incidence of neonatal GBS early-onset disease. However, the burden of GBS infection is still significant. The intrapartum antibiotic prophylaxis strategy has limitations such as inducing antibiotic resistance and inability to effectively prevent GBS late-onset disease. It is crucial to develop and evaluate other prevention strategies, while paying close attention to assessing penicillin allergy in pregnant women and how to prevent GBS infection in neonates with negative maternal GBS screening. In recent years, there has been some progress in GBS vaccines and related immunological research, and the use of specific vaccines is expected to significantly reduce GBS infection in neonates.

Paying attention to the epidemic of group A Streptococcus infections in multiple European and American countries / 中国当代儿科杂志

At the end of 2022, the World Health Organization reported an increase in group A Streptococcus (GAS) infections, such as scarlet fever, in multiple countries. The outbreak primarily affected children under 10 years old, and the number of deaths was higher than anticipated, causing international concern. This paper reviews the current state of the GAS disease outbreak, its causes, and response measures. The authors aim to draw attention from clinical workers in China and increase their awareness and vigilance regarding this epidemic. Healthcare workers should be aware of the potential epidemiological changes in infectious diseases that may arise after the optimization of control measures for coronavirus disease 2019 to ensure children's health.

Effects of porcine urinary bladder matrix on motility and polarization of bone marrow-derived macrophages in mice / 中华烧伤杂志

Objective: To explore the effects of porcine urinary bladder matrix (UBM) on the motility and polarization of bone marrow-derived macrophages in mice, so as to provide evidence for the rational selection of stent in clinical wound repair. Methods: The method of experimental research was used. The microstructure of porcine UBM and absorbable dressing was observed under scanning electron microscope. Polyacrylamide gel electrophoresis was used to observe the protein distribution of the two stent extracts. The primary macrophages were induced from bone marrow-derived cells isolated from six 6-8-week-old male C57BL/6J mice (mouse age, sex, and strain, the same below) and identified. Three batches of macrophages were divided into porcine UBM extract group and absorbable dressing extract group. The cells in each group were cultured with Dulbecco's modified Eagle medium/F12 medium containing the corresponding extracts. The cell migration rate was detected and calculated on 1, 3, and 7 d after scratching by scratch test. The number of migrated cells at 12 and 24 h of culture was detected by Transwell experiment. The percentages of CD206 and CD86 positive cells at 24 h of culture was detected by flow cytometer. The numbers of sample in the above cell experiments were all 3. An incision was prepared on the left and right back of twelve mice, respectively. The left incision of each mouse was included in porcine UBM group and the right incision was included in absorbable dressing group, and the corresponding stents were implanted into the incisions respectively. On post operation day (POD) 7 and 14, the number of inflammatory cells infiltrated in the stent was detected by hematoxylin-eosin staining; the number of F4/80, transforming growth factor-β1 (TGF-β1), vascular endothelial growth factor (VEGF), and matrix metalloprotein-9 (MMP-9) positive cells and type Ⅰ collagen deposition in stents were observed by immunohistochemistry; the percentages of F4/80, CD86, and CD206 positive cells were observed by immunofluorescence staining. The numbers of sample in the above animal experiments were all 6. Data were statistically analyzed with analysis of variance for factorial design, analysis of variance for repeated measurement, and independent sample t test. Results: Porcine UBM has a dense basement membrane structure on one side and porous propria containing a fibrous structures on the other. Both sides of the absorbable dressing had three-dimensional porous structure. In the molecular weight range of (50-70)×103, multiple non-type Ⅰ collagen bands appeared in the lanes of porcine UBM extract, while no obvious bands appeared in the lanes of absorbable dressing extract. It had been identified that mouse bone marrow-derived cells had been successfully induced into macrophages. The cell migration rates in porcine UBM extract group were significantly higher than those in absorbable dressing extract group on 1, 3, and 7 d after scratching (with t values of 15.31, 19.76, and 20.58, respectively, P<0.05). The numbers of migrated cells in porcine UBM extract group were significantly more than those in absorbable dressing extract group at 12 and 24 h of culture (with t values of 12.20 and 33.26, respectively, P<0.05). At 24 h of culture, the percentage of CD86 positive cells in porcine UBM extract group ((1.27±0.19)%) was significantly lower than (7.34±0.14)% in absorbable dressing extract group (t=17.03, P<0.05);the percentage of CD206 positive cells in porcine UBM extract group was (73.4±0.7)%, significantly higher than (32.2±0.5)% in absorbable dressing extract group (t=119.10, P<0.05). On POD 7 and 14, the numbers of inflammatory cells infiltrated in the stents in porcine UBM group was significantly more than those in absorbable dressing group (with t values of 6.58 and 10.70, respectively, P<0.05). On POD 7 and 14, the numbers of F4/80, TGF-β1, VEGF, and MMP-9 positive cells in the stents in porcine UBM group were significantly more than those in absorbable dressing group (with t values of 46.11, 40.69, 13.90, 14.15, 19.79, 32.93, 12.16, and 13.21, respectively, P<0.05); type Ⅰ collagen deposition in the stents in porcine UBM group was more pronounced than that in absorbable dressing group; the percentages of CD206 positive cells in the stents in porcine UBM group were significantly higher than those in absorbable dressing group (with t values of 5.05 and 4.13, respectively, P<0.05), while the percentages of CD86 positive cells were significantly lower than those in absorbable dressing group (with t values of 20.90 and 19.64, respectively, P<0.05), and more M2-type macrophages were seen in the stents in porcine UBM group and more M1-type macrophages were seen in the stents in absorbable dressing group. Conclusions: Porcine UBM can enhance macrophage motility, induce M2 polarization and paracrine function, create a microenvironment containing growth factors such as TGF-β1 and MMP-9 tissue remodeling molecules, and promote tissue regeneration and extracellular matrix remodeling in mice.

Safety and efficacy analysis of hepatic artery infusion chemotherapy combined with immune targeted therapy for single CNLC Ⅰb hepatocellular carcinoma / 中华肝胆外科杂志

Objective:To investigate the safety and efficacy of FOLFOX (5-fluorouracil + calcium folinate + oxaliplatin) hepatic arterial infusion chemotherapy (FOLFOX-HAIC) combined with immune and targeted therapy as triple combination therapy for patients with single China Liver Cancer Staging (CNLC) Ⅰb hepatocellular carcinoma.Methods:A total of 20 patients with single CNLC Ⅰb hepatocellular carcinoma who received FOLFOX-HAIC combined with immune and targeted therapy as triple combination therapy in the First Affiliated Hospital of Guangxi Medical University from October 2021 to August 2022 were included. The clinical data of all patients was retrospectively analyzed. There were 18 males and 2 females, with the age of (55.1±9.9) years. Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and Modified Response Evaluation Criteria in Solid Tumors (mRECIST) were used to evaluate the efficacy of FOLFOX-HAIC combined with immune and targeted therapy, and the clinical safety of triple combination therapy was evaluated by common terminology criteria for adverse events 4.0.Results:According to RECIST 1.1, objective response rate of 20 patients was 70.0% (14/20) and disease control rate was 100.0% (20/20) after 2 cycles of treatment (one cycle of FOLFOX-HAIC plus programmed death-1 antibody). According to mRECIST, objective response rate was 90.0% (18/20) and the disease control rate was 100.0% (20/20) after 2 cycles of treatment. Following the treatment, 12 patients (60.0%) received liver tumor resection, and all of them achieved R 0 resection, 2 patients (10.0%) received radiotherapy, 3 patients (15.0%) stopped drug treatment for surgery, 2 patients (10.0%) refused surgery, and 1 patient (5.0%) died of multiple organ failure caused by immune hepatitis. According to pathological results, 3 patients (25.0%, 3/12) achieved pathological complete response, and 4 patients (33.3%, 4/12) achieved major pathological response. In the safety evaluation, the overall incidence of adverse events was 100.0% (20/20). Seven patients (35.0%) had grade 3 adverse events and 1 patient (5.0%) died of multiple organ failure due to immune hepatitis (grade 5). Grade 1-3 adverse events could be relieved after symptomatic treatment. Conclusion:The triple combination therapy of FOLFOX-HAIC combined with immune and targeted therapy is safe and has high objective response rate and disease control rate, which could be a new strategy for the neoadjuvant treatment of hepatocellular carcinoma.

[Interpretation of "Clinical Considerations for Monkeypox in Children and Adolescents" released by the US Centers for Disease Control and Prevention]. / ç¾Žå›½ç–¾ç— é¢„é˜²å’ŒæŽ§åˆ¶ä¸­å¿ƒå‘å¸ƒçš„ã€Šå„¿ç«¥å’Œé’å°‘å¹´çŒ´ç—˜çš„ä¸´åºŠæ³¨æ„äº‹é¡¹ã€‹è§£è¯».

In order to cope with monkeypox in children and adolescents, the US Centers for Disease Control and Prevention released "Clinical Considerations for Monkeypox in Children and Adolescents", which is specially written for pediatric health workers serving children and adolescents under the age of 18 years to standardize the clinical management of children and adolescents with exposure to monkeypox (human monkeypox or animal monkeypox) or with suspected or confirmed monkeypox. This document highlights the characteristics of children and adolescents and gives some valuable suggestions to the special issues in pediatric clinical practice, and it is worth studying by pediatric health workers who are preparing for a possible epidemic of monkeypox.

[Clinical features and epidemiological significance of pertussis in infants]. / å©´å„¿ç™¾æ—¥å’³çš„æµè¡Œç— å­¦æ„ä¹‰åŠå ¶ä¸´åºŠç‰¹ç‚¹.

Infantile pertussis is clear evidence for the persistent transmission of pertussis in communities. Infants are the most vulnerable population for pertussis infection and are also important nodes in pertussis transmission networks in communities, and therefore, the prevention of infantile pertussis is the core of prevention and control measures against pertussis including vaccine immunization. Although the cases of pertussis reported in China are mainly infants with pertussis, the actual number of infants with pertussis might be higher than the reported number. It is necessary in clinical practice to improve the awareness of this disease and promote related laboratory tests. On the basis of emphasizing the identification of pertussis in infants, timely diagnosis and treatment, follow-up visits, and standard management of the close contacts of infants with pertussis should be performed to reduce and block the community transmission of pertussis.

[Diagnosis and treatment of human monkeypox]. / 人感染猴痘的诊断和治疗.

The guideline for the diagnosis and treatment of monkeypox (2022 edition) issued by National Health Commission of the People's Republic of China introduces the key knowledge of the diagnosis and treatment of human monkeypox (HMPX) and does not systematically introduce the sampling methods and requirements of specimens for HMPX etiology testing and the discrepancy in diagnostic criteria between China and overseas. However, the doctors who are not engaged in dermatology lack understanding of the sampling methods and requirements of specimens for laboratory diagnosis of HMPX, and there are few relevant references available. This article collects the information on the diagnosis and treatment of HMPX, so as to provide a reference for learning, understanding, and application of this guideline.

Clinical characteristics and epidemiological significance of coronavirus disease 2019 in children and adolescents. / 儿童和青少年2019å† çŠ¶ç— æ¯’ç— çš„ä¸´åºŠè¡¨çŽ°åŠæµè¡Œç— å­¦æ„ä¹‰.

The epidemic of coronavirus disease 2019 (COVID-19) started in late December 2019, and spread rapidly throughout the world. In March 2020, the World Health Organization (WHO) declared global epidemic of COVID-19. According to the American Academy of Pediatrics, nearly 13 million children have been diagnosed with COVID-19 since the outbreak. In general, children and teens have milder symptoms and fewer deaths from COVID-19 than adults. Understanding the symptoms, infectivity, and transmission patterns of COVID-19 in children and adolescents is of great significance for timely identifying suspected patients and developing effective control measures. Considering that some children will not be vaccinated for quite some time in the future, it is more important to improve the understanding of the clinical and epidemiological significance of COVID-19 in children and adolescents. This article summarizes the current understanding of the clinical manifestations and epidemiological significance of COVID-19 in children and adolescents to provide a reference for clinical diagnosis and treatment and the formulation of epidemic prevention and control strategies in children's gathering institutions such as kindergartens and schools.