Objective:To provide clinical data for early identification and diagnosis of vascular embolism in children.Methods:We collected and analyzed the clinical data of children with vascular embolism diagnosed at the Children Medical Center of the First Affiliated Hospital of Hunan Normal University from January 2017 to January 2020.Results:A total of 29 children with vascular embolism were included.The male to female ratio was 2.2∶1(20/9); the age range was 1 month to 13 years, and the median age(IQR) was 16 (6-41)months.Among them, 22 cases were diagnosed with venous thrombosis, including 13 children with lower limb venous thrombosis(13/29, 44.8%), and six children with intracranial venous thrombosis(6/29, 20.7%). Arterial embolism was found in six cases, and left atrial appendage thrombosis was found in one case.Severe pneumonia was the most common primary disease(19/29, 65.5%), followed by cardiopulmonary resuscitation(3/29, 10.3%), and Kawasaki disease(3/29, 10.3%). Analysis on the risk factors of vascular embolization diseases, including catheter-related, long-term bed rest, elevated D-dimer, mechanical ventilation, and intravenous hormone administration, showed that 89.2%(25/29)had ≥3 risk factors at the same time, and 82.8%(24/29)had ≥5 risk factors at the same time.Conclusion:In children with vascular thrombotic diseases, deep venous thrombosis, especially lower extremity venous thrombosis, are common.The severe pneumonia is more common in primary disease.Children with multiple risk factors have a higher risk of developing vascular embolism.In clinic, coagulation function should be monitored and local symptoms should be observed for early identification.

Objective:To study the effect of alum on immune response in mice induced by HBoV1 VP2 VLPs.Methods:BABL/c mice were randomly divided into VLPs experimental group, alum adjuvant experimental group, PBS control group and alum adjuvant control group,the experimental group mice were intramuscular immunization with HBoV1 VP2 VLPs and HBoV1 VP2 VLPs added alum,control group mice were immunization with alum or PBS buffer,then to study the effect of alum on immune response in mice induced by HBoV1 VP2 VLPs by cellular and humoral immune strength.Results: Alum adjuvant decreased cellular immune response induced by HBoV1 VP2 VLPs(P<0.001),enhance the HBoV1 VP2 VLPs immuned serum IgG titer(P<0.05)and IgG activity(P<0.01).Conclusion:Alum adjuvant can enhance humoral immune response induced by HBoV1 VP2 VLPs,but weaken cellular immune response induced by HBoV1 VP2 VLPs,when HBoV1 VP2 VLPs used as a prophylactic vaccine it should add alum adjuvant,when used as a therapeutic vaccine,it should not add alum adjuvant.

Objective: To investigate the detection results and epidemiological characteristics of human adenovirus (HAdV) among children with community acquired pneumonia (CAP) in Hunan province. Methods: A descriptive retrospective survey was conducted to investigate the clinical epidemiological data of 33 056 children with CAP admitted to the Children′s Medical Center of Hunan People′s Hospital from May 1st, 2014 to April 30th, 2019.The seasonal distribution and demographic characteristics of HAdV infection were analyzed. Results: (1) A total of 33 056 children with CAP were included in this study.A total of 3 770 children with HAdV positive were detected, with a total detection rate of 11.40% (3 770/33 056). From May 2014 to April 2019, the detection rates of adenovirus in different years were 13.76%, 8.57%, 7.94%, 9.53%, 12.36% and 24.75% respectively.Adenovirus detection rate reached its peak in 2019.(2) The detection rate of HAdV among male children were higher than that among female children (χ²= 6.374, P=0.012). Among 3 770 children with HAdV infection, 3 036 (80.53%) were from 6 months to 5 years old.The detection rate of adenovirus were different in different age groups.The highest detection rate was 16.65% in 3 to 5 years old group (χ²=526.494, P<0.001). Among children with severe pneumonia, the detection rate of adenovirus was 18.43% (415/2 252). The detection rate of adenovirus was the highest in the age group of 6 months to 1 years, and the difference was statistically significant(χ²=71.485, P<0.001). (3) The detection rate of adenovirus was the lowest in autumn, and the other three seasons were all high- incidence seasons (χ²= 268.744, P<0.001). (4) The hospitalization days of adenovirus pneumonia were longer than those of non-adenovirus pneumonia (Z=-10.419, P<0.001). Conclusion The prevalence of HAdV infection is related to age, season and sex.The susceptibility of adenovirus varies with severity of pneumonia.We should be vigilant against the outbreak of adenovirus infection characterized by years.

Objective To investigate the detection results and epidemiological characteristics of hu﹣man adenovirus (HAdV) among children with community acquired pneumonia ( CAP) in Hunan province. Methods A descriptive retrospective survey was conducted to investigate the clinical epidemiological data of 33 056 children with CAP admitted to the Children′s Medical Center of Hunan People′s Hospital from May 1st,2014 to April 30th,2019. The seasonal distribution and demographic characteristics of HAdV infection were analyzed. Results (1) A total of 33 056 children with CAP were included in this study. A total of 3 770 children with HAdV positive were detected,with a total detection rate of 11. 40% (3 770/33 056). From May 2014 to April 2019,the detection rates of adenovirus in different years were 13. 76%,8. 57%, 7. 94%,9. 53%,12. 36% and 24. 75% respectively. Adenovirus detection rate reached its peak in 2019. (2) The detection rate of HAdV among male children were higher than that among female children (χ2 ＝ 6. 374, P＝0. 012). Among 3 770 children with HAdV infection,3 036 (80. 53%) were from 6 months to 5 years old. The detection rate of adenovirus were different in different age groups. The highest detection rate was 16. 65% in 3 to 5 years old group (χ2 ＝526. 494,P<0. 001). Among children with severe pneumonia,the detection rate of adenovirus was 18. 43% (415/2 252). The detection rate of adenovirus was the highest in the age group of 6 months to 1 years, and the difference was statistically significant ( χ2 ＝71. 485, P <0. 001). (3) The detection rate of adenovirus was the lowest in autumn,and the other three seasons were all high﹣incidence seasons (χ2 ＝ 268. 744,P<0. 001). (4) The hospitalization days of adenovirus pneumonia were longer than those of non﹣adenovirus pneumonia (Z＝ －10. 419,P<0. 001). Conclusion The preva﹣lence of HAdV infection is related to age,season and sex. The susceptibility of adenovirus varies with severity of pneumonia. We should be vigilant against the outbreak of adenovirus infection characterized by years.

Objective To analyze the clinical characteristics of fatal cases with confirmed severe ad﹣enovirus pneumonia in children in order to improve the diagnosis and treatment. Methods The fatal cases of severe adenovirus pneumonia admitted to Pediatric Intensive Care Unit of Hunan Provincial People′s Hospital from January 2019 to July 2019 were collected,whose clinical features,diagnosis,treatment,and the causes of death were analyzed retrospectively. Results A total of eight children were enrolled, and the age ranged from 3 months to 3 years old,and five cases were between 6 months to 2 years old. Three cases had underly﹣ing diseases. Adenovirus genotype identification was performed on six patients,and the results showed that all patients were infected with adenovirus type 7. All patients presented persistent high fever,with a peak temper﹣ature between 39. 8℃ to 41. 0℃,which persisted 10 to 37 days. Blood routine test before admission PICU showed that four cases had the decrease in white blood count and hemoglobin concentration,accompanied by﹣increased serum ferritin levels. Seven cases complicated with infection. Four cases had parainfluenza virus type 3 infection. Six cases had bacterial infection,and Gram﹣negative bacilli were predominant. One had fun﹣gal septicemia. Conventional mechanical ventilation were performed in all patients in this group. Four cases in this group died of severe acute respiratory distress syndrome. The other four cases died of disseminated intra﹣vascular coagulation associated with massive gastrointestinal bleeding, pulmonary hemorrhage, heart failure and septic shock combined with multiple organ failure. Conclusion Fatal adenoviruspneumonia mostly app﹣pears in children between 6 months to 2 years old or with underlying diseases. Adenovirus type 7 was the main serotype. The occurrence of reactive hemophagocytic phenomenon should be worsen progression of the disease. Co﹣infection may be an important cause of death.

Objective:To analyze the epidemiological characteristics of Mycoplasma pneumoniae ( Mp) infection in hospitalized children with community-acquired pneumonia in Hunan Province and to provide a theoretical basis for clinical diagnosis and treatment. Methods:The epidemiological characteristics of Mp infection in children hospitalized for community-acquired pneumonia in the Children′s Medical Center of the First Affiliated Hospital of Hunan Normal University (Hunan Provincial People′s Hospital) from January 1, 2013 to December 31, 2021 were retrospectively analyzed. Results:A total of 55 681 children with community-acquired pneumonia were enrolled during the study period, of whom 27.24% (15 170/55 681) were tested positive for Mp. The positive rate was lower in boys than in girls (23.39% vs 33.39%, χ 2=665.998, P<0.001). The positive rate of Mp infection increased with age with the highest rate in children who were 5-14 years old (67.92%) and the lowest in infants less than one year old (6.38%). The detection rates of Mp infection varied between years with the highest rate in 2019 (38.31%). The positive rates of Mp infection during the COVID-19 epidemic in 2020-2021 were similar to those in 2013-2018. Among the children hospitalized for community-acquired pneumonia, the detection rate of Mp was significantly higher in summer and autumn than in winter and spring (χ 2=648.753, P<0.001), with the highest detection rate reaching to 56.91% in the summer of 2019. In contrast, the detection rates of Mp in the spring and summer of 2020 were 15.60% and 17.44%, respectively, being the lowest detection rates ever for spring and summer, while the detection rates in the autumn and winter rebounded (31.22% and 28.48%). During the Mp epidemic in 2019, the age at onset, the proportion of severe pneumonia and the cost of treatment were higher as compared with those in other years. In 2020, the number of cases positive for Mp was the lowest on record, as was the proportion of severe pneumonia and admission rate to PICU ( P<0.001). Conclusions:In hospitalized children with community-acquired pneumonia, there were gender, age and season differences in Mp infection. In the summer of 2019, there was a Mp epidemic in Hunan Province, which increased the proportion of severe pneumonia and the cost of treatment. After the outbreak of COVID-19, the rate of Mp infection dropped significantly in the spring of in 2020 as well as in the summer, but rebounded in the autumn and winter. This might be due to the strict restrictive measures taken early during the COVID-19 pandemic that effectively controlled the spread of Mp.

Objective:To understand the prevalence of human parechovirus (HPeV) in neonates of Hunan Provincial People’s Hospital, and analyze genetic evolutionary characteristics.Methods:From June to September 2021, fecal samples of inpatient neonates were collected in Hunan Provincial People′s Hospital. TaqMan real-time qPCR and RT-PCR were used for HPeV screening and genotyping. High-throughput sequencing and PCR were used to obtain whole genomes. Phylogenetic analysis was performed after sequencing.Results:A total of 123 fecal samples of neonates were collected, of which 22 were HPeV positive, with 17.89% positive rate. All the strains belonged to the HPeV-1 genotype. One full-length genomic sequence of 7 269 bp were obtained, and provisionally named Hunan/HPeV/2021, which has the highest nucleotide identity with known HPeV-1 genotype, with 86.6%-91.9% nucleotide identity. The nucleotide and amino acid identity of open reading frame (ORF) with known similar sequences were 90.3%-92.6% and 97.3%-98.3%, respectively. The phylogenetic analysis showed that Hunan/HPeV/2021 belongs to the HPeV-1 genotype, which is clustered into the same clade as the popular HPeV-1 strains in China.Conclusions:HPeV has a high prevalence in inpatient neonates of Hunan Provincial People’s Hospital and belong to the HPeV-1 genotype.

As an important pathogen of community pneumonia in children，human adenovirus is one of the common pathogens of severe pneumonia.Its high mortality and sequelae have caused a great burden on children's families and society.The risk factors of severe adenoviral pneumonia include virus types，virus loads，age，immune status of patients，and environmental factors.Early diagnosis and comprehensive treatment help improve prognosis.The pathogenesis，risk factors，clinical manifestations，diagnosis and treatment，and prognosis of severe adenovirus pneumonia are reviewed in this paper.

Objective:To understand the epidemiological characteristics of human parainfluenza viruses（HPIVs）infections in patients with acute lower respiratory tract infection（ALRTI）in Changsha，Hunan from 2013 to 2023.Methods:The respiratory virus detection results,demographic characteristics and clinical data of children hospitalized with ALRTI in Children's Medical Center of Hunan Provincial People's Hospital (the First Affiliated Hospital of Hunan Normal University) from January 2013 to December 2023 were retrospectively collected.The epidemic characteristics and clinical symptoms of HPIVs infection were analyzed.Results:During the study,59 725 children with ALRTI were included,the detection rate of HPIVs was 6.66% (3 978/59 725),among which,HPIV1,HPIV2,HPIV3 were detected in 753(1.26%) cases,217(0.36%) cases and 3 055(5.12%) cases,respectively.Among 3 978 cases infected with HPIVs,the overall detection rate in males was higher than that in females(6.99% vs. 6.14%),and the detection rate of HPIVs in 6-11 months old was higher than those in other age groups,with statistically significant differences( P<0.001).Among cases infected with HPIVs,the main clinical diagnosis were mild pneumonia (77.28%) and acute bronchiolitis (14.40%).The detection rate of HPIV3 was the highest (84.62%) in 208 HPIVs-positive children with severe pneumonia,and the difference was statistically significant ( P<0.001).The detection rate of HPIVs varied across different years,reaching its peak in 2020 with a detection rate of 13.99% ( P<0.001).The overall epidemic peak of HPIVs was in spring and summer.The seasonal epidemic characteristics in different types of HPIVs were not completely consistent.The detection rates of HPIV1(2.07%) and HPIV2(0.60%) were the highest in autumn,while that of HPIV3 (7.11%) was the highest in spring ( P<0.001).The seasonal epidemic characteristics of HPIVs have changed in different years:From 2013 to 2019,HPIVs was mainly prevalent in spring and summer,then shifted to summer and autumn in 2020,and autumn as well as winter in 2021 to 2022,then resumed in spring and summer in 2023. Conclusion:From 2013 to 2023,HPIVs in Changsha,Hunan Province had unique epidemiological characteristics.HPIV3 is the dominant type of HPIVs infection in the hospitalized children with ALRTI in Changsha，Hunan.The epidemic peak of HPIVs was postponed in 2020 to 2022.Paying attention to the continuous monitoring of HPIVs infection is helpful to guide clinicians' diagnosis and treatment.

Objective:To summarize the clinical characteristics of children with Mycoplasma pneumoniae pneumonia(MPP) complicated with pleural effusion, and explore the effect of mixed adenovirus infection on children with MPP complicated with pleural effusion.Methods:The clinical data of children with MPP complicated with pleural effusion diagnosed in Children′s Medical Center at the First Affiliated Hospital of Hunan Normal University (Hunan Provincial People′s Hospital) from January 2013 to December 2019 were collected.MPP cases were divided into single infection group and mixed infection group according to whether mixing adenovirus infection.The clinical characteristics were compared between two groups.Results:A total of 180 children with MPP complicated with pleural effusion were included, the male to female ratio was 1.22∶1 (99/81), the age was 66.13 (44.35, 83.98) months, and the most common cases were children over 5 years old (55.56%). The length of hospitalization was 9.00 (7.00, 12.00) days.Fever (93.33%) and cough (98.33%) were the most common clinical manifestations, and mild increases in C-reactive protein, erythrocyte sedimentation rate and D-dimer were the most common laboratory results.Among included children, right pleural effusion was the most common (54.44%), bilateral pleural effusion accounted for 26.67%, and left pleural effusion accounted for 18.89%.Compared with single infection group, the mixed infection group had a longer hospital stay, a higher proportion of oxygen intake, a higher proportion of gamma globulin use, and a higher value of lactate dehydrogenase and aspartate aminotransferase.The results of multivariate Logistic regression analysis showed that compared with single infection group, although the mixed infection group had a higher proportion of gamma globulin use (36.54% vs.10.93%, P<0.05), the length of hospital stay, clinical manifestations, laboratory examination, chest CT and fiberoptic bronchoscopy showed no statistically significant difference between two groups. Conclusion:MPP complicated with pleural effusion is more common in children over 5 years old, especially in the right side.Mild increases of C-reactive protein, erythrocyte sedimentation rate, and D-dimer are more common.The clinical features of MPP complicated with pleural effusion are similar between mixed adenovirus infection group and single infection group.