ObjectiveTo analyze the infection characteristics of human respiratory syncytial virus (HRSV) among children hospitalized with acute lower respiratory tract infection (ALRTI) in a specialized pediatric hospital in Shanghai, so as to provide evidence-based support for optimizing the prevention and control strategies and clinical diagnosis and treatment of respiratory tract infections in children in this region. MethodsA retrospective analysis was performed to the clinical and etiological data of 29 260 children hospitalized for ALRTI in Shanghai Children’s Hospital from January 2021 to December 2024. HRSV and 12 other common respiratory pathogens were detected with multiplex polymerase chain reaction (PCR) and capillary electrophoresis. Demographic and clinical data were collected for statistical analyses. A total of2 412 cases with positive HRSV were divided into the severe group and the non-severe group. Clinical characteristics between the two groups were compared using the Mann-Whitney U test and the chi- square (χ²) test. Additionally, the related influencing factors of severe HRSV infection were explored. ResultsThe overall positivity rate of HRSV from 2021 to 2024 was 8.24% (2 412/29 260), with statistically significant differences observed across the four years (χ²=389.42, P<0.001). The highest positivity rate was in 2021 (14.76%), with a high prevalence throughout the year. In 2022, when non-pharmaceutical interventions (NPIs) were implemented, the HRSV positivity rate was the lowest (4.93%), with a winter-dominant epidemic pattern. In 2023, after the NPIs were lifted, the HRSV positivity rate showed a slight rebound (8.14%), presenting a double-peak pattern. In 2024, the HRSV positivity rate slightly decreased compared to that in 2023 (6.29%), exhibiting a winter and spring-dominant epidemic pattern. Among the hospitalized children with ALRTI, the HRSV positivity rate in males (8.85%) was higher than that in females (7.51%), and the difference was statistically significant (χ²=17.33, P<0.001). Age distribution showed that 82.26% (1 984/2 412) of HRSV infections occurred in children aged 3 years old and below. Besides, as age increased, the infection rate of HRSV showed a gradually decreasing trend (P<0.001). Among the 2 412 children with HRSV infection, the proportion of severe cases was 22.31% (538/2 412), while the non-severe cases accounted for 77.69% (1 874/2 412). Compared with non-severe cases, severe cases were more frequently presented with high fever, longer duration of wheezing, as well as higher rates of underlying diseases or co-infection with Mycoplasma pneumoniae (P<0.001). ConclusionThe prevalence intensity of HRSV varied yearly from 2021 to 2024. After the removal of NPIs in 2023, a slight rebound with a double-peak epidemic pattern was observed. HRSV remained a common pathogen in children hospitalized for ARLTI, and children aged 3 years old and below constituted the highest proportion for infection. Compared with non-severe cases, those with severe HRSV infections were more prone to presenting with high fever and a longer duration of wheezing. Children with positive HRSV who had underlying diseases or co-infection with Mycoplasma pneumonia were more likely to develop severe conditions.

Objective:To explore the clinical characteristics and prognostic risk factors of accidental injuries in pediatric intensive care unit(PICU).Methods:The children with accidental injuries admitted to the PICU at Shanghai Children′s Hospital from January 2017 to December 2019 were analyzed retrospectively.The patients were divided into survival group and death group according to outcome.We collected the patients′ clinical data and laboratory indexes, and analyzed the differences between two groups.Multivariate Logistic regression was used to screen the risk factors of death and receiver-operating characteristic(ROC)curve was used to determine the threshold.Results:(1)A total of 253 children were included, accounting for 5.2% of PICU hospitalization during the same period.There were 137 males(54.2%)and 116 females(45.8%), with an average age of 45(19, 96)months.The top three causes of accidental injuries were fall injury in 82 cases(32.4%), traffic accident in 70 cases(27.7%)and foreign body in 39 cases(15.4%). There were 22 cases of deaths, with a fatality rate of 8.7%.(2)The mean arterial pressure at admission in the death group was lower than that in the survival group( P<0.05), and the total length of stay was longer( P<0.001). There were significant differences in Glasgow coma scale, Pediatric Risk of Mortality Scoring Ⅲ(PRISM Ⅲ)between the two groups( P<0.001). In the death group, and the blood lactic acid(LA) significantly increased( P<0.001), hemoglobin and fibrinogen were lower than those in the survival group, the activated partial thromboplastin time and prothrombin time(PT)were significantly prolonged( P<0.001). (3)Multivariate Logistic regression analysis showed that PRISM Ⅲ score, LA and PT were independent risk factors for the death of accidental injuries.The area under curve(AUC)of PRISM Ⅲ score was 0.987(95% CI 0.976-0.999, P<0.001)and the cut-off value was 11 with a sensitivity of 100% and a specificity of 95.7%.The AUC of LA was 0.886(95% CI 0.810-0.961, P<0.001)and the cut-off value was 3.1 mmol/L with a sensitivity of 85.7% and a specificity of 77.3%.The AUC of PT was 0.835(95% CI 0.730-0.941, P<0.001)and the cut-off value was 13.9 s with a sensitivity of 86.6% and a specificity of 72.7%. Conclusion:The main accidental injuries in PICU of our hospital in the past three years are falling injuries, traffic accidents and foreign body injuries.PRISM Ⅲ score, LA and PT at admission are independent risk factors for predicting death.