Objective:To analyze the epidemiological features of respiratory syncytial virus (RSV) infection in Beijing, and monitor the sequence variations in RSV glycoprotein (G) gene and clinical features of infected children.Methods:Respiratory tract specimens were collected from children with acute respiratory infection in the Children′s Hospital Affiliated to Capital Institute of Pediatrics from January 1, 2023 to December 31, 2023. RSV-positive specimens screened by multiple nucleic acid testing were subjected to PCR to amplify the full-length RSV G gene. A phylogenetic tree was constructed after gene sequencing to analyze RSV subtypes and trace G gene variants. Clinical data were retrieved from the medical record system to analyze the clinical features of children with RSV infection in Beijing.Results:A total of 5 489 respiratory specimens were collected from 3 046 male patients and 2 443 female patients. The average age of the patients was 4.36 years. A total of 589 RSV-positive specimens (10.7%, 589/5 489) were detected with 349 from male patients and 240 from female patients. The average age of children with RSV infection was (2.51±2.78) years and the median age was 0.48 years. RSV had been circulating among children in Beijing since March 2023 with two epidemic peaks in May (24.6%, 122/496) and December (18.2%, 126/693). The predominant subtype of RSV in the first half of 2023 was subtype A, but it was replaced by subtype B from November 2023. Phylogenetic analysis revealed a novel G gene of RSV subtype B (RSV-B-BA9-954bp) with a length of 954 bp, which belonged to a new cluster in the phylogenetic tree. The percentage of patients admitted to the Intensive Care Unit (ICU) was higher in children with new variant of RSV subtype B infection than in those with common RSV subtype B infection [44.1% (15/34) vs 25.2% (31/123), χ 2=4.600, P=0.032], while the counts of white blood cells and the levels of C-reactive protein were lower in the children with new variant infection ( P<0.05). Conclusions:RSV has been prevalent among children in Beijing since March 2023 with two epidemic peaks. The predominant A subtype is gradually replaced by to B subtype. A new variant of RSV B G gene (RSV-B-BA9-954bp) is detected among the children.

Objective:To analyze the differentially expressed genes of human respiratory syncytial virus (RSV) subtype A genotype ON1, a predominant genotype in Beijing, after infecting A549 cells using transcriptomic sequencing, and provide potential targets for RSV prevention and treatment.Methods:A local strain (61397-ON1) identified by whole-genome sequencing as ON1 genotype of RSV subtype A was selected to infect A549 cells. Total mRNA was extracted, and the differentially expressed genes in infected and uninfected A549 cells were screened by transcriptomic sequencing. GO analysis and KEGG pathway analysis were performed. Besides, six genes with differential expression ratio greater than two times were randomly selected for qRT-PCR verification.Results:There were 1 632 differentially expressed genes between infected and uninfected A549 cells, of which 807 genes were up-regulated and 825 genes were down-regulated. The differentially expressed genes were mainly involved in immune response-related biological processes such as cytokine response and positive regulation of MAPK cascades, and were enriched in MAPK signaling pathway, NOD-like receptor signaling pathway, p53 signaling pathway, TNF signaling pathway, IL-17 signaling pathway and NF-κB signaling pathway. The results of qRT-PCR for six differentially expressed genes were consistent with the trend of transcriptome data.Conclusions:The differentially expressed genes of RSV A subtype ON1 genotype after infecting A549 cells are mainly involved in cytokine response and immune-related signaling pathways. This study provides basic data for further study of the molecular mechanism of RSV infection and the development of prevention and treatment strategies.

Objective:To explore the pathogenic agents of acute respiratory infection (ARI) in children in Beijing.Methods:In the cross-sectional study, 3 groups of children from different departments were enrolled from Feb 6 th, 2023 (6 th week) to May 28 th (21 th week), 2023, including influenza-like case group from emergency department for nucleic acid testing of influenza virus (Flu) and human metapneumovirus (HMPV), the outpatient ARI group under nucleic acid testing for Flu, respiratory syncytial virus (RSV), adenovirus (ADV), and parainfluenza virus (PIV), and the inpatient ARI group under nucleic acid testing for Flu, RSV, HMPV, ADV, human bocavirus (HBoV), Rhinovirus (Rh), PIV, coronavirus (HCoV), Mycoplasma pneumoniae (Mp) and Chlamydia pneumonia (Cp). Results:There were 320 influenza-like cases enrolled, including 192 males and 128 females, aged 4.7 (3.6, 6.9) years, and 117 cases (36.6%) positive for Flu A, which contained similar proportion of pandemic H1N1 (H1N1) 47.0% (55/117) and H3N2 53.0% (62/117), and 13 cases for HMPV 4.1% (13/320). The rate of Flu reached its peak at the 10 th week, with H1N1 as the predominant one from the 6 th to 9 th week (10.0%-50.0%) and then H3N2 from the 10 th to 16 th week (15.0%-90.0%). HMPV was detected from the 15 th week 5.0% (1/20), and then reached to 30.0% (6/20) at the 20 th week. In the outpatient ARI group, 7 573 were enrolled, including 4 131 males and 3 442 females, aged 4.0 (2.1, 5.3) years, and the highest positive rate for RSV 32.9% (2 491/7 573), followed by Flu A 12.1% (915/7 573). The dominant one was Flu A in weeks 6-14 (23.2%-74.7%), then RSV in the 15 th week 24.8% (36/145). In the inpatient ARI group, 1 391 patients were enrolled, including 804 males and 587 females, aged 3.3 (0.4, 5.8) years, and the highest positive rate for Rh 18.7% (260/1 391), followed by RSV 12.4% (173/1 391), Flu A 10.2% (142/1 391, of which 116 cases (81.7%) were H1N1, and 26 cases (18.3%) were H3N2) and HMPV 3.1% (43/1 391). H1N1 was detected from the 7 th week 10% (6/60), to peak in the 11 th week 31.8% (21/66). H3N2 was detected from the 8 th week 1.5% (1/68), and then kept in low level. The proportion of H1N1 among Flu was 81.7% (116/142) in the inpatient ARI group. RSV was detected from 12 th week 1.3% (1/80), reaching 30.4% (35/115) at 19 th week. The positive rate of HMPV reached 12.1% (14/116) at 21 th week. Conclusions:In the spring of 2023, the first one in Beijing is the Flu epidemic, with H1N1 being the predominant one in the early stage and H3N2 in the later stage. Then, there is a postponed RSV epidemic and an increased HMPV detection. In addition, nucleic acid testing for outpatient children should be strengthened to provide early warning of epidemics.

Objective:To summarize the clinical manifestations, diagnosis, treatment and prognosis of acute flaccid myelitis (AFM) in children.Methods:Clinical characteristics of 4 AFM cases from Department of Neurology, Children′s Hospital Affiliated to Capital Institute of Pediatrics, from September 2018 to November 2022, were analyzed retrospectively.Results:The age of 4 children with AFM was 7 years, 4 years and 3 months, 7 years and 1 month, 6 years and 5 months, respectively. There were 2 boys and 2 girls. Prodromal infection status showed 3 children of respiratory tract infection and 1 child of digestive tract infection. The main manifestation was asymmetrical limb weakness after infection, and the affected limb range was from monoplegia to quadriplegia. Cranial nerve injury was involved in 1 child, no encephalopathy. Magnetic resonance imaging in the spinal cord of all 4 children showed long T1 and T2 signals, mainly involving gray matter. Cerebrospinal fluid cell-protein separation was observed in 2 children. Pathogen detected in 1 child pharyngeal swab was enterovirus D68. Antibody IgM to adenovirus was positive in the blood of 1 child. Antibody IgG against Echo and Coxsackie B virus were positive in the blood of another child. After glucocorticoid, human immunoglobulin or simple symptomatic treatment and at the same time under later rehabilitation training, muscle strength recovered to different degrees, but there were disabilities left in 3 children.Conclusions:AFM should be considered in children with acute and asymmetrical flaccid paralysis accompanied by abnormal magnetic resonance imaging signal in the central region of spinal cord, especially post-infection. The effective treatment is limited and the prognosis is poor.

Objective:To explore the latent classes of parental feeding behaviors in preschool children, and to examine the relationship between potential types of parental feeding behaviors and parental depression status.Methods:From May to July 2021, parents of preschoolers from eight kindergartens in Shanghai were recruited and investigated.A paper-based questionnaire consisting of the Chinese preschooler’s caregivers’ feeding behavior scale (CPCFBS) and the center for epidemiological studies depression scale (CESD-10) was employed.Finally, a total of 1 006 valid questionnaires were retrieved.Mplus 8.0 and SPSS 26.0 were used for statistical analysis.The latent class analysis was used to identify subgroups of parents based on their feeding practices.Multinomial Logistic regression was used to examine the relevant influencing factors.Results:The feeding behaviors of parental of preschool children could be divided into four potential categories: " high responsiveness and high non-responsiveness type" (24.55%), " low responsiveness and high non-responsiveness type" (27.44%), " high responsiveness and low non-responsiveness type" (28.33%) and " low responsiveness and low non-responsiveness type" (19.68%). The parents with depression status were less likely to be categorized as " high responsiveness and low non-responsiveness type" ( OR=0.386, 95% CI: 0.218-0.684). The parents with older children were more likely to be categorized as " low responsiveness and low non-responsiveness type" ( OR=1.318, 95% CI: 1.039-1.672). Conclusion:The feeding practices of parents of preschool children can be categorized into four latent classes.The parents with depression status are more likely to adopt non-responsive feeding practice than responsive feeding practice.Actively paying attention to and improving the depression status of parents may help the feeder to adopt scientific feeding behavior.

Objective: To investigate the cause of an incident of occupational contact dermatitis in a farm in Tianjin Prefecture, so as to provide insights into occupational safety. Methods: The disinfection process, use of disinfectants and individual protective measures in this farm were collected, and a field epidemiological investigation was conducted to collect the demographic characteristics, history of occupational contact, clinical symptoms, diagnosis and treatment data, and onset of disease among individuals with the same type of job. The cause of this incident was analyzed. Results: There were ten interns exposed to potassium hydrogen sulfate compounds simultaneously in this farm, and then, nine interns developed skin flushing across the body, and swelling and itching of the skin. Among these ten interns, five individuals were admitted to hospitals because of severe symptoms and were then clinically diagnosed as systemic contact dermatitis. All five individuals were cured following treatments. Epidemiological survey showed that all cases had a definite history of occupational contact with potassium hydrogen sulfate compounds but without use of any protective agents. In addition, there were thirty-five individuals with the same type of job in this farm that developed similar symptoms when they joined in the disinfection for the first time, and these individuals were self-cured following cessation to contact; however, recurrence of symptoms was found following contacts again. Conclusion This is a cluster of occupational contact dermatitis caused by exposure to potassium hydrogen sulfate compound.

Objective:To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China.Methods:The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ 2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M ( Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China ( P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion:HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.

Objective:To understand the common viral infection among the surveillance cases of fever respiratory syndrome (FRS) in nine provinces in China.Methods:The research data were obtained from nine provinces (Anhui, Beijing, Guangdong, Hebei, Hunan, Jilin, Shandong, Shaanxi and Xinjiang) in the "Infectious Disease Surveillance Technology Platform Information Management System" of the Chinese Center for Disease Control and Prevention from January 2009 to June 2021. Finally, 8 243 FRS cases with nucleic acid detection results of eight viruses [human influenza virus (HIFV), human respiratory syncytial virus (HRSV), human adenovirus (HAdV), human parainfluenza virus (HPIV), human rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV) and human Boca virus (HBoV)] were included in the study. The χ 2 test/Fisher exact probability method was used to analyze the difference of virus detection rate in different age groups, regions and seasons. Results The M ( Q1, Q3) age of 8 243 FRS cases was 4 (1, 18) years old, and 56.56% (4 662 cases) were children under 5 years old. Males accounted for 58.1% (4 792 cases) of all cases. All cases were from outpatient/emergency department (2 043 cases) and inpatient department (6 200 cases). The virus detection rates of FRS cases from high to low were HRSV, HIFV, HPIV, HRV, HAdV, HMPV, HCoV and HBoV. Two or more viruses were detected simultaneously in 524 cases, accounting for 15.66% of virus-positive cases. The difference of the virus detection rate in different age groups was statistically significant (all P values<0.05), and the virus detection rate in children<5 years old was higher (49.96%). The positive rate of any virus in south China was higher than that in north China ( P<0.001). The virus-positive FRS cases were detected throughout the year. The detection rate of HRSV was higher in autumn and winter. The detection rate of HIFV was higher in winter. The detection rate of HMPV was higher in winter and spring. The detection rates of HPIV, HRV, HCoV and HBoV were higher in summer and autumn, while there was no significant difference in the detection rate of HAdV in different seasons. Compared with 2009-2019, the detection rate of any virus in 2020-2021 decreased from 41.37% to 37.86%. The detection rate of HIFV decreased sharply from 10.62% to 1.37%. The detection rate of HPIV decreased from 8.24% to 5.88%. The detection rate of HRV and HBoV increased from 5.43% and 1.79% to 9.67% and 3.19%, respectively. Conclusion:HRSV and HIFV infections are more common among FRS cases in nine provinces in China from 2009 to 2021, and the epidemiological characteristics of eight common respiratory viruses vary in different age groups, regions and seasons.

Objective:To clarify the infection and epidemic characteristics of the human metapneumovirus (HMPV) in Chinese patients with febrile respiratory syndrome (FRS), and to provide important baseline data for clinical diagnosis, treatment, prevention and control of HMPV-induced respiratory tract diseases in China.Methods:FRS cases from January 2009 to June 2021 in 9 provinces in China, including Beijing, Hebei, Jilin, Shandong, Shaanxi, Xinjiang, Anhui, Guangdong, Hunan were retrospectively analyzed for their respiratory samples, clinical and epidemic data.The respiratory samples were detected for HMPV by quantitative real-time PCR.Results:A total of 11 660 cases were tested for HMPV, involving 296 (2.54%) HMPV-positive cases.Among 296 HMPV-positive cases, 218 were single HMPV infection, and 78/296 (26.35%) were co-infected with one or more respiratory viruses.HMPV mainly affected children under 5 years of age (3.10%), and in this population, the proportion of pneumonia in HMPV co-infection cases was significantly higher than that of single HMPV infection.HMPV could be detected all year round, which was more popular in winter and spring, with the peak of HMPV epidemic in March.Conclusions:HMPV is one of the important pathogens causing acute respiratory infection in children, showing a clear seasonal epidemic.HMPV can be infected alone or in combination with other respiratory viruses, which may increase the risk of pneumonia in children.

Objective:To investigate the prevalence and genetic characteristics of human adenovirus (HAdV) in healthy children and diarrheal children in Beijing.Methods:A total of 1 834 fecal samples were collected from diarrheal children younger than 6 years old in outpatients from January, 2015 to December, 2017 and from healthy children with the same age group from May, 2016 to February, 2017. The hexon and fiber genes of HAdV were detected for genotyping and the sequences analysis, respectively.Results:The detection rate of HAdVs in healthy children (1.5%, 8/536) was significantly lower than that in children with diarrhea (7.4%, 96/1 298) ( χ2=23.62, P<0.001). HAdV-41 was the dominant type detected both in the healthy children and diarrheal outpatients. There was no gender difference in HAdV-positive children with diarrhea. Except for newborns with no positive case, there was no difference in the detection rate of HAdV among the other age groups. There was no obvious seasonality of HAdV prevalence. Phylogenetic analysis showed that HAdV-41 strains circulating in Beijing belonged to three evolutionary branches, and strains with 15-amino acid truncated in the shaft of fiber were found. Conclusions:HAdV was one of the important pathogens causing diarrhea in children in Beijing from 2015 to 2017, with HAdV-41 as the predominant type.