Objective:This study aimed to introduce droplet digital PCR (ddPCR) for monitoring Epstein-Barr virus (EBV) infection after allogeneic hematopoietic stem cell transplantation (alloHSCT) in children and assess its viability as a complementary detection method in clinical settings.Methods:A total of 290 blood samples from 47 children undergoing alloHSCT were collected. Both ddPCR and real-time quantitative PCR (qPCR) were employed to detect EBV DNA load in plasma, with a comparison of detection efficiencies between the two methods. Continuous monitoring of 39 children was conducted to observe dynamic changes in EBV DNA load in plasma and analyze the merits and drawbacks of both methods.Results:The EBV positive detection rate of ddPCR was significantly higher than that of qPCR ( χ2=20.25, P<0.001), particularly in samples with low viral loads. Among the children monitored continuously for EBV DNA, 14 out of 39 exhibited positive ddPCR result. Notably, in two cases where patients displayed rash and fever symptoms with positive ddPCR result but negative qPCR result, ddPCR demonstrated heightened sensitivity in early EBV infection detection. Conclusions:ddPCR holds certain advantages in monitoring EBV infection post-alloHSCT in children, especially for samples with low viral loads. However, as this method is still in the exploratory stage of clinical application, further research and practice are needed to validate its utility.

Objective:This study aimed to provide basic data for the prevention, diagnosis and treatment of pediatric viral myocarditis (VMC) in China through analyzing the epidemic characteristics and disease burden of pediatric inpatients with VMC from 2016 to 2021.Methods:We performed a descriptive statistical analysis to the age, genders, seasons, regions and hospitalization cost and days of pediatric VMC inpatients and the death. All of the information was obtained from 27 Children′s hospitals or Maternal and Child Health hospitals of 23 provinces of China from 2016 to 2021.Results:A total of 7 647 599 cases including 1 646 VMC inpatients were admitted into our study. The annual numbers of hospitalizations were 173, 227, 313, 301, 295 and 337, with the hospitalized constituent ratios being 14.9/100 000, 17.9/100 000, 23.0/100 000, 20.5/100 000, 26.5/100 000 and 26.4/100 000 from 2016 to 2021. In recent 6 years, the proportion of VMC hospitalizations had increased yearly ( P<0.001), and had associated with the onset age ( P<0.001). Aged 12-≤18 years owned the highest hospitalized constituent ratio. The Northeast of China owned the largest number of VMC inpatients, and the East second to it. Among the 1 646 VMC children, there were 68 deaths, with the hospitalized case fatality rate of 4.13%. There were no significant differences between genders, age, seasons, years and fatality rate of VMC inpatients. For the diseases burden, the median of hospitalization days of all VMC inpatients was 10 days (IQR 6, 21), and the median of hospitalization cost was 1 1 842.3 RMB (IQR 6 969.22, 19 714.78). The median of hospitalization days of deceased VMC children was only 1 day (IQR 1, 3), the median cost could be 8 874.03 RMB (IQR 5 277.94, 5 6 151.59). Conclusions:In this study, we found that proportion of hospitalization of VMC children increased year by year, adolescence might be a risk factor of VMC. The fatality of VMC inpatients could be up to 4.13%, and the death led to a huge economic burden of society, family and individuals.

Objective:To investigate the etiological distribution of severe community-acquired pneumonia (CAP) in children in Hebei Province.Methods:The nasopharyngeal swab samples and clinical data from 314 children with severe pneumonia were retrospectively analyzed between January 2014 and January 2016.Results:Among the 314 children, 298 (94.94%) showed positive result for pathogens in their nasopharyngeal swab samples, with 246 cases (78.34%) of multiple pathogens, predominantly mixed viruses and bacteria (206 cases, 65.61%). A total of 848 strains of pathogens were detected, including 483 strains (56.96%) of viruses, predominantly respiratory syncytial virus with 97 strains of subtype A and 86 strains of B. Bacteria and atypical pathogens ( Mycoplasma pneumoniae) had 365 strains (43.04%), mainly Streptococcus pneumoniae (220 strains) and Haemophilus influenzae (119 strains). The detection rate of pathogens was higher in children under one year of age ( χ2=21.389, P<0.001). There were no significant differences in different seasons, but the detection rates of respiratory syncytial virus A, respiratory syncytial virus B, and Streptococcus pneumoniae were higher in autumn, winter, and spring, respectively, with statistically significant differences ( χ2=22.205, P<0.001; χ2=37.874, P<0.001; χ2=11.380, P=0.009). Conclusions:Nasopharyngeal swab sample testing in children with severe pneumonia typically shows a coexistence of viral and bacterial pathogens, with detection rates varying among different age groups and seasons. Nasopharyngeal swab sample testing for pathogens provides valuable references for the identification of clinical pathogens.

Respiratory syncytial virus (RSV) is an enveloped, negative-sense, single-stranded RNA virus of the Orthopneumovirus  genus of the Pneumoviridae family in the order Mononegavirales. RSV can cause acute upper and lower respiratory tract infections, sometimes with extrapulmonary complications. The disease burden of RSV infection is enormous, mainly affecting infants and older adults aged 75 years or above. Currently, treatment options for RSV are largely supportive. Prevention strategies remain a critical focus, with efforts centered on vaccine development and the use of prophylactic monoclonal antibodies. To date, three RSV vaccines have been approved for active immunization among individuals aged 60 years and above. For children who are not eligible for these vaccines, passive immunization is recommended. A newly approved prophylactic monoclonal antibody, Nirsevimab, which offers enhanced neutralizing activity and an extended half-life, provides exceptional protection for high-risk infants and young children. This review provides a comprehensive and detailed exploration of RSV's virology, immunology, pathogenesis, epidemiology, clinical manifestations, treatment options, and prevention strategies.
Humans ; Respiratory Syncytial Virus Infections/prevention & control* ; Respiratory Syncytial Viruses/pathogenicity* ; Respiratory Syncytial Virus, Human/pathogenicity* ; Antiviral Agents/therapeutic use*

China has classified the Corona Virus Disease 2019(COVID-19) as a statutory category B infectious disease and managed it according to Category B since January 8, 2023.In view that Omicron variant is currently the main epidemic strain in China, in order to guide the treatment of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) infection in children with the times, refer to the Diagnosis and Treatment Protocol for Novel Coronavirus Infection (Trial 10 th Edition), Expert Consensus on Diagnosis, Treatment and Prevention of Novel Coronavirus Infection in Children (Fourth Edition) and the Diagnosis and Treatment Strategy for Pediatric Related Viral Infections.The Expert Consensus on the Diagnosis, Treatment and Prevention of Novel Coronavirus Infection in Children (Fifth Edition) has been formulated and updated accordingly on related etiology, epidemiology, pathogenic mechanism, clinical manifestations, auxiliary examination, diagnosis and treatment, and added key points for the treatment of COVID-19 related encephalopathy, fulminating myocarditis and other serious complications for clinical reference.

Objective:To analyze the prevalence and burden of herpangina(HA)in Chinese children from 2016 to 2020, which provides basic data reference for the diagnosis, treatment and prevention and control of HA in China.Methods:The homepage information of hospitalized children with HA were collected from 27 children′s hospitals and maternal and child health hospitals in 23 provinces of China from 2016 to 2020 and the epidemiology, severity and disease burden of HA were descriptively and statistically analyzed.Results:A total of 24, 099 hospitalized children with HA were reported from 27 children′s hospitals and maternal and child health hospitals in 2016-2020. In all that the hospitalized children, the male-to-female ratio was 1.46∶1 and 23, 432 children (97.23%) were ≤ 6 years old. HA onset lasted from April to September and its peak was in June or July every year except 2020. The largest number of hospitalized children with HA were found in East China (8, 520/23, 849; 35.72%). During study years, the proportion of hospitalized children with HA among all admissions in 27 investigated hospitals was 0.42% (24, 099/5, 790, 910). In terms of regions, the highest proportion was in Northeast China 0.69% (1, 720/249, 244). A total of 1, 510 (6.27%) children were severe cases and the male-to-female ratio was about 1.35∶1; 1, 326 (87.81%) children were ≤ 3 years old and the highest proportion of severe cases was in 28 days to ≤ 1 years old children (7.47%, 784/10, 494). The median of expenses for hospitalized children with HA was 3, 570.41 RMB (IQR 2, 698.03-4, 747.30), and the median hospital stay was 5 days (IQR 4-6).Conclusions:HA onset in China was predominantly in summer and at the age of ≤ 6 years. Meanwhile, owing to a large number of hospitalized children with HA and the high expenditures they generated, HA caused a considerable disease burden.

Human parainfluenza viruses (HPIVs) are enveloped, single-stranded RNA viruses in the Paramyxoviridae family with four antigenically and genetically distinct types, HPIV1-4. HPIVs are important viral agents that cause acute respiratory infections in children and adults, and disease burden of HPIVs infection may be significantly underestimated. Currently, there are no effective vaccines and antivirals for prophylaxis and treatment of HPIVs infection. Attention needs to be paid to the pathogenic monitoring, pathogenesis, disease diagnosis and treatment, as well as the development of antiviral drugs and vaccines for HPIVs infection.

Objective:To investigate the epidemiological and clinical characteristics of human parainfluenza viruses (HPIVs) infection among hospitalized children with community-acquired pneumonia (CAP) in China, and provide basic data for diagnosis, treatment and prevention of HPIVs infection.Methods:From November 2014 to February 2020, 5 448 hospitalized children with CAP were enrolled in 14 hospitals in 11 provinces and municipalities directly under the Central Government in southern China and northern China. Nasopharyngeal aspirates or throat swabs were collected, and the nucleic acids of 18 types respiratory viruses including HPIV1-4 were screened by suspension array technology. Demographic data and clinical information were collected for statistical analysis.Results:The total detection rate of HPIVs in 5 448 children with CAP was 8.83% (481/5 448), and the detection rate in males was higher than that in females (62.79% vs. 37.21%; χ2=0.000, P=0.992). The detection rate of HPIVs in 1~< 3 years age group was higher than that in other age groups, and the difference was statistically significant ( χ2=61.893, P<0.001). The detection rate of HPIVs in the northern region was higher than that in the southern region (9.02% vs 8.65%), but the difference was not statistically significant ( χ2=0.239, P=0.625). The prevalence of HPIV1-4 in northern and southern China was not completely same. HPIV1 was mainly prevalent in autumn in both northern and southern regions. HPIV2 was prevalent in summer in northern China, and the detection rate was low in southern China. HPIV3 reached its peak in both spring and summer in both northern and southern China, but its duration was longer in southern China than in northern China. HPIV4 is mainly popular in autumn in both southern China and northern China. Among 481 children infected with HPIVs, 58.42% (281/481) were infected with HPIV alone, and the main clinical manifestations were cough (90.75%) and fever (68.68%). Out of the HPIV-positive cases, 42.62% (205/481) were co-infected with another type of HPIV or a different virus, while 11.43% (55/481) had co-infections with two or more different viruses. HPIV3 was the most common type of co-infection with other viruses. HPIV3 infection accounted for the largest proportion (76.80%) in 47 HPIVs-positive children with severe pneumonia. Conclusions:HPIVs is one of the most important pathogens causing CAP in children in China, and children under 3 years of age are the main populations of HPIVs infection. The prevalence characteristics of all types of HPIVs in children in the north and south are not completely same. HPIV3 is the dominant type of HPIV infections and causes more severe diseases.

Acute respiratory tract infection is the most common infectious disease in children, which seriously threatens children′s health.Rapid and accurate etiological diagnosis is of great significance for the clinical treatment and control of these diseases.Pathogen nucleic acid test was applied and became the main method of respiratory tract infection diagnosis for its high sensitivity and specificity.To regulate the application of pathogen nucleic acid amplification test in respiratory tract infection in children, improve the diagnosis level, expert consensus on nucleic acid amplification test of respiratory pathogens in children was prepared to guide the application and promote pathogens diagnosis ability.

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection (LRTI) and hospitalizations in infants under 1 year of age, seriously jeopardizing infants′ health.Most hospitalizations (up to 80%) due to RSV-LRTI occur in otherwise healthy infants born at term.At present, no effective treatment and preventative measure against RSV is available domestically.Passive immunization with fully human long-acting monoclonal antibody Nirsevimab offers immediate protection for all infants experiencing their first RSV season with one shot, thus ushering in a new era of prevention of RSV infection among infants.